Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1 | /* |
Ingo Molnar | 57c0c15 | 2009-09-21 12:20:38 +0200 | [diff] [blame] | 2 | * Performance events core code: |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3 | * |
| 4 | * Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de> |
| 5 | * Copyright (C) 2008-2009 Red Hat, Inc., Ingo Molnar |
| 6 | * Copyright (C) 2008-2009 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com> |
| 7 | * Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com> |
| 8 | * |
Ingo Molnar | 57c0c15 | 2009-09-21 12:20:38 +0200 | [diff] [blame] | 9 | * For licensing details see kernel-base/COPYING |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 10 | */ |
| 11 | |
| 12 | #include <linux/fs.h> |
| 13 | #include <linux/mm.h> |
| 14 | #include <linux/cpu.h> |
| 15 | #include <linux/smp.h> |
| 16 | #include <linux/file.h> |
| 17 | #include <linux/poll.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 18 | #include <linux/slab.h> |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 19 | #include <linux/hash.h> |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 20 | #include <linux/sysfs.h> |
| 21 | #include <linux/dcache.h> |
| 22 | #include <linux/percpu.h> |
| 23 | #include <linux/ptrace.h> |
| 24 | #include <linux/vmstat.h> |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 25 | #include <linux/vmalloc.h> |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 26 | #include <linux/hardirq.h> |
| 27 | #include <linux/rculist.h> |
| 28 | #include <linux/uaccess.h> |
| 29 | #include <linux/syscalls.h> |
| 30 | #include <linux/anon_inodes.h> |
| 31 | #include <linux/kernel_stat.h> |
| 32 | #include <linux/perf_event.h> |
Li Zefan | 6fb2915 | 2009-10-15 11:21:42 +0800 | [diff] [blame] | 33 | #include <linux/ftrace_event.h> |
Jason Wessel | 3c502e7 | 2010-11-04 17:33:01 -0500 | [diff] [blame] | 34 | #include <linux/hw_breakpoint.h> |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 35 | |
| 36 | #include <asm/irq_regs.h> |
| 37 | |
Peter Zijlstra | 82cd6de | 2010-10-14 17:57:23 +0200 | [diff] [blame] | 38 | atomic_t perf_task_events __read_mostly; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 39 | static atomic_t nr_mmap_events __read_mostly; |
| 40 | static atomic_t nr_comm_events __read_mostly; |
| 41 | static atomic_t nr_task_events __read_mostly; |
| 42 | |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 43 | static LIST_HEAD(pmus); |
| 44 | static DEFINE_MUTEX(pmus_lock); |
| 45 | static struct srcu_struct pmus_srcu; |
| 46 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 47 | /* |
| 48 | * perf event paranoia level: |
| 49 | * -1 - not paranoid at all |
| 50 | * 0 - disallow raw tracepoint access for unpriv |
| 51 | * 1 - disallow cpu events for unpriv |
| 52 | * 2 - disallow kernel profiling for unpriv |
| 53 | */ |
| 54 | int sysctl_perf_event_paranoid __read_mostly = 1; |
| 55 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 56 | int sysctl_perf_event_mlock __read_mostly = 512; /* 'free' kb per user */ |
| 57 | |
| 58 | /* |
| 59 | * max perf event sample rate |
| 60 | */ |
| 61 | int sysctl_perf_event_sample_rate __read_mostly = 100000; |
| 62 | |
| 63 | static atomic64_t perf_event_id; |
| 64 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 65 | void __weak perf_event_print_debug(void) { } |
| 66 | |
Matt Fleming | 84c7991 | 2010-10-03 21:41:13 +0100 | [diff] [blame] | 67 | extern __weak const char *perf_pmu_name(void) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 68 | { |
Matt Fleming | 84c7991 | 2010-10-03 21:41:13 +0100 | [diff] [blame] | 69 | return "pmu"; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 70 | } |
| 71 | |
Peter Zijlstra | 33696fc | 2010-06-14 08:49:00 +0200 | [diff] [blame] | 72 | void perf_pmu_disable(struct pmu *pmu) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 73 | { |
Peter Zijlstra | 33696fc | 2010-06-14 08:49:00 +0200 | [diff] [blame] | 74 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
| 75 | if (!(*count)++) |
| 76 | pmu->pmu_disable(pmu); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 77 | } |
| 78 | |
Peter Zijlstra | 33696fc | 2010-06-14 08:49:00 +0200 | [diff] [blame] | 79 | void perf_pmu_enable(struct pmu *pmu) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 80 | { |
Peter Zijlstra | 33696fc | 2010-06-14 08:49:00 +0200 | [diff] [blame] | 81 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
| 82 | if (!--(*count)) |
| 83 | pmu->pmu_enable(pmu); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 84 | } |
| 85 | |
Peter Zijlstra | e9d2b06 | 2010-09-17 11:28:50 +0200 | [diff] [blame] | 86 | static DEFINE_PER_CPU(struct list_head, rotation_list); |
| 87 | |
| 88 | /* |
| 89 | * perf_pmu_rotate_start() and perf_rotate_context() are fully serialized |
| 90 | * because they're strictly cpu affine and rotate_start is called with IRQs |
| 91 | * disabled, while rotate_context is called from IRQ context. |
| 92 | */ |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 93 | static void perf_pmu_rotate_start(struct pmu *pmu) |
Peter Zijlstra | b5ab4cd | 2010-09-06 16:32:21 +0200 | [diff] [blame] | 94 | { |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 95 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
Peter Zijlstra | e9d2b06 | 2010-09-17 11:28:50 +0200 | [diff] [blame] | 96 | struct list_head *head = &__get_cpu_var(rotation_list); |
Peter Zijlstra | b5ab4cd | 2010-09-06 16:32:21 +0200 | [diff] [blame] | 97 | |
Peter Zijlstra | e9d2b06 | 2010-09-17 11:28:50 +0200 | [diff] [blame] | 98 | WARN_ON(!irqs_disabled()); |
Peter Zijlstra | b5ab4cd | 2010-09-06 16:32:21 +0200 | [diff] [blame] | 99 | |
Peter Zijlstra | e9d2b06 | 2010-09-17 11:28:50 +0200 | [diff] [blame] | 100 | if (list_empty(&cpuctx->rotation_list)) |
| 101 | list_add(&cpuctx->rotation_list, head); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 102 | } |
| 103 | |
| 104 | static void get_ctx(struct perf_event_context *ctx) |
| 105 | { |
| 106 | WARN_ON(!atomic_inc_not_zero(&ctx->refcount)); |
| 107 | } |
| 108 | |
| 109 | static void free_ctx(struct rcu_head *head) |
| 110 | { |
| 111 | struct perf_event_context *ctx; |
| 112 | |
| 113 | ctx = container_of(head, struct perf_event_context, rcu_head); |
| 114 | kfree(ctx); |
| 115 | } |
| 116 | |
| 117 | static void put_ctx(struct perf_event_context *ctx) |
| 118 | { |
| 119 | if (atomic_dec_and_test(&ctx->refcount)) { |
| 120 | if (ctx->parent_ctx) |
| 121 | put_ctx(ctx->parent_ctx); |
| 122 | if (ctx->task) |
| 123 | put_task_struct(ctx->task); |
| 124 | call_rcu(&ctx->rcu_head, free_ctx); |
| 125 | } |
| 126 | } |
| 127 | |
| 128 | static void unclone_ctx(struct perf_event_context *ctx) |
| 129 | { |
| 130 | if (ctx->parent_ctx) { |
| 131 | put_ctx(ctx->parent_ctx); |
| 132 | ctx->parent_ctx = NULL; |
| 133 | } |
| 134 | } |
| 135 | |
Arnaldo Carvalho de Melo | 6844c09 | 2010-12-03 16:36:35 -0200 | [diff] [blame^] | 136 | static u32 perf_event_pid(struct perf_event *event, struct task_struct *p) |
| 137 | { |
| 138 | /* |
| 139 | * only top level events have the pid namespace they were created in |
| 140 | */ |
| 141 | if (event->parent) |
| 142 | event = event->parent; |
| 143 | |
| 144 | return task_tgid_nr_ns(p, event->ns); |
| 145 | } |
| 146 | |
| 147 | static u32 perf_event_tid(struct perf_event *event, struct task_struct *p) |
| 148 | { |
| 149 | /* |
| 150 | * only top level events have the pid namespace they were created in |
| 151 | */ |
| 152 | if (event->parent) |
| 153 | event = event->parent; |
| 154 | |
| 155 | return task_pid_nr_ns(p, event->ns); |
| 156 | } |
| 157 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 158 | /* |
| 159 | * If we inherit events we want to return the parent event id |
| 160 | * to userspace. |
| 161 | */ |
| 162 | static u64 primary_event_id(struct perf_event *event) |
| 163 | { |
| 164 | u64 id = event->id; |
| 165 | |
| 166 | if (event->parent) |
| 167 | id = event->parent->id; |
| 168 | |
| 169 | return id; |
| 170 | } |
| 171 | |
| 172 | /* |
| 173 | * Get the perf_event_context for a task and lock it. |
| 174 | * This has to cope with with the fact that until it is locked, |
| 175 | * the context could get moved to another task. |
| 176 | */ |
| 177 | static struct perf_event_context * |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 178 | perf_lock_task_context(struct task_struct *task, int ctxn, unsigned long *flags) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 179 | { |
| 180 | struct perf_event_context *ctx; |
| 181 | |
| 182 | rcu_read_lock(); |
Peter Zijlstra | 9ed6060 | 2010-06-11 17:36:35 +0200 | [diff] [blame] | 183 | retry: |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 184 | ctx = rcu_dereference(task->perf_event_ctxp[ctxn]); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 185 | if (ctx) { |
| 186 | /* |
| 187 | * If this context is a clone of another, it might |
| 188 | * get swapped for another underneath us by |
| 189 | * perf_event_task_sched_out, though the |
| 190 | * rcu_read_lock() protects us from any context |
| 191 | * getting freed. Lock the context and check if it |
| 192 | * got swapped before we could get the lock, and retry |
| 193 | * if so. If we locked the right context, then it |
| 194 | * can't get swapped on us any more. |
| 195 | */ |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 196 | raw_spin_lock_irqsave(&ctx->lock, *flags); |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 197 | if (ctx != rcu_dereference(task->perf_event_ctxp[ctxn])) { |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 198 | raw_spin_unlock_irqrestore(&ctx->lock, *flags); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 199 | goto retry; |
| 200 | } |
| 201 | |
| 202 | if (!atomic_inc_not_zero(&ctx->refcount)) { |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 203 | raw_spin_unlock_irqrestore(&ctx->lock, *flags); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 204 | ctx = NULL; |
| 205 | } |
| 206 | } |
| 207 | rcu_read_unlock(); |
| 208 | return ctx; |
| 209 | } |
| 210 | |
| 211 | /* |
| 212 | * Get the context for a task and increment its pin_count so it |
| 213 | * can't get swapped to another task. This also increments its |
| 214 | * reference count so that the context can't get freed. |
| 215 | */ |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 216 | static struct perf_event_context * |
| 217 | perf_pin_task_context(struct task_struct *task, int ctxn) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 218 | { |
| 219 | struct perf_event_context *ctx; |
| 220 | unsigned long flags; |
| 221 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 222 | ctx = perf_lock_task_context(task, ctxn, &flags); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 223 | if (ctx) { |
| 224 | ++ctx->pin_count; |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 225 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 226 | } |
| 227 | return ctx; |
| 228 | } |
| 229 | |
| 230 | static void perf_unpin_context(struct perf_event_context *ctx) |
| 231 | { |
| 232 | unsigned long flags; |
| 233 | |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 234 | raw_spin_lock_irqsave(&ctx->lock, flags); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 235 | --ctx->pin_count; |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 236 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 237 | put_ctx(ctx); |
| 238 | } |
| 239 | |
Peter Zijlstra | f67218c | 2009-11-23 11:37:27 +0100 | [diff] [blame] | 240 | static inline u64 perf_clock(void) |
| 241 | { |
Peter Zijlstra | c676329 | 2010-05-25 10:48:51 +0200 | [diff] [blame] | 242 | return local_clock(); |
Peter Zijlstra | f67218c | 2009-11-23 11:37:27 +0100 | [diff] [blame] | 243 | } |
| 244 | |
| 245 | /* |
| 246 | * Update the record of the current time in a context. |
| 247 | */ |
| 248 | static void update_context_time(struct perf_event_context *ctx) |
| 249 | { |
| 250 | u64 now = perf_clock(); |
| 251 | |
| 252 | ctx->time += now - ctx->timestamp; |
| 253 | ctx->timestamp = now; |
| 254 | } |
| 255 | |
| 256 | /* |
| 257 | * Update the total_time_enabled and total_time_running fields for a event. |
| 258 | */ |
| 259 | static void update_event_times(struct perf_event *event) |
| 260 | { |
| 261 | struct perf_event_context *ctx = event->ctx; |
| 262 | u64 run_end; |
| 263 | |
| 264 | if (event->state < PERF_EVENT_STATE_INACTIVE || |
| 265 | event->group_leader->state < PERF_EVENT_STATE_INACTIVE) |
| 266 | return; |
| 267 | |
Peter Zijlstra | acd1d7c | 2009-11-23 15:00:36 +0100 | [diff] [blame] | 268 | if (ctx->is_active) |
| 269 | run_end = ctx->time; |
| 270 | else |
| 271 | run_end = event->tstamp_stopped; |
| 272 | |
| 273 | event->total_time_enabled = run_end - event->tstamp_enabled; |
Peter Zijlstra | f67218c | 2009-11-23 11:37:27 +0100 | [diff] [blame] | 274 | |
| 275 | if (event->state == PERF_EVENT_STATE_INACTIVE) |
| 276 | run_end = event->tstamp_stopped; |
| 277 | else |
| 278 | run_end = ctx->time; |
| 279 | |
| 280 | event->total_time_running = run_end - event->tstamp_running; |
| 281 | } |
| 282 | |
Peter Zijlstra | 96c21a4 | 2010-05-11 16:19:10 +0200 | [diff] [blame] | 283 | /* |
| 284 | * Update total_time_enabled and total_time_running for all events in a group. |
| 285 | */ |
| 286 | static void update_group_times(struct perf_event *leader) |
| 287 | { |
| 288 | struct perf_event *event; |
| 289 | |
| 290 | update_event_times(leader); |
| 291 | list_for_each_entry(event, &leader->sibling_list, group_entry) |
| 292 | update_event_times(event); |
| 293 | } |
| 294 | |
Frederic Weisbecker | 889ff01 | 2010-01-09 20:04:47 +0100 | [diff] [blame] | 295 | static struct list_head * |
| 296 | ctx_group_list(struct perf_event *event, struct perf_event_context *ctx) |
| 297 | { |
| 298 | if (event->attr.pinned) |
| 299 | return &ctx->pinned_groups; |
| 300 | else |
| 301 | return &ctx->flexible_groups; |
| 302 | } |
| 303 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 304 | /* |
| 305 | * Add a event from the lists for its context. |
| 306 | * Must be called with ctx->mutex and ctx->lock held. |
| 307 | */ |
| 308 | static void |
| 309 | list_add_event(struct perf_event *event, struct perf_event_context *ctx) |
| 310 | { |
Peter Zijlstra | 8a49542 | 2010-05-27 15:47:49 +0200 | [diff] [blame] | 311 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); |
| 312 | event->attach_state |= PERF_ATTACH_CONTEXT; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 313 | |
| 314 | /* |
Peter Zijlstra | 8a49542 | 2010-05-27 15:47:49 +0200 | [diff] [blame] | 315 | * If we're a stand alone event or group leader, we go to the context |
| 316 | * list, group events are kept attached to the group so that |
| 317 | * perf_group_detach can, at all times, locate all siblings. |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 318 | */ |
Peter Zijlstra | 8a49542 | 2010-05-27 15:47:49 +0200 | [diff] [blame] | 319 | if (event->group_leader == event) { |
Frederic Weisbecker | 889ff01 | 2010-01-09 20:04:47 +0100 | [diff] [blame] | 320 | struct list_head *list; |
| 321 | |
Frederic Weisbecker | d6f962b | 2010-01-10 01:25:51 +0100 | [diff] [blame] | 322 | if (is_software_event(event)) |
| 323 | event->group_flags |= PERF_GROUP_SOFTWARE; |
| 324 | |
Frederic Weisbecker | 889ff01 | 2010-01-09 20:04:47 +0100 | [diff] [blame] | 325 | list = ctx_group_list(event, ctx); |
| 326 | list_add_tail(&event->group_entry, list); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 327 | } |
| 328 | |
| 329 | list_add_rcu(&event->event_entry, &ctx->event_list); |
Peter Zijlstra | b5ab4cd | 2010-09-06 16:32:21 +0200 | [diff] [blame] | 330 | if (!ctx->nr_events) |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 331 | perf_pmu_rotate_start(ctx->pmu); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 332 | ctx->nr_events++; |
| 333 | if (event->attr.inherit_stat) |
| 334 | ctx->nr_stat++; |
| 335 | } |
| 336 | |
Arnaldo Carvalho de Melo | c320c7b | 2010-10-20 12:50:11 -0200 | [diff] [blame] | 337 | /* |
| 338 | * Called at perf_event creation and when events are attached/detached from a |
| 339 | * group. |
| 340 | */ |
| 341 | static void perf_event__read_size(struct perf_event *event) |
| 342 | { |
| 343 | int entry = sizeof(u64); /* value */ |
| 344 | int size = 0; |
| 345 | int nr = 1; |
| 346 | |
| 347 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) |
| 348 | size += sizeof(u64); |
| 349 | |
| 350 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) |
| 351 | size += sizeof(u64); |
| 352 | |
| 353 | if (event->attr.read_format & PERF_FORMAT_ID) |
| 354 | entry += sizeof(u64); |
| 355 | |
| 356 | if (event->attr.read_format & PERF_FORMAT_GROUP) { |
| 357 | nr += event->group_leader->nr_siblings; |
| 358 | size += sizeof(u64); |
| 359 | } |
| 360 | |
| 361 | size += entry * nr; |
| 362 | event->read_size = size; |
| 363 | } |
| 364 | |
| 365 | static void perf_event__header_size(struct perf_event *event) |
| 366 | { |
| 367 | struct perf_sample_data *data; |
| 368 | u64 sample_type = event->attr.sample_type; |
| 369 | u16 size = 0; |
| 370 | |
| 371 | perf_event__read_size(event); |
| 372 | |
| 373 | if (sample_type & PERF_SAMPLE_IP) |
| 374 | size += sizeof(data->ip); |
| 375 | |
Arnaldo Carvalho de Melo | 6844c09 | 2010-12-03 16:36:35 -0200 | [diff] [blame^] | 376 | if (sample_type & PERF_SAMPLE_ADDR) |
| 377 | size += sizeof(data->addr); |
| 378 | |
| 379 | if (sample_type & PERF_SAMPLE_PERIOD) |
| 380 | size += sizeof(data->period); |
| 381 | |
| 382 | if (sample_type & PERF_SAMPLE_READ) |
| 383 | size += event->read_size; |
| 384 | |
| 385 | event->header_size = size; |
| 386 | } |
| 387 | |
| 388 | static void perf_event__id_header_size(struct perf_event *event) |
| 389 | { |
| 390 | struct perf_sample_data *data; |
| 391 | u64 sample_type = event->attr.sample_type; |
| 392 | u16 size = 0; |
| 393 | |
Arnaldo Carvalho de Melo | c320c7b | 2010-10-20 12:50:11 -0200 | [diff] [blame] | 394 | if (sample_type & PERF_SAMPLE_TID) |
| 395 | size += sizeof(data->tid_entry); |
| 396 | |
| 397 | if (sample_type & PERF_SAMPLE_TIME) |
| 398 | size += sizeof(data->time); |
| 399 | |
Arnaldo Carvalho de Melo | c320c7b | 2010-10-20 12:50:11 -0200 | [diff] [blame] | 400 | if (sample_type & PERF_SAMPLE_ID) |
| 401 | size += sizeof(data->id); |
| 402 | |
| 403 | if (sample_type & PERF_SAMPLE_STREAM_ID) |
| 404 | size += sizeof(data->stream_id); |
| 405 | |
| 406 | if (sample_type & PERF_SAMPLE_CPU) |
| 407 | size += sizeof(data->cpu_entry); |
| 408 | |
Arnaldo Carvalho de Melo | 6844c09 | 2010-12-03 16:36:35 -0200 | [diff] [blame^] | 409 | event->id_header_size = size; |
Arnaldo Carvalho de Melo | c320c7b | 2010-10-20 12:50:11 -0200 | [diff] [blame] | 410 | } |
| 411 | |
Peter Zijlstra | 8a49542 | 2010-05-27 15:47:49 +0200 | [diff] [blame] | 412 | static void perf_group_attach(struct perf_event *event) |
| 413 | { |
Arnaldo Carvalho de Melo | c320c7b | 2010-10-20 12:50:11 -0200 | [diff] [blame] | 414 | struct perf_event *group_leader = event->group_leader, *pos; |
Peter Zijlstra | 8a49542 | 2010-05-27 15:47:49 +0200 | [diff] [blame] | 415 | |
Peter Zijlstra | 74c3337 | 2010-10-15 11:40:29 +0200 | [diff] [blame] | 416 | /* |
| 417 | * We can have double attach due to group movement in perf_event_open. |
| 418 | */ |
| 419 | if (event->attach_state & PERF_ATTACH_GROUP) |
| 420 | return; |
| 421 | |
Peter Zijlstra | 8a49542 | 2010-05-27 15:47:49 +0200 | [diff] [blame] | 422 | event->attach_state |= PERF_ATTACH_GROUP; |
| 423 | |
| 424 | if (group_leader == event) |
| 425 | return; |
| 426 | |
| 427 | if (group_leader->group_flags & PERF_GROUP_SOFTWARE && |
| 428 | !is_software_event(event)) |
| 429 | group_leader->group_flags &= ~PERF_GROUP_SOFTWARE; |
| 430 | |
| 431 | list_add_tail(&event->group_entry, &group_leader->sibling_list); |
| 432 | group_leader->nr_siblings++; |
Arnaldo Carvalho de Melo | c320c7b | 2010-10-20 12:50:11 -0200 | [diff] [blame] | 433 | |
| 434 | perf_event__header_size(group_leader); |
| 435 | |
| 436 | list_for_each_entry(pos, &group_leader->sibling_list, group_entry) |
| 437 | perf_event__header_size(pos); |
Peter Zijlstra | 8a49542 | 2010-05-27 15:47:49 +0200 | [diff] [blame] | 438 | } |
| 439 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 440 | /* |
| 441 | * Remove a event from the lists for its context. |
| 442 | * Must be called with ctx->mutex and ctx->lock held. |
| 443 | */ |
| 444 | static void |
| 445 | list_del_event(struct perf_event *event, struct perf_event_context *ctx) |
| 446 | { |
Peter Zijlstra | 8a49542 | 2010-05-27 15:47:49 +0200 | [diff] [blame] | 447 | /* |
| 448 | * We can have double detach due to exit/hot-unplug + close. |
| 449 | */ |
| 450 | if (!(event->attach_state & PERF_ATTACH_CONTEXT)) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 451 | return; |
Peter Zijlstra | 8a49542 | 2010-05-27 15:47:49 +0200 | [diff] [blame] | 452 | |
| 453 | event->attach_state &= ~PERF_ATTACH_CONTEXT; |
| 454 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 455 | ctx->nr_events--; |
| 456 | if (event->attr.inherit_stat) |
| 457 | ctx->nr_stat--; |
| 458 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 459 | list_del_rcu(&event->event_entry); |
| 460 | |
Peter Zijlstra | 8a49542 | 2010-05-27 15:47:49 +0200 | [diff] [blame] | 461 | if (event->group_leader == event) |
| 462 | list_del_init(&event->group_entry); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 463 | |
Peter Zijlstra | 96c21a4 | 2010-05-11 16:19:10 +0200 | [diff] [blame] | 464 | update_group_times(event); |
Stephane Eranian | b2e74a2 | 2009-11-26 09:24:30 -0800 | [diff] [blame] | 465 | |
| 466 | /* |
| 467 | * If event was in error state, then keep it |
| 468 | * that way, otherwise bogus counts will be |
| 469 | * returned on read(). The only way to get out |
| 470 | * of error state is by explicit re-enabling |
| 471 | * of the event |
| 472 | */ |
| 473 | if (event->state > PERF_EVENT_STATE_OFF) |
| 474 | event->state = PERF_EVENT_STATE_OFF; |
Peter Zijlstra | 050735b | 2010-05-11 11:51:53 +0200 | [diff] [blame] | 475 | } |
| 476 | |
Peter Zijlstra | 8a49542 | 2010-05-27 15:47:49 +0200 | [diff] [blame] | 477 | static void perf_group_detach(struct perf_event *event) |
Peter Zijlstra | 050735b | 2010-05-11 11:51:53 +0200 | [diff] [blame] | 478 | { |
| 479 | struct perf_event *sibling, *tmp; |
Peter Zijlstra | 8a49542 | 2010-05-27 15:47:49 +0200 | [diff] [blame] | 480 | struct list_head *list = NULL; |
| 481 | |
| 482 | /* |
| 483 | * We can have double detach due to exit/hot-unplug + close. |
| 484 | */ |
| 485 | if (!(event->attach_state & PERF_ATTACH_GROUP)) |
| 486 | return; |
| 487 | |
| 488 | event->attach_state &= ~PERF_ATTACH_GROUP; |
| 489 | |
| 490 | /* |
| 491 | * If this is a sibling, remove it from its group. |
| 492 | */ |
| 493 | if (event->group_leader != event) { |
| 494 | list_del_init(&event->group_entry); |
| 495 | event->group_leader->nr_siblings--; |
Arnaldo Carvalho de Melo | c320c7b | 2010-10-20 12:50:11 -0200 | [diff] [blame] | 496 | goto out; |
Peter Zijlstra | 8a49542 | 2010-05-27 15:47:49 +0200 | [diff] [blame] | 497 | } |
| 498 | |
| 499 | if (!list_empty(&event->group_entry)) |
| 500 | list = &event->group_entry; |
Peter Zijlstra | 2e2af50 | 2009-11-23 11:37:25 +0100 | [diff] [blame] | 501 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 502 | /* |
| 503 | * If this was a group event with sibling events then |
| 504 | * upgrade the siblings to singleton events by adding them |
Peter Zijlstra | 8a49542 | 2010-05-27 15:47:49 +0200 | [diff] [blame] | 505 | * to whatever list we are on. |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 506 | */ |
| 507 | list_for_each_entry_safe(sibling, tmp, &event->sibling_list, group_entry) { |
Peter Zijlstra | 8a49542 | 2010-05-27 15:47:49 +0200 | [diff] [blame] | 508 | if (list) |
| 509 | list_move_tail(&sibling->group_entry, list); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 510 | sibling->group_leader = sibling; |
Frederic Weisbecker | d6f962b | 2010-01-10 01:25:51 +0100 | [diff] [blame] | 511 | |
| 512 | /* Inherit group flags from the previous leader */ |
| 513 | sibling->group_flags = event->group_flags; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 514 | } |
Arnaldo Carvalho de Melo | c320c7b | 2010-10-20 12:50:11 -0200 | [diff] [blame] | 515 | |
| 516 | out: |
| 517 | perf_event__header_size(event->group_leader); |
| 518 | |
| 519 | list_for_each_entry(tmp, &event->group_leader->sibling_list, group_entry) |
| 520 | perf_event__header_size(tmp); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 521 | } |
| 522 | |
Stephane Eranian | fa66f07 | 2010-08-26 16:40:01 +0200 | [diff] [blame] | 523 | static inline int |
| 524 | event_filter_match(struct perf_event *event) |
| 525 | { |
| 526 | return event->cpu == -1 || event->cpu == smp_processor_id(); |
| 527 | } |
| 528 | |
Stephane Eranian | 9ffcfa6 | 2010-10-20 15:25:01 +0200 | [diff] [blame] | 529 | static void |
| 530 | event_sched_out(struct perf_event *event, |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 531 | struct perf_cpu_context *cpuctx, |
| 532 | struct perf_event_context *ctx) |
| 533 | { |
Stephane Eranian | fa66f07 | 2010-08-26 16:40:01 +0200 | [diff] [blame] | 534 | u64 delta; |
| 535 | /* |
| 536 | * An event which could not be activated because of |
| 537 | * filter mismatch still needs to have its timings |
| 538 | * maintained, otherwise bogus information is return |
| 539 | * via read() for time_enabled, time_running: |
| 540 | */ |
| 541 | if (event->state == PERF_EVENT_STATE_INACTIVE |
| 542 | && !event_filter_match(event)) { |
| 543 | delta = ctx->time - event->tstamp_stopped; |
| 544 | event->tstamp_running += delta; |
| 545 | event->tstamp_stopped = ctx->time; |
| 546 | } |
| 547 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 548 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
Stephane Eranian | 9ffcfa6 | 2010-10-20 15:25:01 +0200 | [diff] [blame] | 549 | return; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 550 | |
| 551 | event->state = PERF_EVENT_STATE_INACTIVE; |
| 552 | if (event->pending_disable) { |
| 553 | event->pending_disable = 0; |
| 554 | event->state = PERF_EVENT_STATE_OFF; |
| 555 | } |
Stephane Eranian | 9ffcfa6 | 2010-10-20 15:25:01 +0200 | [diff] [blame] | 556 | event->tstamp_stopped = ctx->time; |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 557 | event->pmu->del(event, 0); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 558 | event->oncpu = -1; |
| 559 | |
| 560 | if (!is_software_event(event)) |
| 561 | cpuctx->active_oncpu--; |
| 562 | ctx->nr_active--; |
| 563 | if (event->attr.exclusive || !cpuctx->active_oncpu) |
| 564 | cpuctx->exclusive = 0; |
| 565 | } |
| 566 | |
| 567 | static void |
| 568 | group_sched_out(struct perf_event *group_event, |
| 569 | struct perf_cpu_context *cpuctx, |
| 570 | struct perf_event_context *ctx) |
| 571 | { |
| 572 | struct perf_event *event; |
Stephane Eranian | fa66f07 | 2010-08-26 16:40:01 +0200 | [diff] [blame] | 573 | int state = group_event->state; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 574 | |
| 575 | event_sched_out(group_event, cpuctx, ctx); |
| 576 | |
| 577 | /* |
| 578 | * Schedule out siblings (if any): |
| 579 | */ |
| 580 | list_for_each_entry(event, &group_event->sibling_list, group_entry) |
| 581 | event_sched_out(event, cpuctx, ctx); |
| 582 | |
Stephane Eranian | fa66f07 | 2010-08-26 16:40:01 +0200 | [diff] [blame] | 583 | if (state == PERF_EVENT_STATE_ACTIVE && group_event->attr.exclusive) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 584 | cpuctx->exclusive = 0; |
| 585 | } |
| 586 | |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 587 | static inline struct perf_cpu_context * |
| 588 | __get_cpu_context(struct perf_event_context *ctx) |
| 589 | { |
| 590 | return this_cpu_ptr(ctx->pmu->pmu_cpu_context); |
| 591 | } |
| 592 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 593 | /* |
| 594 | * Cross CPU call to remove a performance event |
| 595 | * |
| 596 | * We disable the event on the hardware level first. After that we |
| 597 | * remove it from the context list. |
| 598 | */ |
| 599 | static void __perf_event_remove_from_context(void *info) |
| 600 | { |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 601 | struct perf_event *event = info; |
| 602 | struct perf_event_context *ctx = event->ctx; |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 603 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 604 | |
| 605 | /* |
| 606 | * If this is a task context, we need to check whether it is |
| 607 | * the current task context of this cpu. If not it has been |
| 608 | * scheduled out before the smp call arrived. |
| 609 | */ |
| 610 | if (ctx->task && cpuctx->task_ctx != ctx) |
| 611 | return; |
| 612 | |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 613 | raw_spin_lock(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 614 | |
| 615 | event_sched_out(event, cpuctx, ctx); |
| 616 | |
| 617 | list_del_event(event, ctx); |
| 618 | |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 619 | raw_spin_unlock(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 620 | } |
| 621 | |
| 622 | |
| 623 | /* |
| 624 | * Remove the event from a task's (or a CPU's) list of events. |
| 625 | * |
| 626 | * Must be called with ctx->mutex held. |
| 627 | * |
| 628 | * CPU events are removed with a smp call. For task events we only |
| 629 | * call when the task is on a CPU. |
| 630 | * |
| 631 | * If event->ctx is a cloned context, callers must make sure that |
| 632 | * every task struct that event->ctx->task could possibly point to |
| 633 | * remains valid. This is OK when called from perf_release since |
| 634 | * that only calls us on the top-level context, which can't be a clone. |
| 635 | * When called from perf_event_exit_task, it's OK because the |
| 636 | * context has been detached from its task. |
| 637 | */ |
| 638 | static void perf_event_remove_from_context(struct perf_event *event) |
| 639 | { |
| 640 | struct perf_event_context *ctx = event->ctx; |
| 641 | struct task_struct *task = ctx->task; |
| 642 | |
| 643 | if (!task) { |
| 644 | /* |
| 645 | * Per cpu events are removed via an smp call and |
André Goddard Rosa | af901ca | 2009-11-14 13:09:05 -0200 | [diff] [blame] | 646 | * the removal is always successful. |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 647 | */ |
| 648 | smp_call_function_single(event->cpu, |
| 649 | __perf_event_remove_from_context, |
| 650 | event, 1); |
| 651 | return; |
| 652 | } |
| 653 | |
| 654 | retry: |
| 655 | task_oncpu_function_call(task, __perf_event_remove_from_context, |
| 656 | event); |
| 657 | |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 658 | raw_spin_lock_irq(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 659 | /* |
| 660 | * If the context is active we need to retry the smp call. |
| 661 | */ |
| 662 | if (ctx->nr_active && !list_empty(&event->group_entry)) { |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 663 | raw_spin_unlock_irq(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 664 | goto retry; |
| 665 | } |
| 666 | |
| 667 | /* |
| 668 | * The lock prevents that this context is scheduled in so we |
| 669 | * can remove the event safely, if the call above did not |
| 670 | * succeed. |
| 671 | */ |
Peter Zijlstra | 6c2bfcb | 2009-11-23 11:37:24 +0100 | [diff] [blame] | 672 | if (!list_empty(&event->group_entry)) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 673 | list_del_event(event, ctx); |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 674 | raw_spin_unlock_irq(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 675 | } |
| 676 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 677 | /* |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 678 | * Cross CPU call to disable a performance event |
| 679 | */ |
| 680 | static void __perf_event_disable(void *info) |
| 681 | { |
| 682 | struct perf_event *event = info; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 683 | struct perf_event_context *ctx = event->ctx; |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 684 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 685 | |
| 686 | /* |
| 687 | * If this is a per-task event, need to check whether this |
| 688 | * event's task is the current task on this cpu. |
| 689 | */ |
| 690 | if (ctx->task && cpuctx->task_ctx != ctx) |
| 691 | return; |
| 692 | |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 693 | raw_spin_lock(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 694 | |
| 695 | /* |
| 696 | * If the event is on, turn it off. |
| 697 | * If it is in error state, leave it in error state. |
| 698 | */ |
| 699 | if (event->state >= PERF_EVENT_STATE_INACTIVE) { |
| 700 | update_context_time(ctx); |
| 701 | update_group_times(event); |
| 702 | if (event == event->group_leader) |
| 703 | group_sched_out(event, cpuctx, ctx); |
| 704 | else |
| 705 | event_sched_out(event, cpuctx, ctx); |
| 706 | event->state = PERF_EVENT_STATE_OFF; |
| 707 | } |
| 708 | |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 709 | raw_spin_unlock(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 710 | } |
| 711 | |
| 712 | /* |
| 713 | * Disable a event. |
| 714 | * |
| 715 | * If event->ctx is a cloned context, callers must make sure that |
| 716 | * every task struct that event->ctx->task could possibly point to |
| 717 | * remains valid. This condition is satisifed when called through |
| 718 | * perf_event_for_each_child or perf_event_for_each because they |
| 719 | * hold the top-level event's child_mutex, so any descendant that |
| 720 | * goes to exit will block in sync_child_event. |
| 721 | * When called from perf_pending_event it's OK because event->ctx |
| 722 | * is the current context on this CPU and preemption is disabled, |
| 723 | * hence we can't get into perf_event_task_sched_out for this context. |
| 724 | */ |
Frederic Weisbecker | 44234ad | 2009-12-09 09:25:48 +0100 | [diff] [blame] | 725 | void perf_event_disable(struct perf_event *event) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 726 | { |
| 727 | struct perf_event_context *ctx = event->ctx; |
| 728 | struct task_struct *task = ctx->task; |
| 729 | |
| 730 | if (!task) { |
| 731 | /* |
| 732 | * Disable the event on the cpu that it's on |
| 733 | */ |
| 734 | smp_call_function_single(event->cpu, __perf_event_disable, |
| 735 | event, 1); |
| 736 | return; |
| 737 | } |
| 738 | |
Peter Zijlstra | 9ed6060 | 2010-06-11 17:36:35 +0200 | [diff] [blame] | 739 | retry: |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 740 | task_oncpu_function_call(task, __perf_event_disable, event); |
| 741 | |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 742 | raw_spin_lock_irq(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 743 | /* |
| 744 | * If the event is still active, we need to retry the cross-call. |
| 745 | */ |
| 746 | if (event->state == PERF_EVENT_STATE_ACTIVE) { |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 747 | raw_spin_unlock_irq(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 748 | goto retry; |
| 749 | } |
| 750 | |
| 751 | /* |
| 752 | * Since we have the lock this context can't be scheduled |
| 753 | * in, so we can change the state safely. |
| 754 | */ |
| 755 | if (event->state == PERF_EVENT_STATE_INACTIVE) { |
| 756 | update_group_times(event); |
| 757 | event->state = PERF_EVENT_STATE_OFF; |
| 758 | } |
| 759 | |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 760 | raw_spin_unlock_irq(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 761 | } |
| 762 | |
| 763 | static int |
Stephane Eranian | 9ffcfa6 | 2010-10-20 15:25:01 +0200 | [diff] [blame] | 764 | event_sched_in(struct perf_event *event, |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 765 | struct perf_cpu_context *cpuctx, |
Peter Zijlstra | 6e37738 | 2010-02-11 13:21:58 +0100 | [diff] [blame] | 766 | struct perf_event_context *ctx) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 767 | { |
| 768 | if (event->state <= PERF_EVENT_STATE_OFF) |
| 769 | return 0; |
| 770 | |
| 771 | event->state = PERF_EVENT_STATE_ACTIVE; |
Peter Zijlstra | 6e37738 | 2010-02-11 13:21:58 +0100 | [diff] [blame] | 772 | event->oncpu = smp_processor_id(); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 773 | /* |
| 774 | * The new state must be visible before we turn it on in the hardware: |
| 775 | */ |
| 776 | smp_wmb(); |
| 777 | |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 778 | if (event->pmu->add(event, PERF_EF_START)) { |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 779 | event->state = PERF_EVENT_STATE_INACTIVE; |
| 780 | event->oncpu = -1; |
| 781 | return -EAGAIN; |
| 782 | } |
| 783 | |
Stephane Eranian | 9ffcfa6 | 2010-10-20 15:25:01 +0200 | [diff] [blame] | 784 | event->tstamp_running += ctx->time - event->tstamp_stopped; |
| 785 | |
Stephane Eranian | eed0152 | 2010-10-26 16:08:01 +0200 | [diff] [blame] | 786 | event->shadow_ctx_time = ctx->time - ctx->timestamp; |
| 787 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 788 | if (!is_software_event(event)) |
| 789 | cpuctx->active_oncpu++; |
| 790 | ctx->nr_active++; |
| 791 | |
| 792 | if (event->attr.exclusive) |
| 793 | cpuctx->exclusive = 1; |
| 794 | |
| 795 | return 0; |
| 796 | } |
| 797 | |
| 798 | static int |
| 799 | group_sched_in(struct perf_event *group_event, |
| 800 | struct perf_cpu_context *cpuctx, |
Peter Zijlstra | 6e37738 | 2010-02-11 13:21:58 +0100 | [diff] [blame] | 801 | struct perf_event_context *ctx) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 802 | { |
Lin Ming | 6bde9b6 | 2010-04-23 13:56:00 +0800 | [diff] [blame] | 803 | struct perf_event *event, *partial_group = NULL; |
Peter Zijlstra | 51b0fe3 | 2010-06-11 13:35:57 +0200 | [diff] [blame] | 804 | struct pmu *pmu = group_event->pmu; |
Stephane Eranian | d7842da | 2010-10-20 15:25:01 +0200 | [diff] [blame] | 805 | u64 now = ctx->time; |
| 806 | bool simulate = false; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 807 | |
| 808 | if (group_event->state == PERF_EVENT_STATE_OFF) |
| 809 | return 0; |
| 810 | |
Peter Zijlstra | ad5133b | 2010-06-15 12:22:39 +0200 | [diff] [blame] | 811 | pmu->start_txn(pmu); |
Lin Ming | 6bde9b6 | 2010-04-23 13:56:00 +0800 | [diff] [blame] | 812 | |
Stephane Eranian | 9ffcfa6 | 2010-10-20 15:25:01 +0200 | [diff] [blame] | 813 | if (event_sched_in(group_event, cpuctx, ctx)) { |
Peter Zijlstra | ad5133b | 2010-06-15 12:22:39 +0200 | [diff] [blame] | 814 | pmu->cancel_txn(pmu); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 815 | return -EAGAIN; |
Stephane Eranian | 90151c35 | 2010-05-25 16:23:10 +0200 | [diff] [blame] | 816 | } |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 817 | |
| 818 | /* |
| 819 | * Schedule in siblings as one group (if any): |
| 820 | */ |
| 821 | list_for_each_entry(event, &group_event->sibling_list, group_entry) { |
Stephane Eranian | 9ffcfa6 | 2010-10-20 15:25:01 +0200 | [diff] [blame] | 822 | if (event_sched_in(event, cpuctx, ctx)) { |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 823 | partial_group = event; |
| 824 | goto group_error; |
| 825 | } |
| 826 | } |
| 827 | |
Stephane Eranian | 9ffcfa6 | 2010-10-20 15:25:01 +0200 | [diff] [blame] | 828 | if (!pmu->commit_txn(pmu)) |
Paul Mackerras | 6e85158 | 2010-05-08 20:58:00 +1000 | [diff] [blame] | 829 | return 0; |
Stephane Eranian | 9ffcfa6 | 2010-10-20 15:25:01 +0200 | [diff] [blame] | 830 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 831 | group_error: |
| 832 | /* |
| 833 | * Groups can be scheduled in as one unit only, so undo any |
| 834 | * partial group before returning: |
Stephane Eranian | d7842da | 2010-10-20 15:25:01 +0200 | [diff] [blame] | 835 | * The events up to the failed event are scheduled out normally, |
| 836 | * tstamp_stopped will be updated. |
| 837 | * |
| 838 | * The failed events and the remaining siblings need to have |
| 839 | * their timings updated as if they had gone thru event_sched_in() |
| 840 | * and event_sched_out(). This is required to get consistent timings |
| 841 | * across the group. This also takes care of the case where the group |
| 842 | * could never be scheduled by ensuring tstamp_stopped is set to mark |
| 843 | * the time the event was actually stopped, such that time delta |
| 844 | * calculation in update_event_times() is correct. |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 845 | */ |
| 846 | list_for_each_entry(event, &group_event->sibling_list, group_entry) { |
| 847 | if (event == partial_group) |
Stephane Eranian | d7842da | 2010-10-20 15:25:01 +0200 | [diff] [blame] | 848 | simulate = true; |
| 849 | |
| 850 | if (simulate) { |
| 851 | event->tstamp_running += now - event->tstamp_stopped; |
| 852 | event->tstamp_stopped = now; |
| 853 | } else { |
| 854 | event_sched_out(event, cpuctx, ctx); |
| 855 | } |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 856 | } |
Stephane Eranian | 9ffcfa6 | 2010-10-20 15:25:01 +0200 | [diff] [blame] | 857 | event_sched_out(group_event, cpuctx, ctx); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 858 | |
Peter Zijlstra | ad5133b | 2010-06-15 12:22:39 +0200 | [diff] [blame] | 859 | pmu->cancel_txn(pmu); |
Stephane Eranian | 90151c35 | 2010-05-25 16:23:10 +0200 | [diff] [blame] | 860 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 861 | return -EAGAIN; |
| 862 | } |
| 863 | |
| 864 | /* |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 865 | * Work out whether we can put this event group on the CPU now. |
| 866 | */ |
| 867 | static int group_can_go_on(struct perf_event *event, |
| 868 | struct perf_cpu_context *cpuctx, |
| 869 | int can_add_hw) |
| 870 | { |
| 871 | /* |
| 872 | * Groups consisting entirely of software events can always go on. |
| 873 | */ |
Frederic Weisbecker | d6f962b | 2010-01-10 01:25:51 +0100 | [diff] [blame] | 874 | if (event->group_flags & PERF_GROUP_SOFTWARE) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 875 | return 1; |
| 876 | /* |
| 877 | * If an exclusive group is already on, no other hardware |
| 878 | * events can go on. |
| 879 | */ |
| 880 | if (cpuctx->exclusive) |
| 881 | return 0; |
| 882 | /* |
| 883 | * If this group is exclusive and there are already |
| 884 | * events on the CPU, it can't go on. |
| 885 | */ |
| 886 | if (event->attr.exclusive && cpuctx->active_oncpu) |
| 887 | return 0; |
| 888 | /* |
| 889 | * Otherwise, try to add it if all previous groups were able |
| 890 | * to go on. |
| 891 | */ |
| 892 | return can_add_hw; |
| 893 | } |
| 894 | |
| 895 | static void add_event_to_ctx(struct perf_event *event, |
| 896 | struct perf_event_context *ctx) |
| 897 | { |
| 898 | list_add_event(event, ctx); |
Peter Zijlstra | 8a49542 | 2010-05-27 15:47:49 +0200 | [diff] [blame] | 899 | perf_group_attach(event); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 900 | event->tstamp_enabled = ctx->time; |
| 901 | event->tstamp_running = ctx->time; |
| 902 | event->tstamp_stopped = ctx->time; |
| 903 | } |
| 904 | |
| 905 | /* |
| 906 | * Cross CPU call to install and enable a performance event |
| 907 | * |
| 908 | * Must be called with ctx->mutex held |
| 909 | */ |
| 910 | static void __perf_install_in_context(void *info) |
| 911 | { |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 912 | struct perf_event *event = info; |
| 913 | struct perf_event_context *ctx = event->ctx; |
| 914 | struct perf_event *leader = event->group_leader; |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 915 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 916 | int err; |
| 917 | |
| 918 | /* |
| 919 | * If this is a task context, we need to check whether it is |
| 920 | * the current task context of this cpu. If not it has been |
| 921 | * scheduled out before the smp call arrived. |
| 922 | * Or possibly this is the right context but it isn't |
| 923 | * on this cpu because it had no events. |
| 924 | */ |
| 925 | if (ctx->task && cpuctx->task_ctx != ctx) { |
| 926 | if (cpuctx->task_ctx || ctx->task != current) |
| 927 | return; |
| 928 | cpuctx->task_ctx = ctx; |
| 929 | } |
| 930 | |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 931 | raw_spin_lock(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 932 | ctx->is_active = 1; |
| 933 | update_context_time(ctx); |
| 934 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 935 | add_event_to_ctx(event, ctx); |
| 936 | |
Peter Zijlstra | f4c4176 | 2009-12-16 17:55:54 +0100 | [diff] [blame] | 937 | if (event->cpu != -1 && event->cpu != smp_processor_id()) |
| 938 | goto unlock; |
| 939 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 940 | /* |
| 941 | * Don't put the event on if it is disabled or if |
| 942 | * it is in a group and the group isn't on. |
| 943 | */ |
| 944 | if (event->state != PERF_EVENT_STATE_INACTIVE || |
| 945 | (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE)) |
| 946 | goto unlock; |
| 947 | |
| 948 | /* |
| 949 | * An exclusive event can't go on if there are already active |
| 950 | * hardware events, and no hardware event can go on if there |
| 951 | * is already an exclusive event on. |
| 952 | */ |
| 953 | if (!group_can_go_on(event, cpuctx, 1)) |
| 954 | err = -EEXIST; |
| 955 | else |
Peter Zijlstra | 6e37738 | 2010-02-11 13:21:58 +0100 | [diff] [blame] | 956 | err = event_sched_in(event, cpuctx, ctx); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 957 | |
| 958 | if (err) { |
| 959 | /* |
| 960 | * This event couldn't go on. If it is in a group |
| 961 | * then we have to pull the whole group off. |
| 962 | * If the event group is pinned then put it in error state. |
| 963 | */ |
| 964 | if (leader != event) |
| 965 | group_sched_out(leader, cpuctx, ctx); |
| 966 | if (leader->attr.pinned) { |
| 967 | update_group_times(leader); |
| 968 | leader->state = PERF_EVENT_STATE_ERROR; |
| 969 | } |
| 970 | } |
| 971 | |
Peter Zijlstra | 9ed6060 | 2010-06-11 17:36:35 +0200 | [diff] [blame] | 972 | unlock: |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 973 | raw_spin_unlock(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 974 | } |
| 975 | |
| 976 | /* |
| 977 | * Attach a performance event to a context |
| 978 | * |
| 979 | * First we add the event to the list with the hardware enable bit |
| 980 | * in event->hw_config cleared. |
| 981 | * |
| 982 | * If the event is attached to a task which is on a CPU we use a smp |
| 983 | * call to enable it in the task context. The task might have been |
| 984 | * scheduled away, but we check this in the smp call again. |
| 985 | * |
| 986 | * Must be called with ctx->mutex held. |
| 987 | */ |
| 988 | static void |
| 989 | perf_install_in_context(struct perf_event_context *ctx, |
| 990 | struct perf_event *event, |
| 991 | int cpu) |
| 992 | { |
| 993 | struct task_struct *task = ctx->task; |
| 994 | |
Peter Zijlstra | c3f00c7 | 2010-08-18 14:37:15 +0200 | [diff] [blame] | 995 | event->ctx = ctx; |
| 996 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 997 | if (!task) { |
| 998 | /* |
| 999 | * Per cpu events are installed via an smp call and |
André Goddard Rosa | af901ca | 2009-11-14 13:09:05 -0200 | [diff] [blame] | 1000 | * the install is always successful. |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1001 | */ |
| 1002 | smp_call_function_single(cpu, __perf_install_in_context, |
| 1003 | event, 1); |
| 1004 | return; |
| 1005 | } |
| 1006 | |
| 1007 | retry: |
| 1008 | task_oncpu_function_call(task, __perf_install_in_context, |
| 1009 | event); |
| 1010 | |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 1011 | raw_spin_lock_irq(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1012 | /* |
| 1013 | * we need to retry the smp call. |
| 1014 | */ |
| 1015 | if (ctx->is_active && list_empty(&event->group_entry)) { |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 1016 | raw_spin_unlock_irq(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1017 | goto retry; |
| 1018 | } |
| 1019 | |
| 1020 | /* |
| 1021 | * The lock prevents that this context is scheduled in so we |
| 1022 | * can add the event safely, if it the call above did not |
| 1023 | * succeed. |
| 1024 | */ |
| 1025 | if (list_empty(&event->group_entry)) |
| 1026 | add_event_to_ctx(event, ctx); |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 1027 | raw_spin_unlock_irq(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1028 | } |
| 1029 | |
| 1030 | /* |
| 1031 | * Put a event into inactive state and update time fields. |
| 1032 | * Enabling the leader of a group effectively enables all |
| 1033 | * the group members that aren't explicitly disabled, so we |
| 1034 | * have to update their ->tstamp_enabled also. |
| 1035 | * Note: this works for group members as well as group leaders |
| 1036 | * since the non-leader members' sibling_lists will be empty. |
| 1037 | */ |
| 1038 | static void __perf_event_mark_enabled(struct perf_event *event, |
| 1039 | struct perf_event_context *ctx) |
| 1040 | { |
| 1041 | struct perf_event *sub; |
| 1042 | |
| 1043 | event->state = PERF_EVENT_STATE_INACTIVE; |
| 1044 | event->tstamp_enabled = ctx->time - event->total_time_enabled; |
Peter Zijlstra | 9ed6060 | 2010-06-11 17:36:35 +0200 | [diff] [blame] | 1045 | list_for_each_entry(sub, &event->sibling_list, group_entry) { |
| 1046 | if (sub->state >= PERF_EVENT_STATE_INACTIVE) { |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1047 | sub->tstamp_enabled = |
| 1048 | ctx->time - sub->total_time_enabled; |
Peter Zijlstra | 9ed6060 | 2010-06-11 17:36:35 +0200 | [diff] [blame] | 1049 | } |
| 1050 | } |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1051 | } |
| 1052 | |
| 1053 | /* |
| 1054 | * Cross CPU call to enable a performance event |
| 1055 | */ |
| 1056 | static void __perf_event_enable(void *info) |
| 1057 | { |
| 1058 | struct perf_event *event = info; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1059 | struct perf_event_context *ctx = event->ctx; |
| 1060 | struct perf_event *leader = event->group_leader; |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 1061 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1062 | int err; |
| 1063 | |
| 1064 | /* |
| 1065 | * If this is a per-task event, need to check whether this |
| 1066 | * event's task is the current task on this cpu. |
| 1067 | */ |
| 1068 | if (ctx->task && cpuctx->task_ctx != ctx) { |
| 1069 | if (cpuctx->task_ctx || ctx->task != current) |
| 1070 | return; |
| 1071 | cpuctx->task_ctx = ctx; |
| 1072 | } |
| 1073 | |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 1074 | raw_spin_lock(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1075 | ctx->is_active = 1; |
| 1076 | update_context_time(ctx); |
| 1077 | |
| 1078 | if (event->state >= PERF_EVENT_STATE_INACTIVE) |
| 1079 | goto unlock; |
| 1080 | __perf_event_mark_enabled(event, ctx); |
| 1081 | |
Peter Zijlstra | f4c4176 | 2009-12-16 17:55:54 +0100 | [diff] [blame] | 1082 | if (event->cpu != -1 && event->cpu != smp_processor_id()) |
| 1083 | goto unlock; |
| 1084 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1085 | /* |
| 1086 | * If the event is in a group and isn't the group leader, |
| 1087 | * then don't put it on unless the group is on. |
| 1088 | */ |
| 1089 | if (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE) |
| 1090 | goto unlock; |
| 1091 | |
| 1092 | if (!group_can_go_on(event, cpuctx, 1)) { |
| 1093 | err = -EEXIST; |
| 1094 | } else { |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1095 | if (event == leader) |
Peter Zijlstra | 6e37738 | 2010-02-11 13:21:58 +0100 | [diff] [blame] | 1096 | err = group_sched_in(event, cpuctx, ctx); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1097 | else |
Peter Zijlstra | 6e37738 | 2010-02-11 13:21:58 +0100 | [diff] [blame] | 1098 | err = event_sched_in(event, cpuctx, ctx); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1099 | } |
| 1100 | |
| 1101 | if (err) { |
| 1102 | /* |
| 1103 | * If this event can't go on and it's part of a |
| 1104 | * group, then the whole group has to come off. |
| 1105 | */ |
| 1106 | if (leader != event) |
| 1107 | group_sched_out(leader, cpuctx, ctx); |
| 1108 | if (leader->attr.pinned) { |
| 1109 | update_group_times(leader); |
| 1110 | leader->state = PERF_EVENT_STATE_ERROR; |
| 1111 | } |
| 1112 | } |
| 1113 | |
Peter Zijlstra | 9ed6060 | 2010-06-11 17:36:35 +0200 | [diff] [blame] | 1114 | unlock: |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 1115 | raw_spin_unlock(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1116 | } |
| 1117 | |
| 1118 | /* |
| 1119 | * Enable a event. |
| 1120 | * |
| 1121 | * If event->ctx is a cloned context, callers must make sure that |
| 1122 | * every task struct that event->ctx->task could possibly point to |
| 1123 | * remains valid. This condition is satisfied when called through |
| 1124 | * perf_event_for_each_child or perf_event_for_each as described |
| 1125 | * for perf_event_disable. |
| 1126 | */ |
Frederic Weisbecker | 44234ad | 2009-12-09 09:25:48 +0100 | [diff] [blame] | 1127 | void perf_event_enable(struct perf_event *event) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1128 | { |
| 1129 | struct perf_event_context *ctx = event->ctx; |
| 1130 | struct task_struct *task = ctx->task; |
| 1131 | |
| 1132 | if (!task) { |
| 1133 | /* |
| 1134 | * Enable the event on the cpu that it's on |
| 1135 | */ |
| 1136 | smp_call_function_single(event->cpu, __perf_event_enable, |
| 1137 | event, 1); |
| 1138 | return; |
| 1139 | } |
| 1140 | |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 1141 | raw_spin_lock_irq(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1142 | if (event->state >= PERF_EVENT_STATE_INACTIVE) |
| 1143 | goto out; |
| 1144 | |
| 1145 | /* |
| 1146 | * If the event is in error state, clear that first. |
| 1147 | * That way, if we see the event in error state below, we |
| 1148 | * know that it has gone back into error state, as distinct |
| 1149 | * from the task having been scheduled away before the |
| 1150 | * cross-call arrived. |
| 1151 | */ |
| 1152 | if (event->state == PERF_EVENT_STATE_ERROR) |
| 1153 | event->state = PERF_EVENT_STATE_OFF; |
| 1154 | |
Peter Zijlstra | 9ed6060 | 2010-06-11 17:36:35 +0200 | [diff] [blame] | 1155 | retry: |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 1156 | raw_spin_unlock_irq(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1157 | task_oncpu_function_call(task, __perf_event_enable, event); |
| 1158 | |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 1159 | raw_spin_lock_irq(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1160 | |
| 1161 | /* |
| 1162 | * If the context is active and the event is still off, |
| 1163 | * we need to retry the cross-call. |
| 1164 | */ |
| 1165 | if (ctx->is_active && event->state == PERF_EVENT_STATE_OFF) |
| 1166 | goto retry; |
| 1167 | |
| 1168 | /* |
| 1169 | * Since we have the lock this context can't be scheduled |
| 1170 | * in, so we can change the state safely. |
| 1171 | */ |
| 1172 | if (event->state == PERF_EVENT_STATE_OFF) |
| 1173 | __perf_event_mark_enabled(event, ctx); |
| 1174 | |
Peter Zijlstra | 9ed6060 | 2010-06-11 17:36:35 +0200 | [diff] [blame] | 1175 | out: |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 1176 | raw_spin_unlock_irq(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1177 | } |
| 1178 | |
| 1179 | static int perf_event_refresh(struct perf_event *event, int refresh) |
| 1180 | { |
| 1181 | /* |
| 1182 | * not supported on inherited events |
| 1183 | */ |
Franck Bui-Huu | 2e939d1 | 2010-11-23 16:21:44 +0100 | [diff] [blame] | 1184 | if (event->attr.inherit || !is_sampling_event(event)) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1185 | return -EINVAL; |
| 1186 | |
| 1187 | atomic_add(refresh, &event->event_limit); |
| 1188 | perf_event_enable(event); |
| 1189 | |
| 1190 | return 0; |
| 1191 | } |
| 1192 | |
Frederic Weisbecker | 5b0311e | 2010-01-17 11:59:13 +0100 | [diff] [blame] | 1193 | enum event_type_t { |
| 1194 | EVENT_FLEXIBLE = 0x1, |
| 1195 | EVENT_PINNED = 0x2, |
| 1196 | EVENT_ALL = EVENT_FLEXIBLE | EVENT_PINNED, |
| 1197 | }; |
| 1198 | |
| 1199 | static void ctx_sched_out(struct perf_event_context *ctx, |
| 1200 | struct perf_cpu_context *cpuctx, |
| 1201 | enum event_type_t event_type) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1202 | { |
| 1203 | struct perf_event *event; |
| 1204 | |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 1205 | raw_spin_lock(&ctx->lock); |
Peter Zijlstra | 1b9a644 | 2010-09-07 18:32:22 +0200 | [diff] [blame] | 1206 | perf_pmu_disable(ctx->pmu); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1207 | ctx->is_active = 0; |
| 1208 | if (likely(!ctx->nr_events)) |
| 1209 | goto out; |
| 1210 | update_context_time(ctx); |
| 1211 | |
Frederic Weisbecker | 5b0311e | 2010-01-17 11:59:13 +0100 | [diff] [blame] | 1212 | if (!ctx->nr_active) |
Peter Zijlstra | 24cd7f5 | 2010-06-11 17:32:03 +0200 | [diff] [blame] | 1213 | goto out; |
Frederic Weisbecker | 5b0311e | 2010-01-17 11:59:13 +0100 | [diff] [blame] | 1214 | |
Peter Zijlstra | 9ed6060 | 2010-06-11 17:36:35 +0200 | [diff] [blame] | 1215 | if (event_type & EVENT_PINNED) { |
Frederic Weisbecker | 889ff01 | 2010-01-09 20:04:47 +0100 | [diff] [blame] | 1216 | list_for_each_entry(event, &ctx->pinned_groups, group_entry) |
| 1217 | group_sched_out(event, cpuctx, ctx); |
Peter Zijlstra | 9ed6060 | 2010-06-11 17:36:35 +0200 | [diff] [blame] | 1218 | } |
Frederic Weisbecker | 889ff01 | 2010-01-09 20:04:47 +0100 | [diff] [blame] | 1219 | |
Peter Zijlstra | 9ed6060 | 2010-06-11 17:36:35 +0200 | [diff] [blame] | 1220 | if (event_type & EVENT_FLEXIBLE) { |
Frederic Weisbecker | 889ff01 | 2010-01-09 20:04:47 +0100 | [diff] [blame] | 1221 | list_for_each_entry(event, &ctx->flexible_groups, group_entry) |
Xiao Guangrong | 8c9ed8e | 2009-09-25 13:51:17 +0800 | [diff] [blame] | 1222 | group_sched_out(event, cpuctx, ctx); |
Peter Zijlstra | 9ed6060 | 2010-06-11 17:36:35 +0200 | [diff] [blame] | 1223 | } |
Peter Zijlstra | 9ed6060 | 2010-06-11 17:36:35 +0200 | [diff] [blame] | 1224 | out: |
Peter Zijlstra | 1b9a644 | 2010-09-07 18:32:22 +0200 | [diff] [blame] | 1225 | perf_pmu_enable(ctx->pmu); |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 1226 | raw_spin_unlock(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1227 | } |
| 1228 | |
| 1229 | /* |
| 1230 | * Test whether two contexts are equivalent, i.e. whether they |
| 1231 | * have both been cloned from the same version of the same context |
| 1232 | * and they both have the same number of enabled events. |
| 1233 | * If the number of enabled events is the same, then the set |
| 1234 | * of enabled events should be the same, because these are both |
| 1235 | * inherited contexts, therefore we can't access individual events |
| 1236 | * in them directly with an fd; we can only enable/disable all |
| 1237 | * events via prctl, or enable/disable all events in a family |
| 1238 | * via ioctl, which will have the same effect on both contexts. |
| 1239 | */ |
| 1240 | static int context_equiv(struct perf_event_context *ctx1, |
| 1241 | struct perf_event_context *ctx2) |
| 1242 | { |
| 1243 | return ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx |
| 1244 | && ctx1->parent_gen == ctx2->parent_gen |
| 1245 | && !ctx1->pin_count && !ctx2->pin_count; |
| 1246 | } |
| 1247 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1248 | static void __perf_event_sync_stat(struct perf_event *event, |
| 1249 | struct perf_event *next_event) |
| 1250 | { |
| 1251 | u64 value; |
| 1252 | |
| 1253 | if (!event->attr.inherit_stat) |
| 1254 | return; |
| 1255 | |
| 1256 | /* |
| 1257 | * Update the event value, we cannot use perf_event_read() |
| 1258 | * because we're in the middle of a context switch and have IRQs |
| 1259 | * disabled, which upsets smp_call_function_single(), however |
| 1260 | * we know the event must be on the current CPU, therefore we |
| 1261 | * don't need to use it. |
| 1262 | */ |
| 1263 | switch (event->state) { |
| 1264 | case PERF_EVENT_STATE_ACTIVE: |
Peter Zijlstra | 3dbebf1 | 2009-11-20 22:19:52 +0100 | [diff] [blame] | 1265 | event->pmu->read(event); |
| 1266 | /* fall-through */ |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1267 | |
| 1268 | case PERF_EVENT_STATE_INACTIVE: |
| 1269 | update_event_times(event); |
| 1270 | break; |
| 1271 | |
| 1272 | default: |
| 1273 | break; |
| 1274 | } |
| 1275 | |
| 1276 | /* |
| 1277 | * In order to keep per-task stats reliable we need to flip the event |
| 1278 | * values when we flip the contexts. |
| 1279 | */ |
Peter Zijlstra | e785059 | 2010-05-21 14:43:08 +0200 | [diff] [blame] | 1280 | value = local64_read(&next_event->count); |
| 1281 | value = local64_xchg(&event->count, value); |
| 1282 | local64_set(&next_event->count, value); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1283 | |
| 1284 | swap(event->total_time_enabled, next_event->total_time_enabled); |
| 1285 | swap(event->total_time_running, next_event->total_time_running); |
| 1286 | |
| 1287 | /* |
| 1288 | * Since we swizzled the values, update the user visible data too. |
| 1289 | */ |
| 1290 | perf_event_update_userpage(event); |
| 1291 | perf_event_update_userpage(next_event); |
| 1292 | } |
| 1293 | |
| 1294 | #define list_next_entry(pos, member) \ |
| 1295 | list_entry(pos->member.next, typeof(*pos), member) |
| 1296 | |
| 1297 | static void perf_event_sync_stat(struct perf_event_context *ctx, |
| 1298 | struct perf_event_context *next_ctx) |
| 1299 | { |
| 1300 | struct perf_event *event, *next_event; |
| 1301 | |
| 1302 | if (!ctx->nr_stat) |
| 1303 | return; |
| 1304 | |
Peter Zijlstra | 02ffdbc | 2009-11-20 22:19:50 +0100 | [diff] [blame] | 1305 | update_context_time(ctx); |
| 1306 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1307 | event = list_first_entry(&ctx->event_list, |
| 1308 | struct perf_event, event_entry); |
| 1309 | |
| 1310 | next_event = list_first_entry(&next_ctx->event_list, |
| 1311 | struct perf_event, event_entry); |
| 1312 | |
| 1313 | while (&event->event_entry != &ctx->event_list && |
| 1314 | &next_event->event_entry != &next_ctx->event_list) { |
| 1315 | |
| 1316 | __perf_event_sync_stat(event, next_event); |
| 1317 | |
| 1318 | event = list_next_entry(event, event_entry); |
| 1319 | next_event = list_next_entry(next_event, event_entry); |
| 1320 | } |
| 1321 | } |
| 1322 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 1323 | void perf_event_context_sched_out(struct task_struct *task, int ctxn, |
| 1324 | struct task_struct *next) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1325 | { |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 1326 | struct perf_event_context *ctx = task->perf_event_ctxp[ctxn]; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1327 | struct perf_event_context *next_ctx; |
| 1328 | struct perf_event_context *parent; |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 1329 | struct perf_cpu_context *cpuctx; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1330 | int do_switch = 1; |
| 1331 | |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 1332 | if (likely(!ctx)) |
| 1333 | return; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1334 | |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 1335 | cpuctx = __get_cpu_context(ctx); |
| 1336 | if (!cpuctx->task_ctx) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1337 | return; |
| 1338 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1339 | rcu_read_lock(); |
| 1340 | parent = rcu_dereference(ctx->parent_ctx); |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 1341 | next_ctx = next->perf_event_ctxp[ctxn]; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1342 | if (parent && next_ctx && |
| 1343 | rcu_dereference(next_ctx->parent_ctx) == parent) { |
| 1344 | /* |
| 1345 | * Looks like the two contexts are clones, so we might be |
| 1346 | * able to optimize the context switch. We lock both |
| 1347 | * contexts and check that they are clones under the |
| 1348 | * lock (including re-checking that neither has been |
| 1349 | * uncloned in the meantime). It doesn't matter which |
| 1350 | * order we take the locks because no other cpu could |
| 1351 | * be trying to lock both of these tasks. |
| 1352 | */ |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 1353 | raw_spin_lock(&ctx->lock); |
| 1354 | raw_spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1355 | if (context_equiv(ctx, next_ctx)) { |
| 1356 | /* |
| 1357 | * XXX do we need a memory barrier of sorts |
| 1358 | * wrt to rcu_dereference() of perf_event_ctxp |
| 1359 | */ |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 1360 | task->perf_event_ctxp[ctxn] = next_ctx; |
| 1361 | next->perf_event_ctxp[ctxn] = ctx; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1362 | ctx->task = next; |
| 1363 | next_ctx->task = task; |
| 1364 | do_switch = 0; |
| 1365 | |
| 1366 | perf_event_sync_stat(ctx, next_ctx); |
| 1367 | } |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 1368 | raw_spin_unlock(&next_ctx->lock); |
| 1369 | raw_spin_unlock(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1370 | } |
| 1371 | rcu_read_unlock(); |
| 1372 | |
| 1373 | if (do_switch) { |
Frederic Weisbecker | 5b0311e | 2010-01-17 11:59:13 +0100 | [diff] [blame] | 1374 | ctx_sched_out(ctx, cpuctx, EVENT_ALL); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1375 | cpuctx->task_ctx = NULL; |
| 1376 | } |
| 1377 | } |
| 1378 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 1379 | #define for_each_task_context_nr(ctxn) \ |
| 1380 | for ((ctxn) = 0; (ctxn) < perf_nr_task_contexts; (ctxn)++) |
| 1381 | |
| 1382 | /* |
| 1383 | * Called from scheduler to remove the events of the current task, |
| 1384 | * with interrupts disabled. |
| 1385 | * |
| 1386 | * We stop each event and update the event value in event->count. |
| 1387 | * |
| 1388 | * This does not protect us against NMI, but disable() |
| 1389 | * sets the disabled bit in the control field of event _before_ |
| 1390 | * accessing the event control register. If a NMI hits, then it will |
| 1391 | * not restart the event. |
| 1392 | */ |
Peter Zijlstra | 82cd6de | 2010-10-14 17:57:23 +0200 | [diff] [blame] | 1393 | void __perf_event_task_sched_out(struct task_struct *task, |
| 1394 | struct task_struct *next) |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 1395 | { |
| 1396 | int ctxn; |
| 1397 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 1398 | for_each_task_context_nr(ctxn) |
| 1399 | perf_event_context_sched_out(task, ctxn, next); |
| 1400 | } |
| 1401 | |
Frederic Weisbecker | 5b0311e | 2010-01-17 11:59:13 +0100 | [diff] [blame] | 1402 | static void task_ctx_sched_out(struct perf_event_context *ctx, |
| 1403 | enum event_type_t event_type) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1404 | { |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 1405 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1406 | |
| 1407 | if (!cpuctx->task_ctx) |
| 1408 | return; |
| 1409 | |
| 1410 | if (WARN_ON_ONCE(ctx != cpuctx->task_ctx)) |
| 1411 | return; |
| 1412 | |
Frederic Weisbecker | 5b0311e | 2010-01-17 11:59:13 +0100 | [diff] [blame] | 1413 | ctx_sched_out(ctx, cpuctx, event_type); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1414 | cpuctx->task_ctx = NULL; |
| 1415 | } |
| 1416 | |
| 1417 | /* |
| 1418 | * Called with IRQs disabled |
| 1419 | */ |
Frederic Weisbecker | 5b0311e | 2010-01-17 11:59:13 +0100 | [diff] [blame] | 1420 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, |
| 1421 | enum event_type_t event_type) |
| 1422 | { |
| 1423 | ctx_sched_out(&cpuctx->ctx, cpuctx, event_type); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1424 | } |
| 1425 | |
| 1426 | static void |
Frederic Weisbecker | 5b0311e | 2010-01-17 11:59:13 +0100 | [diff] [blame] | 1427 | ctx_pinned_sched_in(struct perf_event_context *ctx, |
Peter Zijlstra | 6e37738 | 2010-02-11 13:21:58 +0100 | [diff] [blame] | 1428 | struct perf_cpu_context *cpuctx) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1429 | { |
| 1430 | struct perf_event *event; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1431 | |
Frederic Weisbecker | 889ff01 | 2010-01-09 20:04:47 +0100 | [diff] [blame] | 1432 | list_for_each_entry(event, &ctx->pinned_groups, group_entry) { |
| 1433 | if (event->state <= PERF_EVENT_STATE_OFF) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1434 | continue; |
Peter Zijlstra | 6e37738 | 2010-02-11 13:21:58 +0100 | [diff] [blame] | 1435 | if (event->cpu != -1 && event->cpu != smp_processor_id()) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1436 | continue; |
| 1437 | |
Xiao Guangrong | 8c9ed8e | 2009-09-25 13:51:17 +0800 | [diff] [blame] | 1438 | if (group_can_go_on(event, cpuctx, 1)) |
Peter Zijlstra | 6e37738 | 2010-02-11 13:21:58 +0100 | [diff] [blame] | 1439 | group_sched_in(event, cpuctx, ctx); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1440 | |
| 1441 | /* |
| 1442 | * If this pinned group hasn't been scheduled, |
| 1443 | * put it in error state. |
| 1444 | */ |
| 1445 | if (event->state == PERF_EVENT_STATE_INACTIVE) { |
| 1446 | update_group_times(event); |
| 1447 | event->state = PERF_EVENT_STATE_ERROR; |
| 1448 | } |
| 1449 | } |
Frederic Weisbecker | 5b0311e | 2010-01-17 11:59:13 +0100 | [diff] [blame] | 1450 | } |
| 1451 | |
| 1452 | static void |
| 1453 | ctx_flexible_sched_in(struct perf_event_context *ctx, |
Peter Zijlstra | 6e37738 | 2010-02-11 13:21:58 +0100 | [diff] [blame] | 1454 | struct perf_cpu_context *cpuctx) |
Frederic Weisbecker | 5b0311e | 2010-01-17 11:59:13 +0100 | [diff] [blame] | 1455 | { |
| 1456 | struct perf_event *event; |
| 1457 | int can_add_hw = 1; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1458 | |
Frederic Weisbecker | 889ff01 | 2010-01-09 20:04:47 +0100 | [diff] [blame] | 1459 | list_for_each_entry(event, &ctx->flexible_groups, group_entry) { |
| 1460 | /* Ignore events in OFF or ERROR state */ |
| 1461 | if (event->state <= PERF_EVENT_STATE_OFF) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1462 | continue; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1463 | /* |
| 1464 | * Listen to the 'cpu' scheduling filter constraint |
| 1465 | * of events: |
| 1466 | */ |
Peter Zijlstra | 6e37738 | 2010-02-11 13:21:58 +0100 | [diff] [blame] | 1467 | if (event->cpu != -1 && event->cpu != smp_processor_id()) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1468 | continue; |
| 1469 | |
Peter Zijlstra | 9ed6060 | 2010-06-11 17:36:35 +0200 | [diff] [blame] | 1470 | if (group_can_go_on(event, cpuctx, can_add_hw)) { |
Peter Zijlstra | 6e37738 | 2010-02-11 13:21:58 +0100 | [diff] [blame] | 1471 | if (group_sched_in(event, cpuctx, ctx)) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1472 | can_add_hw = 0; |
Peter Zijlstra | 9ed6060 | 2010-06-11 17:36:35 +0200 | [diff] [blame] | 1473 | } |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1474 | } |
Frederic Weisbecker | 5b0311e | 2010-01-17 11:59:13 +0100 | [diff] [blame] | 1475 | } |
| 1476 | |
| 1477 | static void |
| 1478 | ctx_sched_in(struct perf_event_context *ctx, |
| 1479 | struct perf_cpu_context *cpuctx, |
| 1480 | enum event_type_t event_type) |
| 1481 | { |
Frederic Weisbecker | 5b0311e | 2010-01-17 11:59:13 +0100 | [diff] [blame] | 1482 | raw_spin_lock(&ctx->lock); |
| 1483 | ctx->is_active = 1; |
| 1484 | if (likely(!ctx->nr_events)) |
| 1485 | goto out; |
| 1486 | |
| 1487 | ctx->timestamp = perf_clock(); |
| 1488 | |
Frederic Weisbecker | 5b0311e | 2010-01-17 11:59:13 +0100 | [diff] [blame] | 1489 | /* |
| 1490 | * First go through the list and put on any pinned groups |
| 1491 | * in order to give them the best chance of going on. |
| 1492 | */ |
| 1493 | if (event_type & EVENT_PINNED) |
Peter Zijlstra | 6e37738 | 2010-02-11 13:21:58 +0100 | [diff] [blame] | 1494 | ctx_pinned_sched_in(ctx, cpuctx); |
Frederic Weisbecker | 5b0311e | 2010-01-17 11:59:13 +0100 | [diff] [blame] | 1495 | |
| 1496 | /* Then walk through the lower prio flexible groups */ |
| 1497 | if (event_type & EVENT_FLEXIBLE) |
Peter Zijlstra | 6e37738 | 2010-02-11 13:21:58 +0100 | [diff] [blame] | 1498 | ctx_flexible_sched_in(ctx, cpuctx); |
Frederic Weisbecker | 5b0311e | 2010-01-17 11:59:13 +0100 | [diff] [blame] | 1499 | |
Peter Zijlstra | 9ed6060 | 2010-06-11 17:36:35 +0200 | [diff] [blame] | 1500 | out: |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 1501 | raw_spin_unlock(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1502 | } |
| 1503 | |
Frederic Weisbecker | 329c0e0 | 2010-01-17 12:56:05 +0100 | [diff] [blame] | 1504 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, |
| 1505 | enum event_type_t event_type) |
| 1506 | { |
| 1507 | struct perf_event_context *ctx = &cpuctx->ctx; |
| 1508 | |
| 1509 | ctx_sched_in(ctx, cpuctx, event_type); |
| 1510 | } |
| 1511 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 1512 | static void task_ctx_sched_in(struct perf_event_context *ctx, |
Frederic Weisbecker | 5b0311e | 2010-01-17 11:59:13 +0100 | [diff] [blame] | 1513 | enum event_type_t event_type) |
| 1514 | { |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 1515 | struct perf_cpu_context *cpuctx; |
Frederic Weisbecker | 5b0311e | 2010-01-17 11:59:13 +0100 | [diff] [blame] | 1516 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 1517 | cpuctx = __get_cpu_context(ctx); |
Frederic Weisbecker | 5b0311e | 2010-01-17 11:59:13 +0100 | [diff] [blame] | 1518 | if (cpuctx->task_ctx == ctx) |
| 1519 | return; |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 1520 | |
Frederic Weisbecker | 5b0311e | 2010-01-17 11:59:13 +0100 | [diff] [blame] | 1521 | ctx_sched_in(ctx, cpuctx, event_type); |
| 1522 | cpuctx->task_ctx = ctx; |
| 1523 | } |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1524 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 1525 | void perf_event_context_sched_in(struct perf_event_context *ctx) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1526 | { |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 1527 | struct perf_cpu_context *cpuctx; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1528 | |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 1529 | cpuctx = __get_cpu_context(ctx); |
Frederic Weisbecker | 329c0e0 | 2010-01-17 12:56:05 +0100 | [diff] [blame] | 1530 | if (cpuctx->task_ctx == ctx) |
| 1531 | return; |
| 1532 | |
Peter Zijlstra | 1b9a644 | 2010-09-07 18:32:22 +0200 | [diff] [blame] | 1533 | perf_pmu_disable(ctx->pmu); |
Frederic Weisbecker | 329c0e0 | 2010-01-17 12:56:05 +0100 | [diff] [blame] | 1534 | /* |
| 1535 | * We want to keep the following priority order: |
| 1536 | * cpu pinned (that don't need to move), task pinned, |
| 1537 | * cpu flexible, task flexible. |
| 1538 | */ |
| 1539 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); |
| 1540 | |
| 1541 | ctx_sched_in(ctx, cpuctx, EVENT_PINNED); |
| 1542 | cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE); |
| 1543 | ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE); |
| 1544 | |
| 1545 | cpuctx->task_ctx = ctx; |
eranian@google.com | 9b33fa6 | 2010-03-10 22:26:05 -0800 | [diff] [blame] | 1546 | |
Peter Zijlstra | b5ab4cd | 2010-09-06 16:32:21 +0200 | [diff] [blame] | 1547 | /* |
| 1548 | * Since these rotations are per-cpu, we need to ensure the |
| 1549 | * cpu-context we got scheduled on is actually rotating. |
| 1550 | */ |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 1551 | perf_pmu_rotate_start(ctx->pmu); |
Peter Zijlstra | 1b9a644 | 2010-09-07 18:32:22 +0200 | [diff] [blame] | 1552 | perf_pmu_enable(ctx->pmu); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1553 | } |
| 1554 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 1555 | /* |
| 1556 | * Called from scheduler to add the events of the current task |
| 1557 | * with interrupts disabled. |
| 1558 | * |
| 1559 | * We restore the event value and then enable it. |
| 1560 | * |
| 1561 | * This does not protect us against NMI, but enable() |
| 1562 | * sets the enabled bit in the control field of event _before_ |
| 1563 | * accessing the event control register. If a NMI hits, then it will |
| 1564 | * keep the event running. |
| 1565 | */ |
Peter Zijlstra | 82cd6de | 2010-10-14 17:57:23 +0200 | [diff] [blame] | 1566 | void __perf_event_task_sched_in(struct task_struct *task) |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 1567 | { |
| 1568 | struct perf_event_context *ctx; |
| 1569 | int ctxn; |
| 1570 | |
| 1571 | for_each_task_context_nr(ctxn) { |
| 1572 | ctx = task->perf_event_ctxp[ctxn]; |
| 1573 | if (likely(!ctx)) |
| 1574 | continue; |
| 1575 | |
| 1576 | perf_event_context_sched_in(ctx); |
| 1577 | } |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1578 | } |
| 1579 | |
| 1580 | #define MAX_INTERRUPTS (~0ULL) |
| 1581 | |
| 1582 | static void perf_log_throttle(struct perf_event *event, int enable); |
| 1583 | |
Peter Zijlstra | abd5071 | 2010-01-26 18:50:16 +0100 | [diff] [blame] | 1584 | static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count) |
| 1585 | { |
| 1586 | u64 frequency = event->attr.sample_freq; |
| 1587 | u64 sec = NSEC_PER_SEC; |
| 1588 | u64 divisor, dividend; |
| 1589 | |
| 1590 | int count_fls, nsec_fls, frequency_fls, sec_fls; |
| 1591 | |
| 1592 | count_fls = fls64(count); |
| 1593 | nsec_fls = fls64(nsec); |
| 1594 | frequency_fls = fls64(frequency); |
| 1595 | sec_fls = 30; |
| 1596 | |
| 1597 | /* |
| 1598 | * We got @count in @nsec, with a target of sample_freq HZ |
| 1599 | * the target period becomes: |
| 1600 | * |
| 1601 | * @count * 10^9 |
| 1602 | * period = ------------------- |
| 1603 | * @nsec * sample_freq |
| 1604 | * |
| 1605 | */ |
| 1606 | |
| 1607 | /* |
| 1608 | * Reduce accuracy by one bit such that @a and @b converge |
| 1609 | * to a similar magnitude. |
| 1610 | */ |
| 1611 | #define REDUCE_FLS(a, b) \ |
| 1612 | do { \ |
| 1613 | if (a##_fls > b##_fls) { \ |
| 1614 | a >>= 1; \ |
| 1615 | a##_fls--; \ |
| 1616 | } else { \ |
| 1617 | b >>= 1; \ |
| 1618 | b##_fls--; \ |
| 1619 | } \ |
| 1620 | } while (0) |
| 1621 | |
| 1622 | /* |
| 1623 | * Reduce accuracy until either term fits in a u64, then proceed with |
| 1624 | * the other, so that finally we can do a u64/u64 division. |
| 1625 | */ |
| 1626 | while (count_fls + sec_fls > 64 && nsec_fls + frequency_fls > 64) { |
| 1627 | REDUCE_FLS(nsec, frequency); |
| 1628 | REDUCE_FLS(sec, count); |
| 1629 | } |
| 1630 | |
| 1631 | if (count_fls + sec_fls > 64) { |
| 1632 | divisor = nsec * frequency; |
| 1633 | |
| 1634 | while (count_fls + sec_fls > 64) { |
| 1635 | REDUCE_FLS(count, sec); |
| 1636 | divisor >>= 1; |
| 1637 | } |
| 1638 | |
| 1639 | dividend = count * sec; |
| 1640 | } else { |
| 1641 | dividend = count * sec; |
| 1642 | |
| 1643 | while (nsec_fls + frequency_fls > 64) { |
| 1644 | REDUCE_FLS(nsec, frequency); |
| 1645 | dividend >>= 1; |
| 1646 | } |
| 1647 | |
| 1648 | divisor = nsec * frequency; |
| 1649 | } |
| 1650 | |
Peter Zijlstra | f6ab91a | 2010-06-04 15:18:01 +0200 | [diff] [blame] | 1651 | if (!divisor) |
| 1652 | return dividend; |
| 1653 | |
Peter Zijlstra | abd5071 | 2010-01-26 18:50:16 +0100 | [diff] [blame] | 1654 | return div64_u64(dividend, divisor); |
| 1655 | } |
| 1656 | |
| 1657 | static void perf_adjust_period(struct perf_event *event, u64 nsec, u64 count) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1658 | { |
| 1659 | struct hw_perf_event *hwc = &event->hw; |
Peter Zijlstra | f6ab91a | 2010-06-04 15:18:01 +0200 | [diff] [blame] | 1660 | s64 period, sample_period; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1661 | s64 delta; |
| 1662 | |
Peter Zijlstra | abd5071 | 2010-01-26 18:50:16 +0100 | [diff] [blame] | 1663 | period = perf_calculate_period(event, nsec, count); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1664 | |
| 1665 | delta = (s64)(period - hwc->sample_period); |
| 1666 | delta = (delta + 7) / 8; /* low pass filter */ |
| 1667 | |
| 1668 | sample_period = hwc->sample_period + delta; |
| 1669 | |
| 1670 | if (!sample_period) |
| 1671 | sample_period = 1; |
| 1672 | |
| 1673 | hwc->sample_period = sample_period; |
Peter Zijlstra | abd5071 | 2010-01-26 18:50:16 +0100 | [diff] [blame] | 1674 | |
Peter Zijlstra | e785059 | 2010-05-21 14:43:08 +0200 | [diff] [blame] | 1675 | if (local64_read(&hwc->period_left) > 8*sample_period) { |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 1676 | event->pmu->stop(event, PERF_EF_UPDATE); |
Peter Zijlstra | e785059 | 2010-05-21 14:43:08 +0200 | [diff] [blame] | 1677 | local64_set(&hwc->period_left, 0); |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 1678 | event->pmu->start(event, PERF_EF_RELOAD); |
Peter Zijlstra | abd5071 | 2010-01-26 18:50:16 +0100 | [diff] [blame] | 1679 | } |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1680 | } |
| 1681 | |
Peter Zijlstra | b5ab4cd | 2010-09-06 16:32:21 +0200 | [diff] [blame] | 1682 | static void perf_ctx_adjust_freq(struct perf_event_context *ctx, u64 period) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1683 | { |
| 1684 | struct perf_event *event; |
| 1685 | struct hw_perf_event *hwc; |
Peter Zijlstra | abd5071 | 2010-01-26 18:50:16 +0100 | [diff] [blame] | 1686 | u64 interrupts, now; |
| 1687 | s64 delta; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1688 | |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 1689 | raw_spin_lock(&ctx->lock); |
Paul Mackerras | 03541f8 | 2009-10-14 16:58:03 +1100 | [diff] [blame] | 1690 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1691 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
| 1692 | continue; |
| 1693 | |
Peter Zijlstra | 5d27c23 | 2009-12-17 13:16:32 +0100 | [diff] [blame] | 1694 | if (event->cpu != -1 && event->cpu != smp_processor_id()) |
| 1695 | continue; |
| 1696 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1697 | hwc = &event->hw; |
| 1698 | |
| 1699 | interrupts = hwc->interrupts; |
| 1700 | hwc->interrupts = 0; |
| 1701 | |
| 1702 | /* |
| 1703 | * unthrottle events on the tick |
| 1704 | */ |
| 1705 | if (interrupts == MAX_INTERRUPTS) { |
| 1706 | perf_log_throttle(event, 1); |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 1707 | event->pmu->start(event, 0); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1708 | } |
| 1709 | |
| 1710 | if (!event->attr.freq || !event->attr.sample_freq) |
| 1711 | continue; |
| 1712 | |
Peter Zijlstra | abd5071 | 2010-01-26 18:50:16 +0100 | [diff] [blame] | 1713 | event->pmu->read(event); |
Peter Zijlstra | e785059 | 2010-05-21 14:43:08 +0200 | [diff] [blame] | 1714 | now = local64_read(&event->count); |
Peter Zijlstra | abd5071 | 2010-01-26 18:50:16 +0100 | [diff] [blame] | 1715 | delta = now - hwc->freq_count_stamp; |
| 1716 | hwc->freq_count_stamp = now; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1717 | |
Peter Zijlstra | abd5071 | 2010-01-26 18:50:16 +0100 | [diff] [blame] | 1718 | if (delta > 0) |
Peter Zijlstra | b5ab4cd | 2010-09-06 16:32:21 +0200 | [diff] [blame] | 1719 | perf_adjust_period(event, period, delta); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1720 | } |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 1721 | raw_spin_unlock(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1722 | } |
| 1723 | |
| 1724 | /* |
| 1725 | * Round-robin a context's events: |
| 1726 | */ |
| 1727 | static void rotate_ctx(struct perf_event_context *ctx) |
| 1728 | { |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 1729 | raw_spin_lock(&ctx->lock); |
Frederic Weisbecker | 889ff01 | 2010-01-09 20:04:47 +0100 | [diff] [blame] | 1730 | |
Thomas Gleixner | dddd337 | 2010-11-24 10:05:55 +0100 | [diff] [blame] | 1731 | /* |
| 1732 | * Rotate the first entry last of non-pinned groups. Rotation might be |
| 1733 | * disabled by the inheritance code. |
| 1734 | */ |
| 1735 | if (!ctx->rotate_disable) |
| 1736 | list_rotate_left(&ctx->flexible_groups); |
Frederic Weisbecker | e286417 | 2010-01-09 21:05:28 +0100 | [diff] [blame] | 1737 | |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 1738 | raw_spin_unlock(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1739 | } |
| 1740 | |
Peter Zijlstra | b5ab4cd | 2010-09-06 16:32:21 +0200 | [diff] [blame] | 1741 | /* |
Peter Zijlstra | e9d2b06 | 2010-09-17 11:28:50 +0200 | [diff] [blame] | 1742 | * perf_pmu_rotate_start() and perf_rotate_context() are fully serialized |
| 1743 | * because they're strictly cpu affine and rotate_start is called with IRQs |
| 1744 | * disabled, while rotate_context is called from IRQ context. |
Peter Zijlstra | b5ab4cd | 2010-09-06 16:32:21 +0200 | [diff] [blame] | 1745 | */ |
Peter Zijlstra | e9d2b06 | 2010-09-17 11:28:50 +0200 | [diff] [blame] | 1746 | static void perf_rotate_context(struct perf_cpu_context *cpuctx) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1747 | { |
Peter Zijlstra | e9d2b06 | 2010-09-17 11:28:50 +0200 | [diff] [blame] | 1748 | u64 interval = (u64)cpuctx->jiffies_interval * TICK_NSEC; |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 1749 | struct perf_event_context *ctx = NULL; |
Peter Zijlstra | e9d2b06 | 2010-09-17 11:28:50 +0200 | [diff] [blame] | 1750 | int rotate = 0, remove = 1; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1751 | |
Peter Zijlstra | b5ab4cd | 2010-09-06 16:32:21 +0200 | [diff] [blame] | 1752 | if (cpuctx->ctx.nr_events) { |
Peter Zijlstra | e9d2b06 | 2010-09-17 11:28:50 +0200 | [diff] [blame] | 1753 | remove = 0; |
Peter Zijlstra | b5ab4cd | 2010-09-06 16:32:21 +0200 | [diff] [blame] | 1754 | if (cpuctx->ctx.nr_events != cpuctx->ctx.nr_active) |
| 1755 | rotate = 1; |
| 1756 | } |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1757 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 1758 | ctx = cpuctx->task_ctx; |
Peter Zijlstra | b5ab4cd | 2010-09-06 16:32:21 +0200 | [diff] [blame] | 1759 | if (ctx && ctx->nr_events) { |
Peter Zijlstra | e9d2b06 | 2010-09-17 11:28:50 +0200 | [diff] [blame] | 1760 | remove = 0; |
Peter Zijlstra | b5ab4cd | 2010-09-06 16:32:21 +0200 | [diff] [blame] | 1761 | if (ctx->nr_events != ctx->nr_active) |
| 1762 | rotate = 1; |
| 1763 | } |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1764 | |
Peter Zijlstra | 1b9a644 | 2010-09-07 18:32:22 +0200 | [diff] [blame] | 1765 | perf_pmu_disable(cpuctx->ctx.pmu); |
Peter Zijlstra | e9d2b06 | 2010-09-17 11:28:50 +0200 | [diff] [blame] | 1766 | perf_ctx_adjust_freq(&cpuctx->ctx, interval); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1767 | if (ctx) |
Peter Zijlstra | e9d2b06 | 2010-09-17 11:28:50 +0200 | [diff] [blame] | 1768 | perf_ctx_adjust_freq(ctx, interval); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1769 | |
Peter Zijlstra | d4944a0 | 2010-03-08 13:51:20 +0100 | [diff] [blame] | 1770 | if (!rotate) |
Peter Zijlstra | b5ab4cd | 2010-09-06 16:32:21 +0200 | [diff] [blame] | 1771 | goto done; |
Peter Zijlstra | d4944a0 | 2010-03-08 13:51:20 +0100 | [diff] [blame] | 1772 | |
Frederic Weisbecker | 7defb0f | 2010-01-17 12:15:31 +0100 | [diff] [blame] | 1773 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1774 | if (ctx) |
Frederic Weisbecker | 7defb0f | 2010-01-17 12:15:31 +0100 | [diff] [blame] | 1775 | task_ctx_sched_out(ctx, EVENT_FLEXIBLE); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1776 | |
| 1777 | rotate_ctx(&cpuctx->ctx); |
| 1778 | if (ctx) |
| 1779 | rotate_ctx(ctx); |
| 1780 | |
Frederic Weisbecker | 7defb0f | 2010-01-17 12:15:31 +0100 | [diff] [blame] | 1781 | cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1782 | if (ctx) |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 1783 | task_ctx_sched_in(ctx, EVENT_FLEXIBLE); |
Peter Zijlstra | b5ab4cd | 2010-09-06 16:32:21 +0200 | [diff] [blame] | 1784 | |
| 1785 | done: |
Peter Zijlstra | e9d2b06 | 2010-09-17 11:28:50 +0200 | [diff] [blame] | 1786 | if (remove) |
| 1787 | list_del_init(&cpuctx->rotation_list); |
Peter Zijlstra | b5ab4cd | 2010-09-06 16:32:21 +0200 | [diff] [blame] | 1788 | |
Peter Zijlstra | e9d2b06 | 2010-09-17 11:28:50 +0200 | [diff] [blame] | 1789 | perf_pmu_enable(cpuctx->ctx.pmu); |
| 1790 | } |
| 1791 | |
| 1792 | void perf_event_task_tick(void) |
| 1793 | { |
| 1794 | struct list_head *head = &__get_cpu_var(rotation_list); |
| 1795 | struct perf_cpu_context *cpuctx, *tmp; |
| 1796 | |
| 1797 | WARN_ON(!irqs_disabled()); |
| 1798 | |
| 1799 | list_for_each_entry_safe(cpuctx, tmp, head, rotation_list) { |
| 1800 | if (cpuctx->jiffies_interval == 1 || |
| 1801 | !(jiffies % cpuctx->jiffies_interval)) |
| 1802 | perf_rotate_context(cpuctx); |
| 1803 | } |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1804 | } |
| 1805 | |
Frederic Weisbecker | 889ff01 | 2010-01-09 20:04:47 +0100 | [diff] [blame] | 1806 | static int event_enable_on_exec(struct perf_event *event, |
| 1807 | struct perf_event_context *ctx) |
| 1808 | { |
| 1809 | if (!event->attr.enable_on_exec) |
| 1810 | return 0; |
| 1811 | |
| 1812 | event->attr.enable_on_exec = 0; |
| 1813 | if (event->state >= PERF_EVENT_STATE_INACTIVE) |
| 1814 | return 0; |
| 1815 | |
| 1816 | __perf_event_mark_enabled(event, ctx); |
| 1817 | |
| 1818 | return 1; |
| 1819 | } |
| 1820 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1821 | /* |
| 1822 | * Enable all of a task's events that have been marked enable-on-exec. |
| 1823 | * This expects task == current. |
| 1824 | */ |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 1825 | static void perf_event_enable_on_exec(struct perf_event_context *ctx) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1826 | { |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1827 | struct perf_event *event; |
| 1828 | unsigned long flags; |
| 1829 | int enabled = 0; |
Frederic Weisbecker | 889ff01 | 2010-01-09 20:04:47 +0100 | [diff] [blame] | 1830 | int ret; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1831 | |
| 1832 | local_irq_save(flags); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1833 | if (!ctx || !ctx->nr_events) |
| 1834 | goto out; |
| 1835 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 1836 | task_ctx_sched_out(ctx, EVENT_ALL); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1837 | |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 1838 | raw_spin_lock(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1839 | |
Frederic Weisbecker | 889ff01 | 2010-01-09 20:04:47 +0100 | [diff] [blame] | 1840 | list_for_each_entry(event, &ctx->pinned_groups, group_entry) { |
| 1841 | ret = event_enable_on_exec(event, ctx); |
| 1842 | if (ret) |
| 1843 | enabled = 1; |
| 1844 | } |
| 1845 | |
| 1846 | list_for_each_entry(event, &ctx->flexible_groups, group_entry) { |
| 1847 | ret = event_enable_on_exec(event, ctx); |
| 1848 | if (ret) |
| 1849 | enabled = 1; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1850 | } |
| 1851 | |
| 1852 | /* |
| 1853 | * Unclone this context if we enabled any event. |
| 1854 | */ |
| 1855 | if (enabled) |
| 1856 | unclone_ctx(ctx); |
| 1857 | |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 1858 | raw_spin_unlock(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1859 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 1860 | perf_event_context_sched_in(ctx); |
Peter Zijlstra | 9ed6060 | 2010-06-11 17:36:35 +0200 | [diff] [blame] | 1861 | out: |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1862 | local_irq_restore(flags); |
| 1863 | } |
| 1864 | |
| 1865 | /* |
| 1866 | * Cross CPU call to read the hardware event |
| 1867 | */ |
| 1868 | static void __perf_event_read(void *info) |
| 1869 | { |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1870 | struct perf_event *event = info; |
| 1871 | struct perf_event_context *ctx = event->ctx; |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 1872 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1873 | |
| 1874 | /* |
| 1875 | * If this is a task context, we need to check whether it is |
| 1876 | * the current task context of this cpu. If not it has been |
| 1877 | * scheduled out before the smp call arrived. In that case |
| 1878 | * event->count would have been updated to a recent sample |
| 1879 | * when the event was scheduled out. |
| 1880 | */ |
| 1881 | if (ctx->task && cpuctx->task_ctx != ctx) |
| 1882 | return; |
| 1883 | |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 1884 | raw_spin_lock(&ctx->lock); |
Peter Zijlstra | 58e5ad1 | 2009-11-20 22:19:53 +0100 | [diff] [blame] | 1885 | update_context_time(ctx); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1886 | update_event_times(event); |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 1887 | raw_spin_unlock(&ctx->lock); |
Peter Zijlstra | 2b8988c | 2009-11-20 22:19:54 +0100 | [diff] [blame] | 1888 | |
Peter Zijlstra | 58e5ad1 | 2009-11-20 22:19:53 +0100 | [diff] [blame] | 1889 | event->pmu->read(event); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1890 | } |
| 1891 | |
Peter Zijlstra | b5e5879 | 2010-05-21 14:43:12 +0200 | [diff] [blame] | 1892 | static inline u64 perf_event_count(struct perf_event *event) |
| 1893 | { |
Peter Zijlstra | e785059 | 2010-05-21 14:43:08 +0200 | [diff] [blame] | 1894 | return local64_read(&event->count) + atomic64_read(&event->child_count); |
Peter Zijlstra | b5e5879 | 2010-05-21 14:43:12 +0200 | [diff] [blame] | 1895 | } |
| 1896 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1897 | static u64 perf_event_read(struct perf_event *event) |
| 1898 | { |
| 1899 | /* |
| 1900 | * If event is enabled and currently active on a CPU, update the |
| 1901 | * value in the event structure: |
| 1902 | */ |
| 1903 | if (event->state == PERF_EVENT_STATE_ACTIVE) { |
| 1904 | smp_call_function_single(event->oncpu, |
| 1905 | __perf_event_read, event, 1); |
| 1906 | } else if (event->state == PERF_EVENT_STATE_INACTIVE) { |
Peter Zijlstra | 2b8988c | 2009-11-20 22:19:54 +0100 | [diff] [blame] | 1907 | struct perf_event_context *ctx = event->ctx; |
| 1908 | unsigned long flags; |
| 1909 | |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 1910 | raw_spin_lock_irqsave(&ctx->lock, flags); |
Stephane Eranian | c530ccd | 2010-10-15 15:26:01 +0200 | [diff] [blame] | 1911 | /* |
| 1912 | * may read while context is not active |
| 1913 | * (e.g., thread is blocked), in that case |
| 1914 | * we cannot update context time |
| 1915 | */ |
| 1916 | if (ctx->is_active) |
| 1917 | update_context_time(ctx); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1918 | update_event_times(event); |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 1919 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1920 | } |
| 1921 | |
Peter Zijlstra | b5e5879 | 2010-05-21 14:43:12 +0200 | [diff] [blame] | 1922 | return perf_event_count(event); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 1923 | } |
| 1924 | |
| 1925 | /* |
Frederic Weisbecker | 927c7a9 | 2010-07-01 16:20:36 +0200 | [diff] [blame] | 1926 | * Callchain support |
| 1927 | */ |
| 1928 | |
| 1929 | struct callchain_cpus_entries { |
| 1930 | struct rcu_head rcu_head; |
| 1931 | struct perf_callchain_entry *cpu_entries[0]; |
| 1932 | }; |
| 1933 | |
Frederic Weisbecker | 7ae07ea | 2010-08-14 20:45:13 +0200 | [diff] [blame] | 1934 | static DEFINE_PER_CPU(int, callchain_recursion[PERF_NR_CONTEXTS]); |
Frederic Weisbecker | 927c7a9 | 2010-07-01 16:20:36 +0200 | [diff] [blame] | 1935 | static atomic_t nr_callchain_events; |
| 1936 | static DEFINE_MUTEX(callchain_mutex); |
| 1937 | struct callchain_cpus_entries *callchain_cpus_entries; |
| 1938 | |
| 1939 | |
| 1940 | __weak void perf_callchain_kernel(struct perf_callchain_entry *entry, |
| 1941 | struct pt_regs *regs) |
| 1942 | { |
| 1943 | } |
| 1944 | |
| 1945 | __weak void perf_callchain_user(struct perf_callchain_entry *entry, |
| 1946 | struct pt_regs *regs) |
| 1947 | { |
| 1948 | } |
| 1949 | |
| 1950 | static void release_callchain_buffers_rcu(struct rcu_head *head) |
| 1951 | { |
| 1952 | struct callchain_cpus_entries *entries; |
| 1953 | int cpu; |
| 1954 | |
| 1955 | entries = container_of(head, struct callchain_cpus_entries, rcu_head); |
| 1956 | |
| 1957 | for_each_possible_cpu(cpu) |
| 1958 | kfree(entries->cpu_entries[cpu]); |
| 1959 | |
| 1960 | kfree(entries); |
| 1961 | } |
| 1962 | |
| 1963 | static void release_callchain_buffers(void) |
| 1964 | { |
| 1965 | struct callchain_cpus_entries *entries; |
| 1966 | |
| 1967 | entries = callchain_cpus_entries; |
| 1968 | rcu_assign_pointer(callchain_cpus_entries, NULL); |
| 1969 | call_rcu(&entries->rcu_head, release_callchain_buffers_rcu); |
| 1970 | } |
| 1971 | |
| 1972 | static int alloc_callchain_buffers(void) |
| 1973 | { |
| 1974 | int cpu; |
| 1975 | int size; |
| 1976 | struct callchain_cpus_entries *entries; |
| 1977 | |
| 1978 | /* |
| 1979 | * We can't use the percpu allocation API for data that can be |
| 1980 | * accessed from NMI. Use a temporary manual per cpu allocation |
| 1981 | * until that gets sorted out. |
| 1982 | */ |
| 1983 | size = sizeof(*entries) + sizeof(struct perf_callchain_entry *) * |
| 1984 | num_possible_cpus(); |
| 1985 | |
| 1986 | entries = kzalloc(size, GFP_KERNEL); |
| 1987 | if (!entries) |
| 1988 | return -ENOMEM; |
| 1989 | |
Frederic Weisbecker | 7ae07ea | 2010-08-14 20:45:13 +0200 | [diff] [blame] | 1990 | size = sizeof(struct perf_callchain_entry) * PERF_NR_CONTEXTS; |
Frederic Weisbecker | 927c7a9 | 2010-07-01 16:20:36 +0200 | [diff] [blame] | 1991 | |
| 1992 | for_each_possible_cpu(cpu) { |
| 1993 | entries->cpu_entries[cpu] = kmalloc_node(size, GFP_KERNEL, |
| 1994 | cpu_to_node(cpu)); |
| 1995 | if (!entries->cpu_entries[cpu]) |
| 1996 | goto fail; |
| 1997 | } |
| 1998 | |
| 1999 | rcu_assign_pointer(callchain_cpus_entries, entries); |
| 2000 | |
| 2001 | return 0; |
| 2002 | |
| 2003 | fail: |
| 2004 | for_each_possible_cpu(cpu) |
| 2005 | kfree(entries->cpu_entries[cpu]); |
| 2006 | kfree(entries); |
| 2007 | |
| 2008 | return -ENOMEM; |
| 2009 | } |
| 2010 | |
| 2011 | static int get_callchain_buffers(void) |
| 2012 | { |
| 2013 | int err = 0; |
| 2014 | int count; |
| 2015 | |
| 2016 | mutex_lock(&callchain_mutex); |
| 2017 | |
| 2018 | count = atomic_inc_return(&nr_callchain_events); |
| 2019 | if (WARN_ON_ONCE(count < 1)) { |
| 2020 | err = -EINVAL; |
| 2021 | goto exit; |
| 2022 | } |
| 2023 | |
| 2024 | if (count > 1) { |
| 2025 | /* If the allocation failed, give up */ |
| 2026 | if (!callchain_cpus_entries) |
| 2027 | err = -ENOMEM; |
| 2028 | goto exit; |
| 2029 | } |
| 2030 | |
| 2031 | err = alloc_callchain_buffers(); |
| 2032 | if (err) |
| 2033 | release_callchain_buffers(); |
| 2034 | exit: |
| 2035 | mutex_unlock(&callchain_mutex); |
| 2036 | |
| 2037 | return err; |
| 2038 | } |
| 2039 | |
| 2040 | static void put_callchain_buffers(void) |
| 2041 | { |
| 2042 | if (atomic_dec_and_mutex_lock(&nr_callchain_events, &callchain_mutex)) { |
| 2043 | release_callchain_buffers(); |
| 2044 | mutex_unlock(&callchain_mutex); |
| 2045 | } |
| 2046 | } |
| 2047 | |
| 2048 | static int get_recursion_context(int *recursion) |
| 2049 | { |
| 2050 | int rctx; |
| 2051 | |
| 2052 | if (in_nmi()) |
| 2053 | rctx = 3; |
| 2054 | else if (in_irq()) |
| 2055 | rctx = 2; |
| 2056 | else if (in_softirq()) |
| 2057 | rctx = 1; |
| 2058 | else |
| 2059 | rctx = 0; |
| 2060 | |
| 2061 | if (recursion[rctx]) |
| 2062 | return -1; |
| 2063 | |
| 2064 | recursion[rctx]++; |
| 2065 | barrier(); |
| 2066 | |
| 2067 | return rctx; |
| 2068 | } |
| 2069 | |
| 2070 | static inline void put_recursion_context(int *recursion, int rctx) |
| 2071 | { |
| 2072 | barrier(); |
| 2073 | recursion[rctx]--; |
| 2074 | } |
| 2075 | |
| 2076 | static struct perf_callchain_entry *get_callchain_entry(int *rctx) |
| 2077 | { |
| 2078 | int cpu; |
| 2079 | struct callchain_cpus_entries *entries; |
| 2080 | |
| 2081 | *rctx = get_recursion_context(__get_cpu_var(callchain_recursion)); |
| 2082 | if (*rctx == -1) |
| 2083 | return NULL; |
| 2084 | |
| 2085 | entries = rcu_dereference(callchain_cpus_entries); |
| 2086 | if (!entries) |
| 2087 | return NULL; |
| 2088 | |
| 2089 | cpu = smp_processor_id(); |
| 2090 | |
| 2091 | return &entries->cpu_entries[cpu][*rctx]; |
| 2092 | } |
| 2093 | |
| 2094 | static void |
| 2095 | put_callchain_entry(int rctx) |
| 2096 | { |
| 2097 | put_recursion_context(__get_cpu_var(callchain_recursion), rctx); |
| 2098 | } |
| 2099 | |
| 2100 | static struct perf_callchain_entry *perf_callchain(struct pt_regs *regs) |
| 2101 | { |
| 2102 | int rctx; |
| 2103 | struct perf_callchain_entry *entry; |
| 2104 | |
| 2105 | |
| 2106 | entry = get_callchain_entry(&rctx); |
| 2107 | if (rctx == -1) |
| 2108 | return NULL; |
| 2109 | |
| 2110 | if (!entry) |
| 2111 | goto exit_put; |
| 2112 | |
| 2113 | entry->nr = 0; |
| 2114 | |
| 2115 | if (!user_mode(regs)) { |
| 2116 | perf_callchain_store(entry, PERF_CONTEXT_KERNEL); |
| 2117 | perf_callchain_kernel(entry, regs); |
| 2118 | if (current->mm) |
| 2119 | regs = task_pt_regs(current); |
| 2120 | else |
| 2121 | regs = NULL; |
| 2122 | } |
| 2123 | |
| 2124 | if (regs) { |
| 2125 | perf_callchain_store(entry, PERF_CONTEXT_USER); |
| 2126 | perf_callchain_user(entry, regs); |
| 2127 | } |
| 2128 | |
| 2129 | exit_put: |
| 2130 | put_callchain_entry(rctx); |
| 2131 | |
| 2132 | return entry; |
| 2133 | } |
| 2134 | |
| 2135 | /* |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2136 | * Initialize the perf_event context in a task_struct: |
| 2137 | */ |
Peter Zijlstra | eb18447 | 2010-09-07 15:55:13 +0200 | [diff] [blame] | 2138 | static void __perf_event_init_context(struct perf_event_context *ctx) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2139 | { |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 2140 | raw_spin_lock_init(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2141 | mutex_init(&ctx->mutex); |
Frederic Weisbecker | 889ff01 | 2010-01-09 20:04:47 +0100 | [diff] [blame] | 2142 | INIT_LIST_HEAD(&ctx->pinned_groups); |
| 2143 | INIT_LIST_HEAD(&ctx->flexible_groups); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2144 | INIT_LIST_HEAD(&ctx->event_list); |
| 2145 | atomic_set(&ctx->refcount, 1); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2146 | } |
| 2147 | |
Peter Zijlstra | eb18447 | 2010-09-07 15:55:13 +0200 | [diff] [blame] | 2148 | static struct perf_event_context * |
| 2149 | alloc_perf_context(struct pmu *pmu, struct task_struct *task) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2150 | { |
| 2151 | struct perf_event_context *ctx; |
Peter Zijlstra | eb18447 | 2010-09-07 15:55:13 +0200 | [diff] [blame] | 2152 | |
| 2153 | ctx = kzalloc(sizeof(struct perf_event_context), GFP_KERNEL); |
| 2154 | if (!ctx) |
| 2155 | return NULL; |
| 2156 | |
| 2157 | __perf_event_init_context(ctx); |
| 2158 | if (task) { |
| 2159 | ctx->task = task; |
| 2160 | get_task_struct(task); |
| 2161 | } |
| 2162 | ctx->pmu = pmu; |
| 2163 | |
| 2164 | return ctx; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2165 | } |
| 2166 | |
Matt Helsley | 2ebd4ff | 2010-09-13 13:01:19 -0700 | [diff] [blame] | 2167 | static struct task_struct * |
| 2168 | find_lively_task_by_vpid(pid_t vpid) |
| 2169 | { |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2170 | struct task_struct *task; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2171 | int err; |
| 2172 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2173 | rcu_read_lock(); |
Matt Helsley | 2ebd4ff | 2010-09-13 13:01:19 -0700 | [diff] [blame] | 2174 | if (!vpid) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2175 | task = current; |
| 2176 | else |
Matt Helsley | 2ebd4ff | 2010-09-13 13:01:19 -0700 | [diff] [blame] | 2177 | task = find_task_by_vpid(vpid); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2178 | if (task) |
| 2179 | get_task_struct(task); |
| 2180 | rcu_read_unlock(); |
| 2181 | |
| 2182 | if (!task) |
| 2183 | return ERR_PTR(-ESRCH); |
| 2184 | |
| 2185 | /* |
| 2186 | * Can't attach events to a dying task. |
| 2187 | */ |
| 2188 | err = -ESRCH; |
| 2189 | if (task->flags & PF_EXITING) |
| 2190 | goto errout; |
| 2191 | |
| 2192 | /* Reuse ptrace permission checks for now. */ |
| 2193 | err = -EACCES; |
| 2194 | if (!ptrace_may_access(task, PTRACE_MODE_READ)) |
| 2195 | goto errout; |
| 2196 | |
Matt Helsley | 2ebd4ff | 2010-09-13 13:01:19 -0700 | [diff] [blame] | 2197 | return task; |
| 2198 | errout: |
| 2199 | put_task_struct(task); |
| 2200 | return ERR_PTR(err); |
| 2201 | |
| 2202 | } |
| 2203 | |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 2204 | static struct perf_event_context * |
Matt Helsley | 38a81da | 2010-09-13 13:01:20 -0700 | [diff] [blame] | 2205 | find_get_context(struct pmu *pmu, struct task_struct *task, int cpu) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2206 | { |
| 2207 | struct perf_event_context *ctx; |
| 2208 | struct perf_cpu_context *cpuctx; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2209 | unsigned long flags; |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 2210 | int ctxn, err; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2211 | |
Matt Helsley | 38a81da | 2010-09-13 13:01:20 -0700 | [diff] [blame] | 2212 | if (!task && cpu != -1) { |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2213 | /* Must be root to operate on a CPU event: */ |
| 2214 | if (perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN)) |
| 2215 | return ERR_PTR(-EACCES); |
| 2216 | |
| 2217 | if (cpu < 0 || cpu >= nr_cpumask_bits) |
| 2218 | return ERR_PTR(-EINVAL); |
| 2219 | |
| 2220 | /* |
| 2221 | * We could be clever and allow to attach a event to an |
| 2222 | * offline CPU and activate it when the CPU comes up, but |
| 2223 | * that's for later. |
| 2224 | */ |
| 2225 | if (!cpu_online(cpu)) |
| 2226 | return ERR_PTR(-ENODEV); |
| 2227 | |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 2228 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2229 | ctx = &cpuctx->ctx; |
| 2230 | get_ctx(ctx); |
| 2231 | |
| 2232 | return ctx; |
| 2233 | } |
| 2234 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 2235 | err = -EINVAL; |
| 2236 | ctxn = pmu->task_ctx_nr; |
| 2237 | if (ctxn < 0) |
| 2238 | goto errout; |
| 2239 | |
Peter Zijlstra | 9ed6060 | 2010-06-11 17:36:35 +0200 | [diff] [blame] | 2240 | retry: |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 2241 | ctx = perf_lock_task_context(task, ctxn, &flags); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2242 | if (ctx) { |
| 2243 | unclone_ctx(ctx); |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 2244 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2245 | } |
| 2246 | |
| 2247 | if (!ctx) { |
Peter Zijlstra | eb18447 | 2010-09-07 15:55:13 +0200 | [diff] [blame] | 2248 | ctx = alloc_perf_context(pmu, task); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2249 | err = -ENOMEM; |
| 2250 | if (!ctx) |
| 2251 | goto errout; |
Peter Zijlstra | eb18447 | 2010-09-07 15:55:13 +0200 | [diff] [blame] | 2252 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2253 | get_ctx(ctx); |
Peter Zijlstra | eb18447 | 2010-09-07 15:55:13 +0200 | [diff] [blame] | 2254 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 2255 | if (cmpxchg(&task->perf_event_ctxp[ctxn], NULL, ctx)) { |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2256 | /* |
| 2257 | * We raced with some other task; use |
| 2258 | * the context they set. |
| 2259 | */ |
Peter Zijlstra | eb18447 | 2010-09-07 15:55:13 +0200 | [diff] [blame] | 2260 | put_task_struct(task); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2261 | kfree(ctx); |
| 2262 | goto retry; |
| 2263 | } |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2264 | } |
| 2265 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2266 | return ctx; |
| 2267 | |
Peter Zijlstra | 9ed6060 | 2010-06-11 17:36:35 +0200 | [diff] [blame] | 2268 | errout: |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2269 | return ERR_PTR(err); |
| 2270 | } |
| 2271 | |
Li Zefan | 6fb2915 | 2009-10-15 11:21:42 +0800 | [diff] [blame] | 2272 | static void perf_event_free_filter(struct perf_event *event); |
| 2273 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2274 | static void free_event_rcu(struct rcu_head *head) |
| 2275 | { |
| 2276 | struct perf_event *event; |
| 2277 | |
| 2278 | event = container_of(head, struct perf_event, rcu_head); |
| 2279 | if (event->ns) |
| 2280 | put_pid_ns(event->ns); |
Li Zefan | 6fb2915 | 2009-10-15 11:21:42 +0800 | [diff] [blame] | 2281 | perf_event_free_filter(event); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2282 | kfree(event); |
| 2283 | } |
| 2284 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2285 | static void perf_buffer_put(struct perf_buffer *buffer); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2286 | |
| 2287 | static void free_event(struct perf_event *event) |
| 2288 | { |
Peter Zijlstra | e360adb | 2010-10-14 14:01:34 +0800 | [diff] [blame] | 2289 | irq_work_sync(&event->pending); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2290 | |
| 2291 | if (!event->parent) { |
Peter Zijlstra | 82cd6de | 2010-10-14 17:57:23 +0200 | [diff] [blame] | 2292 | if (event->attach_state & PERF_ATTACH_TASK) |
| 2293 | jump_label_dec(&perf_task_events); |
Eric B Munson | 3af9e85 | 2010-05-18 15:30:49 +0100 | [diff] [blame] | 2294 | if (event->attr.mmap || event->attr.mmap_data) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2295 | atomic_dec(&nr_mmap_events); |
| 2296 | if (event->attr.comm) |
| 2297 | atomic_dec(&nr_comm_events); |
| 2298 | if (event->attr.task) |
| 2299 | atomic_dec(&nr_task_events); |
Frederic Weisbecker | 927c7a9 | 2010-07-01 16:20:36 +0200 | [diff] [blame] | 2300 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) |
| 2301 | put_callchain_buffers(); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2302 | } |
| 2303 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2304 | if (event->buffer) { |
| 2305 | perf_buffer_put(event->buffer); |
| 2306 | event->buffer = NULL; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2307 | } |
| 2308 | |
| 2309 | if (event->destroy) |
| 2310 | event->destroy(event); |
| 2311 | |
Peter Zijlstra | 0c67b40 | 2010-09-13 11:15:58 +0200 | [diff] [blame] | 2312 | if (event->ctx) |
| 2313 | put_ctx(event->ctx); |
| 2314 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2315 | call_rcu(&event->rcu_head, free_event_rcu); |
| 2316 | } |
| 2317 | |
Arjan van de Ven | fb0459d | 2009-09-25 12:25:56 +0200 | [diff] [blame] | 2318 | int perf_event_release_kernel(struct perf_event *event) |
| 2319 | { |
| 2320 | struct perf_event_context *ctx = event->ctx; |
| 2321 | |
Peter Zijlstra | 050735b | 2010-05-11 11:51:53 +0200 | [diff] [blame] | 2322 | /* |
| 2323 | * Remove from the PMU, can't get re-enabled since we got |
| 2324 | * here because the last ref went. |
| 2325 | */ |
| 2326 | perf_event_disable(event); |
| 2327 | |
Arjan van de Ven | fb0459d | 2009-09-25 12:25:56 +0200 | [diff] [blame] | 2328 | WARN_ON_ONCE(ctx->parent_ctx); |
Peter Zijlstra | a0507c8 | 2010-05-06 15:42:53 +0200 | [diff] [blame] | 2329 | /* |
| 2330 | * There are two ways this annotation is useful: |
| 2331 | * |
| 2332 | * 1) there is a lock recursion from perf_event_exit_task |
| 2333 | * see the comment there. |
| 2334 | * |
| 2335 | * 2) there is a lock-inversion with mmap_sem through |
| 2336 | * perf_event_read_group(), which takes faults while |
| 2337 | * holding ctx->mutex, however this is called after |
| 2338 | * the last filedesc died, so there is no possibility |
| 2339 | * to trigger the AB-BA case. |
| 2340 | */ |
| 2341 | mutex_lock_nested(&ctx->mutex, SINGLE_DEPTH_NESTING); |
Peter Zijlstra | 050735b | 2010-05-11 11:51:53 +0200 | [diff] [blame] | 2342 | raw_spin_lock_irq(&ctx->lock); |
Peter Zijlstra | 8a49542 | 2010-05-27 15:47:49 +0200 | [diff] [blame] | 2343 | perf_group_detach(event); |
Peter Zijlstra | 050735b | 2010-05-11 11:51:53 +0200 | [diff] [blame] | 2344 | list_del_event(event, ctx); |
Peter Zijlstra | 050735b | 2010-05-11 11:51:53 +0200 | [diff] [blame] | 2345 | raw_spin_unlock_irq(&ctx->lock); |
Arjan van de Ven | fb0459d | 2009-09-25 12:25:56 +0200 | [diff] [blame] | 2346 | mutex_unlock(&ctx->mutex); |
| 2347 | |
Arjan van de Ven | fb0459d | 2009-09-25 12:25:56 +0200 | [diff] [blame] | 2348 | free_event(event); |
| 2349 | |
| 2350 | return 0; |
| 2351 | } |
| 2352 | EXPORT_SYMBOL_GPL(perf_event_release_kernel); |
| 2353 | |
Peter Zijlstra | a66a305 | 2009-11-23 11:37:23 +0100 | [diff] [blame] | 2354 | /* |
| 2355 | * Called when the last reference to the file is gone. |
| 2356 | */ |
| 2357 | static int perf_release(struct inode *inode, struct file *file) |
| 2358 | { |
| 2359 | struct perf_event *event = file->private_data; |
Peter Zijlstra | 8882135 | 2010-11-09 19:01:43 +0100 | [diff] [blame] | 2360 | struct task_struct *owner; |
Peter Zijlstra | a66a305 | 2009-11-23 11:37:23 +0100 | [diff] [blame] | 2361 | |
| 2362 | file->private_data = NULL; |
| 2363 | |
Peter Zijlstra | 8882135 | 2010-11-09 19:01:43 +0100 | [diff] [blame] | 2364 | rcu_read_lock(); |
| 2365 | owner = ACCESS_ONCE(event->owner); |
| 2366 | /* |
| 2367 | * Matches the smp_wmb() in perf_event_exit_task(). If we observe |
| 2368 | * !owner it means the list deletion is complete and we can indeed |
| 2369 | * free this event, otherwise we need to serialize on |
| 2370 | * owner->perf_event_mutex. |
| 2371 | */ |
| 2372 | smp_read_barrier_depends(); |
| 2373 | if (owner) { |
| 2374 | /* |
| 2375 | * Since delayed_put_task_struct() also drops the last |
| 2376 | * task reference we can safely take a new reference |
| 2377 | * while holding the rcu_read_lock(). |
| 2378 | */ |
| 2379 | get_task_struct(owner); |
| 2380 | } |
| 2381 | rcu_read_unlock(); |
| 2382 | |
| 2383 | if (owner) { |
| 2384 | mutex_lock(&owner->perf_event_mutex); |
| 2385 | /* |
| 2386 | * We have to re-check the event->owner field, if it is cleared |
| 2387 | * we raced with perf_event_exit_task(), acquiring the mutex |
| 2388 | * ensured they're done, and we can proceed with freeing the |
| 2389 | * event. |
| 2390 | */ |
| 2391 | if (event->owner) |
| 2392 | list_del_init(&event->owner_entry); |
| 2393 | mutex_unlock(&owner->perf_event_mutex); |
| 2394 | put_task_struct(owner); |
| 2395 | } |
| 2396 | |
Peter Zijlstra | a66a305 | 2009-11-23 11:37:23 +0100 | [diff] [blame] | 2397 | return perf_event_release_kernel(event); |
| 2398 | } |
| 2399 | |
Peter Zijlstra | 59ed446 | 2009-11-20 22:19:55 +0100 | [diff] [blame] | 2400 | u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2401 | { |
| 2402 | struct perf_event *child; |
| 2403 | u64 total = 0; |
| 2404 | |
Peter Zijlstra | 59ed446 | 2009-11-20 22:19:55 +0100 | [diff] [blame] | 2405 | *enabled = 0; |
| 2406 | *running = 0; |
| 2407 | |
Peter Zijlstra | 6f10581 | 2009-11-20 22:19:56 +0100 | [diff] [blame] | 2408 | mutex_lock(&event->child_mutex); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2409 | total += perf_event_read(event); |
Peter Zijlstra | 59ed446 | 2009-11-20 22:19:55 +0100 | [diff] [blame] | 2410 | *enabled += event->total_time_enabled + |
| 2411 | atomic64_read(&event->child_total_time_enabled); |
| 2412 | *running += event->total_time_running + |
| 2413 | atomic64_read(&event->child_total_time_running); |
| 2414 | |
| 2415 | list_for_each_entry(child, &event->child_list, child_list) { |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2416 | total += perf_event_read(child); |
Peter Zijlstra | 59ed446 | 2009-11-20 22:19:55 +0100 | [diff] [blame] | 2417 | *enabled += child->total_time_enabled; |
| 2418 | *running += child->total_time_running; |
| 2419 | } |
Peter Zijlstra | 6f10581 | 2009-11-20 22:19:56 +0100 | [diff] [blame] | 2420 | mutex_unlock(&event->child_mutex); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2421 | |
| 2422 | return total; |
| 2423 | } |
Arjan van de Ven | fb0459d | 2009-09-25 12:25:56 +0200 | [diff] [blame] | 2424 | EXPORT_SYMBOL_GPL(perf_event_read_value); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2425 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2426 | static int perf_event_read_group(struct perf_event *event, |
| 2427 | u64 read_format, char __user *buf) |
| 2428 | { |
| 2429 | struct perf_event *leader = event->group_leader, *sub; |
Peter Zijlstra | 6f10581 | 2009-11-20 22:19:56 +0100 | [diff] [blame] | 2430 | int n = 0, size = 0, ret = -EFAULT; |
| 2431 | struct perf_event_context *ctx = leader->ctx; |
Peter Zijlstra | abf4868 | 2009-11-20 22:19:49 +0100 | [diff] [blame] | 2432 | u64 values[5]; |
Peter Zijlstra | 59ed446 | 2009-11-20 22:19:55 +0100 | [diff] [blame] | 2433 | u64 count, enabled, running; |
Peter Zijlstra | abf4868 | 2009-11-20 22:19:49 +0100 | [diff] [blame] | 2434 | |
Peter Zijlstra | 6f10581 | 2009-11-20 22:19:56 +0100 | [diff] [blame] | 2435 | mutex_lock(&ctx->mutex); |
Peter Zijlstra | 59ed446 | 2009-11-20 22:19:55 +0100 | [diff] [blame] | 2436 | count = perf_event_read_value(leader, &enabled, &running); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2437 | |
| 2438 | values[n++] = 1 + leader->nr_siblings; |
Peter Zijlstra | 59ed446 | 2009-11-20 22:19:55 +0100 | [diff] [blame] | 2439 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) |
| 2440 | values[n++] = enabled; |
| 2441 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) |
| 2442 | values[n++] = running; |
Peter Zijlstra | abf4868 | 2009-11-20 22:19:49 +0100 | [diff] [blame] | 2443 | values[n++] = count; |
| 2444 | if (read_format & PERF_FORMAT_ID) |
| 2445 | values[n++] = primary_event_id(leader); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2446 | |
| 2447 | size = n * sizeof(u64); |
| 2448 | |
| 2449 | if (copy_to_user(buf, values, size)) |
Peter Zijlstra | 6f10581 | 2009-11-20 22:19:56 +0100 | [diff] [blame] | 2450 | goto unlock; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2451 | |
Peter Zijlstra | 6f10581 | 2009-11-20 22:19:56 +0100 | [diff] [blame] | 2452 | ret = size; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2453 | |
| 2454 | list_for_each_entry(sub, &leader->sibling_list, group_entry) { |
Peter Zijlstra | abf4868 | 2009-11-20 22:19:49 +0100 | [diff] [blame] | 2455 | n = 0; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2456 | |
Peter Zijlstra | 59ed446 | 2009-11-20 22:19:55 +0100 | [diff] [blame] | 2457 | values[n++] = perf_event_read_value(sub, &enabled, &running); |
Peter Zijlstra | abf4868 | 2009-11-20 22:19:49 +0100 | [diff] [blame] | 2458 | if (read_format & PERF_FORMAT_ID) |
| 2459 | values[n++] = primary_event_id(sub); |
| 2460 | |
| 2461 | size = n * sizeof(u64); |
| 2462 | |
Stephane Eranian | 184d3da | 2009-11-23 21:40:49 -0800 | [diff] [blame] | 2463 | if (copy_to_user(buf + ret, values, size)) { |
Peter Zijlstra | 6f10581 | 2009-11-20 22:19:56 +0100 | [diff] [blame] | 2464 | ret = -EFAULT; |
| 2465 | goto unlock; |
| 2466 | } |
Peter Zijlstra | abf4868 | 2009-11-20 22:19:49 +0100 | [diff] [blame] | 2467 | |
| 2468 | ret += size; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2469 | } |
Peter Zijlstra | 6f10581 | 2009-11-20 22:19:56 +0100 | [diff] [blame] | 2470 | unlock: |
| 2471 | mutex_unlock(&ctx->mutex); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2472 | |
Peter Zijlstra | abf4868 | 2009-11-20 22:19:49 +0100 | [diff] [blame] | 2473 | return ret; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2474 | } |
| 2475 | |
| 2476 | static int perf_event_read_one(struct perf_event *event, |
| 2477 | u64 read_format, char __user *buf) |
| 2478 | { |
Peter Zijlstra | 59ed446 | 2009-11-20 22:19:55 +0100 | [diff] [blame] | 2479 | u64 enabled, running; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2480 | u64 values[4]; |
| 2481 | int n = 0; |
| 2482 | |
Peter Zijlstra | 59ed446 | 2009-11-20 22:19:55 +0100 | [diff] [blame] | 2483 | values[n++] = perf_event_read_value(event, &enabled, &running); |
| 2484 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) |
| 2485 | values[n++] = enabled; |
| 2486 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) |
| 2487 | values[n++] = running; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2488 | if (read_format & PERF_FORMAT_ID) |
| 2489 | values[n++] = primary_event_id(event); |
| 2490 | |
| 2491 | if (copy_to_user(buf, values, n * sizeof(u64))) |
| 2492 | return -EFAULT; |
| 2493 | |
| 2494 | return n * sizeof(u64); |
| 2495 | } |
| 2496 | |
| 2497 | /* |
| 2498 | * Read the performance event - simple non blocking version for now |
| 2499 | */ |
| 2500 | static ssize_t |
| 2501 | perf_read_hw(struct perf_event *event, char __user *buf, size_t count) |
| 2502 | { |
| 2503 | u64 read_format = event->attr.read_format; |
| 2504 | int ret; |
| 2505 | |
| 2506 | /* |
| 2507 | * Return end-of-file for a read on a event that is in |
| 2508 | * error state (i.e. because it was pinned but it couldn't be |
| 2509 | * scheduled on to the CPU at some point). |
| 2510 | */ |
| 2511 | if (event->state == PERF_EVENT_STATE_ERROR) |
| 2512 | return 0; |
| 2513 | |
Arnaldo Carvalho de Melo | c320c7b | 2010-10-20 12:50:11 -0200 | [diff] [blame] | 2514 | if (count < event->read_size) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2515 | return -ENOSPC; |
| 2516 | |
| 2517 | WARN_ON_ONCE(event->ctx->parent_ctx); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2518 | if (read_format & PERF_FORMAT_GROUP) |
| 2519 | ret = perf_event_read_group(event, read_format, buf); |
| 2520 | else |
| 2521 | ret = perf_event_read_one(event, read_format, buf); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2522 | |
| 2523 | return ret; |
| 2524 | } |
| 2525 | |
| 2526 | static ssize_t |
| 2527 | perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) |
| 2528 | { |
| 2529 | struct perf_event *event = file->private_data; |
| 2530 | |
| 2531 | return perf_read_hw(event, buf, count); |
| 2532 | } |
| 2533 | |
| 2534 | static unsigned int perf_poll(struct file *file, poll_table *wait) |
| 2535 | { |
| 2536 | struct perf_event *event = file->private_data; |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2537 | struct perf_buffer *buffer; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2538 | unsigned int events = POLL_HUP; |
| 2539 | |
| 2540 | rcu_read_lock(); |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2541 | buffer = rcu_dereference(event->buffer); |
| 2542 | if (buffer) |
| 2543 | events = atomic_xchg(&buffer->poll, 0); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2544 | rcu_read_unlock(); |
| 2545 | |
| 2546 | poll_wait(file, &event->waitq, wait); |
| 2547 | |
| 2548 | return events; |
| 2549 | } |
| 2550 | |
| 2551 | static void perf_event_reset(struct perf_event *event) |
| 2552 | { |
| 2553 | (void)perf_event_read(event); |
Peter Zijlstra | e785059 | 2010-05-21 14:43:08 +0200 | [diff] [blame] | 2554 | local64_set(&event->count, 0); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2555 | perf_event_update_userpage(event); |
| 2556 | } |
| 2557 | |
| 2558 | /* |
| 2559 | * Holding the top-level event's child_mutex means that any |
| 2560 | * descendant process that has inherited this event will block |
| 2561 | * in sync_child_event if it goes to exit, thus satisfying the |
| 2562 | * task existence requirements of perf_event_enable/disable. |
| 2563 | */ |
| 2564 | static void perf_event_for_each_child(struct perf_event *event, |
| 2565 | void (*func)(struct perf_event *)) |
| 2566 | { |
| 2567 | struct perf_event *child; |
| 2568 | |
| 2569 | WARN_ON_ONCE(event->ctx->parent_ctx); |
| 2570 | mutex_lock(&event->child_mutex); |
| 2571 | func(event); |
| 2572 | list_for_each_entry(child, &event->child_list, child_list) |
| 2573 | func(child); |
| 2574 | mutex_unlock(&event->child_mutex); |
| 2575 | } |
| 2576 | |
| 2577 | static void perf_event_for_each(struct perf_event *event, |
| 2578 | void (*func)(struct perf_event *)) |
| 2579 | { |
| 2580 | struct perf_event_context *ctx = event->ctx; |
| 2581 | struct perf_event *sibling; |
| 2582 | |
| 2583 | WARN_ON_ONCE(ctx->parent_ctx); |
| 2584 | mutex_lock(&ctx->mutex); |
| 2585 | event = event->group_leader; |
| 2586 | |
| 2587 | perf_event_for_each_child(event, func); |
| 2588 | func(event); |
| 2589 | list_for_each_entry(sibling, &event->sibling_list, group_entry) |
| 2590 | perf_event_for_each_child(event, func); |
| 2591 | mutex_unlock(&ctx->mutex); |
| 2592 | } |
| 2593 | |
| 2594 | static int perf_event_period(struct perf_event *event, u64 __user *arg) |
| 2595 | { |
| 2596 | struct perf_event_context *ctx = event->ctx; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2597 | int ret = 0; |
| 2598 | u64 value; |
| 2599 | |
Franck Bui-Huu | 6c7e550 | 2010-11-23 16:21:43 +0100 | [diff] [blame] | 2600 | if (!is_sampling_event(event)) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2601 | return -EINVAL; |
| 2602 | |
John Blackwood | ad0cf34 | 2010-09-28 18:03:11 -0400 | [diff] [blame] | 2603 | if (copy_from_user(&value, arg, sizeof(value))) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2604 | return -EFAULT; |
| 2605 | |
| 2606 | if (!value) |
| 2607 | return -EINVAL; |
| 2608 | |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 2609 | raw_spin_lock_irq(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2610 | if (event->attr.freq) { |
| 2611 | if (value > sysctl_perf_event_sample_rate) { |
| 2612 | ret = -EINVAL; |
| 2613 | goto unlock; |
| 2614 | } |
| 2615 | |
| 2616 | event->attr.sample_freq = value; |
| 2617 | } else { |
| 2618 | event->attr.sample_period = value; |
| 2619 | event->hw.sample_period = value; |
| 2620 | } |
| 2621 | unlock: |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 2622 | raw_spin_unlock_irq(&ctx->lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2623 | |
| 2624 | return ret; |
| 2625 | } |
| 2626 | |
Peter Zijlstra | ac9721f | 2010-05-27 12:54:41 +0200 | [diff] [blame] | 2627 | static const struct file_operations perf_fops; |
| 2628 | |
| 2629 | static struct perf_event *perf_fget_light(int fd, int *fput_needed) |
| 2630 | { |
| 2631 | struct file *file; |
| 2632 | |
| 2633 | file = fget_light(fd, fput_needed); |
| 2634 | if (!file) |
| 2635 | return ERR_PTR(-EBADF); |
| 2636 | |
| 2637 | if (file->f_op != &perf_fops) { |
| 2638 | fput_light(file, *fput_needed); |
| 2639 | *fput_needed = 0; |
| 2640 | return ERR_PTR(-EBADF); |
| 2641 | } |
| 2642 | |
| 2643 | return file->private_data; |
| 2644 | } |
| 2645 | |
| 2646 | static int perf_event_set_output(struct perf_event *event, |
| 2647 | struct perf_event *output_event); |
Li Zefan | 6fb2915 | 2009-10-15 11:21:42 +0800 | [diff] [blame] | 2648 | static int perf_event_set_filter(struct perf_event *event, void __user *arg); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2649 | |
| 2650 | static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
| 2651 | { |
| 2652 | struct perf_event *event = file->private_data; |
| 2653 | void (*func)(struct perf_event *); |
| 2654 | u32 flags = arg; |
| 2655 | |
| 2656 | switch (cmd) { |
| 2657 | case PERF_EVENT_IOC_ENABLE: |
| 2658 | func = perf_event_enable; |
| 2659 | break; |
| 2660 | case PERF_EVENT_IOC_DISABLE: |
| 2661 | func = perf_event_disable; |
| 2662 | break; |
| 2663 | case PERF_EVENT_IOC_RESET: |
| 2664 | func = perf_event_reset; |
| 2665 | break; |
| 2666 | |
| 2667 | case PERF_EVENT_IOC_REFRESH: |
| 2668 | return perf_event_refresh(event, arg); |
| 2669 | |
| 2670 | case PERF_EVENT_IOC_PERIOD: |
| 2671 | return perf_event_period(event, (u64 __user *)arg); |
| 2672 | |
| 2673 | case PERF_EVENT_IOC_SET_OUTPUT: |
Peter Zijlstra | ac9721f | 2010-05-27 12:54:41 +0200 | [diff] [blame] | 2674 | { |
| 2675 | struct perf_event *output_event = NULL; |
| 2676 | int fput_needed = 0; |
| 2677 | int ret; |
| 2678 | |
| 2679 | if (arg != -1) { |
| 2680 | output_event = perf_fget_light(arg, &fput_needed); |
| 2681 | if (IS_ERR(output_event)) |
| 2682 | return PTR_ERR(output_event); |
| 2683 | } |
| 2684 | |
| 2685 | ret = perf_event_set_output(event, output_event); |
| 2686 | if (output_event) |
| 2687 | fput_light(output_event->filp, fput_needed); |
| 2688 | |
| 2689 | return ret; |
| 2690 | } |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2691 | |
Li Zefan | 6fb2915 | 2009-10-15 11:21:42 +0800 | [diff] [blame] | 2692 | case PERF_EVENT_IOC_SET_FILTER: |
| 2693 | return perf_event_set_filter(event, (void __user *)arg); |
| 2694 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2695 | default: |
| 2696 | return -ENOTTY; |
| 2697 | } |
| 2698 | |
| 2699 | if (flags & PERF_IOC_FLAG_GROUP) |
| 2700 | perf_event_for_each(event, func); |
| 2701 | else |
| 2702 | perf_event_for_each_child(event, func); |
| 2703 | |
| 2704 | return 0; |
| 2705 | } |
| 2706 | |
| 2707 | int perf_event_task_enable(void) |
| 2708 | { |
| 2709 | struct perf_event *event; |
| 2710 | |
| 2711 | mutex_lock(¤t->perf_event_mutex); |
| 2712 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) |
| 2713 | perf_event_for_each_child(event, perf_event_enable); |
| 2714 | mutex_unlock(¤t->perf_event_mutex); |
| 2715 | |
| 2716 | return 0; |
| 2717 | } |
| 2718 | |
| 2719 | int perf_event_task_disable(void) |
| 2720 | { |
| 2721 | struct perf_event *event; |
| 2722 | |
| 2723 | mutex_lock(¤t->perf_event_mutex); |
| 2724 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) |
| 2725 | perf_event_for_each_child(event, perf_event_disable); |
| 2726 | mutex_unlock(¤t->perf_event_mutex); |
| 2727 | |
| 2728 | return 0; |
| 2729 | } |
| 2730 | |
| 2731 | #ifndef PERF_EVENT_INDEX_OFFSET |
| 2732 | # define PERF_EVENT_INDEX_OFFSET 0 |
| 2733 | #endif |
| 2734 | |
| 2735 | static int perf_event_index(struct perf_event *event) |
| 2736 | { |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 2737 | if (event->hw.state & PERF_HES_STOPPED) |
| 2738 | return 0; |
| 2739 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2740 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
| 2741 | return 0; |
| 2742 | |
| 2743 | return event->hw.idx + 1 - PERF_EVENT_INDEX_OFFSET; |
| 2744 | } |
| 2745 | |
| 2746 | /* |
| 2747 | * Callers need to ensure there can be no nesting of this function, otherwise |
| 2748 | * the seqlock logic goes bad. We can not serialize this because the arch |
| 2749 | * code calls this from NMI context. |
| 2750 | */ |
| 2751 | void perf_event_update_userpage(struct perf_event *event) |
| 2752 | { |
| 2753 | struct perf_event_mmap_page *userpg; |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2754 | struct perf_buffer *buffer; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2755 | |
| 2756 | rcu_read_lock(); |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2757 | buffer = rcu_dereference(event->buffer); |
| 2758 | if (!buffer) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2759 | goto unlock; |
| 2760 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2761 | userpg = buffer->user_page; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2762 | |
| 2763 | /* |
| 2764 | * Disable preemption so as to not let the corresponding user-space |
| 2765 | * spin too long if we get preempted. |
| 2766 | */ |
| 2767 | preempt_disable(); |
| 2768 | ++userpg->lock; |
| 2769 | barrier(); |
| 2770 | userpg->index = perf_event_index(event); |
Peter Zijlstra | b5e5879 | 2010-05-21 14:43:12 +0200 | [diff] [blame] | 2771 | userpg->offset = perf_event_count(event); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2772 | if (event->state == PERF_EVENT_STATE_ACTIVE) |
Peter Zijlstra | e785059 | 2010-05-21 14:43:08 +0200 | [diff] [blame] | 2773 | userpg->offset -= local64_read(&event->hw.prev_count); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2774 | |
| 2775 | userpg->time_enabled = event->total_time_enabled + |
| 2776 | atomic64_read(&event->child_total_time_enabled); |
| 2777 | |
| 2778 | userpg->time_running = event->total_time_running + |
| 2779 | atomic64_read(&event->child_total_time_running); |
| 2780 | |
| 2781 | barrier(); |
| 2782 | ++userpg->lock; |
| 2783 | preempt_enable(); |
| 2784 | unlock: |
| 2785 | rcu_read_unlock(); |
| 2786 | } |
| 2787 | |
Peter Zijlstra | d57e34f | 2010-05-28 19:41:35 +0200 | [diff] [blame] | 2788 | static unsigned long perf_data_size(struct perf_buffer *buffer); |
| 2789 | |
| 2790 | static void |
| 2791 | perf_buffer_init(struct perf_buffer *buffer, long watermark, int flags) |
| 2792 | { |
| 2793 | long max_size = perf_data_size(buffer); |
| 2794 | |
| 2795 | if (watermark) |
| 2796 | buffer->watermark = min(max_size, watermark); |
| 2797 | |
| 2798 | if (!buffer->watermark) |
| 2799 | buffer->watermark = max_size / 2; |
| 2800 | |
| 2801 | if (flags & PERF_BUFFER_WRITABLE) |
| 2802 | buffer->writable = 1; |
| 2803 | |
| 2804 | atomic_set(&buffer->refcount, 1); |
| 2805 | } |
| 2806 | |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 2807 | #ifndef CONFIG_PERF_USE_VMALLOC |
| 2808 | |
| 2809 | /* |
| 2810 | * Back perf_mmap() with regular GFP_KERNEL-0 pages. |
| 2811 | */ |
| 2812 | |
| 2813 | static struct page * |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2814 | perf_mmap_to_page(struct perf_buffer *buffer, unsigned long pgoff) |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 2815 | { |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2816 | if (pgoff > buffer->nr_pages) |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 2817 | return NULL; |
| 2818 | |
| 2819 | if (pgoff == 0) |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2820 | return virt_to_page(buffer->user_page); |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 2821 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2822 | return virt_to_page(buffer->data_pages[pgoff - 1]); |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 2823 | } |
| 2824 | |
Peter Zijlstra | a19d35c | 2010-05-17 18:48:00 +0200 | [diff] [blame] | 2825 | static void *perf_mmap_alloc_page(int cpu) |
| 2826 | { |
| 2827 | struct page *page; |
| 2828 | int node; |
| 2829 | |
| 2830 | node = (cpu == -1) ? cpu : cpu_to_node(cpu); |
| 2831 | page = alloc_pages_node(node, GFP_KERNEL | __GFP_ZERO, 0); |
| 2832 | if (!page) |
| 2833 | return NULL; |
| 2834 | |
| 2835 | return page_address(page); |
| 2836 | } |
| 2837 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2838 | static struct perf_buffer * |
Peter Zijlstra | d57e34f | 2010-05-28 19:41:35 +0200 | [diff] [blame] | 2839 | perf_buffer_alloc(int nr_pages, long watermark, int cpu, int flags) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2840 | { |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2841 | struct perf_buffer *buffer; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2842 | unsigned long size; |
| 2843 | int i; |
| 2844 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2845 | size = sizeof(struct perf_buffer); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2846 | size += nr_pages * sizeof(void *); |
| 2847 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2848 | buffer = kzalloc(size, GFP_KERNEL); |
| 2849 | if (!buffer) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2850 | goto fail; |
| 2851 | |
Peter Zijlstra | d57e34f | 2010-05-28 19:41:35 +0200 | [diff] [blame] | 2852 | buffer->user_page = perf_mmap_alloc_page(cpu); |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2853 | if (!buffer->user_page) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2854 | goto fail_user_page; |
| 2855 | |
| 2856 | for (i = 0; i < nr_pages; i++) { |
Peter Zijlstra | d57e34f | 2010-05-28 19:41:35 +0200 | [diff] [blame] | 2857 | buffer->data_pages[i] = perf_mmap_alloc_page(cpu); |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2858 | if (!buffer->data_pages[i]) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2859 | goto fail_data_pages; |
| 2860 | } |
| 2861 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2862 | buffer->nr_pages = nr_pages; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2863 | |
Peter Zijlstra | d57e34f | 2010-05-28 19:41:35 +0200 | [diff] [blame] | 2864 | perf_buffer_init(buffer, watermark, flags); |
| 2865 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2866 | return buffer; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2867 | |
| 2868 | fail_data_pages: |
| 2869 | for (i--; i >= 0; i--) |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2870 | free_page((unsigned long)buffer->data_pages[i]); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2871 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2872 | free_page((unsigned long)buffer->user_page); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2873 | |
| 2874 | fail_user_page: |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2875 | kfree(buffer); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2876 | |
| 2877 | fail: |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 2878 | return NULL; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2879 | } |
| 2880 | |
| 2881 | static void perf_mmap_free_page(unsigned long addr) |
| 2882 | { |
| 2883 | struct page *page = virt_to_page((void *)addr); |
| 2884 | |
| 2885 | page->mapping = NULL; |
| 2886 | __free_page(page); |
| 2887 | } |
| 2888 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2889 | static void perf_buffer_free(struct perf_buffer *buffer) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2890 | { |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2891 | int i; |
| 2892 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2893 | perf_mmap_free_page((unsigned long)buffer->user_page); |
| 2894 | for (i = 0; i < buffer->nr_pages; i++) |
| 2895 | perf_mmap_free_page((unsigned long)buffer->data_pages[i]); |
| 2896 | kfree(buffer); |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 2897 | } |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 2898 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2899 | static inline int page_order(struct perf_buffer *buffer) |
Peter Zijlstra | 3cafa9f | 2010-05-20 19:07:56 +0200 | [diff] [blame] | 2900 | { |
| 2901 | return 0; |
| 2902 | } |
| 2903 | |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 2904 | #else |
| 2905 | |
| 2906 | /* |
| 2907 | * Back perf_mmap() with vmalloc memory. |
| 2908 | * |
| 2909 | * Required for architectures that have d-cache aliasing issues. |
| 2910 | */ |
| 2911 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2912 | static inline int page_order(struct perf_buffer *buffer) |
Peter Zijlstra | 3cafa9f | 2010-05-20 19:07:56 +0200 | [diff] [blame] | 2913 | { |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2914 | return buffer->page_order; |
Peter Zijlstra | 3cafa9f | 2010-05-20 19:07:56 +0200 | [diff] [blame] | 2915 | } |
| 2916 | |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 2917 | static struct page * |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2918 | perf_mmap_to_page(struct perf_buffer *buffer, unsigned long pgoff) |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 2919 | { |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2920 | if (pgoff > (1UL << page_order(buffer))) |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 2921 | return NULL; |
| 2922 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2923 | return vmalloc_to_page((void *)buffer->user_page + pgoff * PAGE_SIZE); |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 2924 | } |
| 2925 | |
| 2926 | static void perf_mmap_unmark_page(void *addr) |
| 2927 | { |
| 2928 | struct page *page = vmalloc_to_page(addr); |
| 2929 | |
| 2930 | page->mapping = NULL; |
| 2931 | } |
| 2932 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2933 | static void perf_buffer_free_work(struct work_struct *work) |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 2934 | { |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2935 | struct perf_buffer *buffer; |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 2936 | void *base; |
| 2937 | int i, nr; |
| 2938 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2939 | buffer = container_of(work, struct perf_buffer, work); |
| 2940 | nr = 1 << page_order(buffer); |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 2941 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2942 | base = buffer->user_page; |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 2943 | for (i = 0; i < nr + 1; i++) |
| 2944 | perf_mmap_unmark_page(base + (i * PAGE_SIZE)); |
| 2945 | |
| 2946 | vfree(base); |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2947 | kfree(buffer); |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 2948 | } |
| 2949 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2950 | static void perf_buffer_free(struct perf_buffer *buffer) |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 2951 | { |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2952 | schedule_work(&buffer->work); |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 2953 | } |
| 2954 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2955 | static struct perf_buffer * |
Peter Zijlstra | d57e34f | 2010-05-28 19:41:35 +0200 | [diff] [blame] | 2956 | perf_buffer_alloc(int nr_pages, long watermark, int cpu, int flags) |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 2957 | { |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2958 | struct perf_buffer *buffer; |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 2959 | unsigned long size; |
| 2960 | void *all_buf; |
| 2961 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2962 | size = sizeof(struct perf_buffer); |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 2963 | size += sizeof(void *); |
| 2964 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2965 | buffer = kzalloc(size, GFP_KERNEL); |
| 2966 | if (!buffer) |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 2967 | goto fail; |
| 2968 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2969 | INIT_WORK(&buffer->work, perf_buffer_free_work); |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 2970 | |
| 2971 | all_buf = vmalloc_user((nr_pages + 1) * PAGE_SIZE); |
| 2972 | if (!all_buf) |
| 2973 | goto fail_all_buf; |
| 2974 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2975 | buffer->user_page = all_buf; |
| 2976 | buffer->data_pages[0] = all_buf + PAGE_SIZE; |
| 2977 | buffer->page_order = ilog2(nr_pages); |
| 2978 | buffer->nr_pages = 1; |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 2979 | |
Peter Zijlstra | d57e34f | 2010-05-28 19:41:35 +0200 | [diff] [blame] | 2980 | perf_buffer_init(buffer, watermark, flags); |
| 2981 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2982 | return buffer; |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 2983 | |
| 2984 | fail_all_buf: |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2985 | kfree(buffer); |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 2986 | |
| 2987 | fail: |
| 2988 | return NULL; |
| 2989 | } |
| 2990 | |
| 2991 | #endif |
| 2992 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2993 | static unsigned long perf_data_size(struct perf_buffer *buffer) |
Peter Zijlstra | 3cafa9f | 2010-05-20 19:07:56 +0200 | [diff] [blame] | 2994 | { |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 2995 | return buffer->nr_pages << (PAGE_SHIFT + page_order(buffer)); |
Peter Zijlstra | 3cafa9f | 2010-05-20 19:07:56 +0200 | [diff] [blame] | 2996 | } |
| 2997 | |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 2998 | static int perf_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf) |
| 2999 | { |
| 3000 | struct perf_event *event = vma->vm_file->private_data; |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3001 | struct perf_buffer *buffer; |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 3002 | int ret = VM_FAULT_SIGBUS; |
| 3003 | |
| 3004 | if (vmf->flags & FAULT_FLAG_MKWRITE) { |
| 3005 | if (vmf->pgoff == 0) |
| 3006 | ret = 0; |
| 3007 | return ret; |
| 3008 | } |
| 3009 | |
| 3010 | rcu_read_lock(); |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3011 | buffer = rcu_dereference(event->buffer); |
| 3012 | if (!buffer) |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 3013 | goto unlock; |
| 3014 | |
| 3015 | if (vmf->pgoff && (vmf->flags & FAULT_FLAG_WRITE)) |
| 3016 | goto unlock; |
| 3017 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3018 | vmf->page = perf_mmap_to_page(buffer, vmf->pgoff); |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 3019 | if (!vmf->page) |
| 3020 | goto unlock; |
| 3021 | |
| 3022 | get_page(vmf->page); |
| 3023 | vmf->page->mapping = vma->vm_file->f_mapping; |
| 3024 | vmf->page->index = vmf->pgoff; |
| 3025 | |
| 3026 | ret = 0; |
| 3027 | unlock: |
| 3028 | rcu_read_unlock(); |
| 3029 | |
| 3030 | return ret; |
| 3031 | } |
| 3032 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3033 | static void perf_buffer_free_rcu(struct rcu_head *rcu_head) |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 3034 | { |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3035 | struct perf_buffer *buffer; |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 3036 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3037 | buffer = container_of(rcu_head, struct perf_buffer, rcu_head); |
| 3038 | perf_buffer_free(buffer); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3039 | } |
| 3040 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3041 | static struct perf_buffer *perf_buffer_get(struct perf_event *event) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3042 | { |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3043 | struct perf_buffer *buffer; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3044 | |
Peter Zijlstra | ac9721f | 2010-05-27 12:54:41 +0200 | [diff] [blame] | 3045 | rcu_read_lock(); |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3046 | buffer = rcu_dereference(event->buffer); |
| 3047 | if (buffer) { |
| 3048 | if (!atomic_inc_not_zero(&buffer->refcount)) |
| 3049 | buffer = NULL; |
Peter Zijlstra | ac9721f | 2010-05-27 12:54:41 +0200 | [diff] [blame] | 3050 | } |
| 3051 | rcu_read_unlock(); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3052 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3053 | return buffer; |
Peter Zijlstra | ac9721f | 2010-05-27 12:54:41 +0200 | [diff] [blame] | 3054 | } |
| 3055 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3056 | static void perf_buffer_put(struct perf_buffer *buffer) |
Peter Zijlstra | ac9721f | 2010-05-27 12:54:41 +0200 | [diff] [blame] | 3057 | { |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3058 | if (!atomic_dec_and_test(&buffer->refcount)) |
Peter Zijlstra | ac9721f | 2010-05-27 12:54:41 +0200 | [diff] [blame] | 3059 | return; |
| 3060 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3061 | call_rcu(&buffer->rcu_head, perf_buffer_free_rcu); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3062 | } |
| 3063 | |
| 3064 | static void perf_mmap_open(struct vm_area_struct *vma) |
| 3065 | { |
| 3066 | struct perf_event *event = vma->vm_file->private_data; |
| 3067 | |
| 3068 | atomic_inc(&event->mmap_count); |
| 3069 | } |
| 3070 | |
| 3071 | static void perf_mmap_close(struct vm_area_struct *vma) |
| 3072 | { |
| 3073 | struct perf_event *event = vma->vm_file->private_data; |
| 3074 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3075 | if (atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) { |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3076 | unsigned long size = perf_data_size(event->buffer); |
Peter Zijlstra | ac9721f | 2010-05-27 12:54:41 +0200 | [diff] [blame] | 3077 | struct user_struct *user = event->mmap_user; |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3078 | struct perf_buffer *buffer = event->buffer; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3079 | |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 3080 | atomic_long_sub((size >> PAGE_SHIFT) + 1, &user->locked_vm); |
Peter Zijlstra | ac9721f | 2010-05-27 12:54:41 +0200 | [diff] [blame] | 3081 | vma->vm_mm->locked_vm -= event->mmap_locked; |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3082 | rcu_assign_pointer(event->buffer, NULL); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3083 | mutex_unlock(&event->mmap_mutex); |
Peter Zijlstra | ac9721f | 2010-05-27 12:54:41 +0200 | [diff] [blame] | 3084 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3085 | perf_buffer_put(buffer); |
Peter Zijlstra | ac9721f | 2010-05-27 12:54:41 +0200 | [diff] [blame] | 3086 | free_uid(user); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3087 | } |
| 3088 | } |
| 3089 | |
Alexey Dobriyan | f0f37e2 | 2009-09-27 22:29:37 +0400 | [diff] [blame] | 3090 | static const struct vm_operations_struct perf_mmap_vmops = { |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3091 | .open = perf_mmap_open, |
| 3092 | .close = perf_mmap_close, |
| 3093 | .fault = perf_mmap_fault, |
| 3094 | .page_mkwrite = perf_mmap_fault, |
| 3095 | }; |
| 3096 | |
| 3097 | static int perf_mmap(struct file *file, struct vm_area_struct *vma) |
| 3098 | { |
| 3099 | struct perf_event *event = file->private_data; |
| 3100 | unsigned long user_locked, user_lock_limit; |
| 3101 | struct user_struct *user = current_user(); |
| 3102 | unsigned long locked, lock_limit; |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3103 | struct perf_buffer *buffer; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3104 | unsigned long vma_size; |
| 3105 | unsigned long nr_pages; |
| 3106 | long user_extra, extra; |
Peter Zijlstra | d57e34f | 2010-05-28 19:41:35 +0200 | [diff] [blame] | 3107 | int ret = 0, flags = 0; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3108 | |
Peter Zijlstra | c792061 | 2010-05-18 10:33:24 +0200 | [diff] [blame] | 3109 | /* |
| 3110 | * Don't allow mmap() of inherited per-task counters. This would |
| 3111 | * create a performance issue due to all children writing to the |
| 3112 | * same buffer. |
| 3113 | */ |
| 3114 | if (event->cpu == -1 && event->attr.inherit) |
| 3115 | return -EINVAL; |
| 3116 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3117 | if (!(vma->vm_flags & VM_SHARED)) |
| 3118 | return -EINVAL; |
| 3119 | |
| 3120 | vma_size = vma->vm_end - vma->vm_start; |
| 3121 | nr_pages = (vma_size / PAGE_SIZE) - 1; |
| 3122 | |
| 3123 | /* |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3124 | * If we have buffer pages ensure they're a power-of-two number, so we |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3125 | * can do bitmasks instead of modulo. |
| 3126 | */ |
| 3127 | if (nr_pages != 0 && !is_power_of_2(nr_pages)) |
| 3128 | return -EINVAL; |
| 3129 | |
| 3130 | if (vma_size != PAGE_SIZE * (1 + nr_pages)) |
| 3131 | return -EINVAL; |
| 3132 | |
| 3133 | if (vma->vm_pgoff != 0) |
| 3134 | return -EINVAL; |
| 3135 | |
| 3136 | WARN_ON_ONCE(event->ctx->parent_ctx); |
| 3137 | mutex_lock(&event->mmap_mutex); |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3138 | if (event->buffer) { |
| 3139 | if (event->buffer->nr_pages == nr_pages) |
| 3140 | atomic_inc(&event->buffer->refcount); |
Peter Zijlstra | ac9721f | 2010-05-27 12:54:41 +0200 | [diff] [blame] | 3141 | else |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3142 | ret = -EINVAL; |
| 3143 | goto unlock; |
| 3144 | } |
| 3145 | |
| 3146 | user_extra = nr_pages + 1; |
| 3147 | user_lock_limit = sysctl_perf_event_mlock >> (PAGE_SHIFT - 10); |
| 3148 | |
| 3149 | /* |
| 3150 | * Increase the limit linearly with more CPUs: |
| 3151 | */ |
| 3152 | user_lock_limit *= num_online_cpus(); |
| 3153 | |
| 3154 | user_locked = atomic_long_read(&user->locked_vm) + user_extra; |
| 3155 | |
| 3156 | extra = 0; |
| 3157 | if (user_locked > user_lock_limit) |
| 3158 | extra = user_locked - user_lock_limit; |
| 3159 | |
Jiri Slaby | 78d7d40 | 2010-03-05 13:42:54 -0800 | [diff] [blame] | 3160 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3161 | lock_limit >>= PAGE_SHIFT; |
| 3162 | locked = vma->vm_mm->locked_vm + extra; |
| 3163 | |
| 3164 | if ((locked > lock_limit) && perf_paranoid_tracepoint_raw() && |
| 3165 | !capable(CAP_IPC_LOCK)) { |
| 3166 | ret = -EPERM; |
| 3167 | goto unlock; |
| 3168 | } |
| 3169 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3170 | WARN_ON(event->buffer); |
Peter Zijlstra | 906010b | 2009-09-21 16:08:49 +0200 | [diff] [blame] | 3171 | |
Peter Zijlstra | d57e34f | 2010-05-28 19:41:35 +0200 | [diff] [blame] | 3172 | if (vma->vm_flags & VM_WRITE) |
| 3173 | flags |= PERF_BUFFER_WRITABLE; |
| 3174 | |
| 3175 | buffer = perf_buffer_alloc(nr_pages, event->attr.wakeup_watermark, |
| 3176 | event->cpu, flags); |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3177 | if (!buffer) { |
Peter Zijlstra | ac9721f | 2010-05-27 12:54:41 +0200 | [diff] [blame] | 3178 | ret = -ENOMEM; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3179 | goto unlock; |
Peter Zijlstra | ac9721f | 2010-05-27 12:54:41 +0200 | [diff] [blame] | 3180 | } |
Peter Zijlstra | d57e34f | 2010-05-28 19:41:35 +0200 | [diff] [blame] | 3181 | rcu_assign_pointer(event->buffer, buffer); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3182 | |
Peter Zijlstra | ac9721f | 2010-05-27 12:54:41 +0200 | [diff] [blame] | 3183 | atomic_long_add(user_extra, &user->locked_vm); |
| 3184 | event->mmap_locked = extra; |
| 3185 | event->mmap_user = get_current_user(); |
| 3186 | vma->vm_mm->locked_vm += event->mmap_locked; |
| 3187 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3188 | unlock: |
Peter Zijlstra | ac9721f | 2010-05-27 12:54:41 +0200 | [diff] [blame] | 3189 | if (!ret) |
| 3190 | atomic_inc(&event->mmap_count); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3191 | mutex_unlock(&event->mmap_mutex); |
| 3192 | |
| 3193 | vma->vm_flags |= VM_RESERVED; |
| 3194 | vma->vm_ops = &perf_mmap_vmops; |
| 3195 | |
| 3196 | return ret; |
| 3197 | } |
| 3198 | |
| 3199 | static int perf_fasync(int fd, struct file *filp, int on) |
| 3200 | { |
| 3201 | struct inode *inode = filp->f_path.dentry->d_inode; |
| 3202 | struct perf_event *event = filp->private_data; |
| 3203 | int retval; |
| 3204 | |
| 3205 | mutex_lock(&inode->i_mutex); |
| 3206 | retval = fasync_helper(fd, filp, on, &event->fasync); |
| 3207 | mutex_unlock(&inode->i_mutex); |
| 3208 | |
| 3209 | if (retval < 0) |
| 3210 | return retval; |
| 3211 | |
| 3212 | return 0; |
| 3213 | } |
| 3214 | |
| 3215 | static const struct file_operations perf_fops = { |
Arnd Bergmann | 3326c1c | 2010-03-23 19:09:33 +0100 | [diff] [blame] | 3216 | .llseek = no_llseek, |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3217 | .release = perf_release, |
| 3218 | .read = perf_read, |
| 3219 | .poll = perf_poll, |
| 3220 | .unlocked_ioctl = perf_ioctl, |
| 3221 | .compat_ioctl = perf_ioctl, |
| 3222 | .mmap = perf_mmap, |
| 3223 | .fasync = perf_fasync, |
| 3224 | }; |
| 3225 | |
| 3226 | /* |
| 3227 | * Perf event wakeup |
| 3228 | * |
| 3229 | * If there's data, ensure we set the poll() state and publish everything |
| 3230 | * to user-space before waking everybody up. |
| 3231 | */ |
| 3232 | |
| 3233 | void perf_event_wakeup(struct perf_event *event) |
| 3234 | { |
| 3235 | wake_up_all(&event->waitq); |
| 3236 | |
| 3237 | if (event->pending_kill) { |
| 3238 | kill_fasync(&event->fasync, SIGIO, event->pending_kill); |
| 3239 | event->pending_kill = 0; |
| 3240 | } |
| 3241 | } |
| 3242 | |
Peter Zijlstra | e360adb | 2010-10-14 14:01:34 +0800 | [diff] [blame] | 3243 | static void perf_pending_event(struct irq_work *entry) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3244 | { |
| 3245 | struct perf_event *event = container_of(entry, |
| 3246 | struct perf_event, pending); |
| 3247 | |
| 3248 | if (event->pending_disable) { |
| 3249 | event->pending_disable = 0; |
| 3250 | __perf_event_disable(event); |
| 3251 | } |
| 3252 | |
| 3253 | if (event->pending_wakeup) { |
| 3254 | event->pending_wakeup = 0; |
| 3255 | perf_event_wakeup(event); |
| 3256 | } |
| 3257 | } |
| 3258 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3259 | /* |
Zhang, Yanmin | 39447b3 | 2010-04-19 13:32:41 +0800 | [diff] [blame] | 3260 | * We assume there is only KVM supporting the callbacks. |
| 3261 | * Later on, we might change it to a list if there is |
| 3262 | * another virtualization implementation supporting the callbacks. |
| 3263 | */ |
| 3264 | struct perf_guest_info_callbacks *perf_guest_cbs; |
| 3265 | |
| 3266 | int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) |
| 3267 | { |
| 3268 | perf_guest_cbs = cbs; |
| 3269 | return 0; |
| 3270 | } |
| 3271 | EXPORT_SYMBOL_GPL(perf_register_guest_info_callbacks); |
| 3272 | |
| 3273 | int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) |
| 3274 | { |
| 3275 | perf_guest_cbs = NULL; |
| 3276 | return 0; |
| 3277 | } |
| 3278 | EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks); |
| 3279 | |
| 3280 | /* |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3281 | * Output |
| 3282 | */ |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3283 | static bool perf_output_space(struct perf_buffer *buffer, unsigned long tail, |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3284 | unsigned long offset, unsigned long head) |
| 3285 | { |
| 3286 | unsigned long mask; |
| 3287 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3288 | if (!buffer->writable) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3289 | return true; |
| 3290 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3291 | mask = perf_data_size(buffer) - 1; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3292 | |
| 3293 | offset = (offset - tail) & mask; |
| 3294 | head = (head - tail) & mask; |
| 3295 | |
| 3296 | if ((int)(head - offset) < 0) |
| 3297 | return false; |
| 3298 | |
| 3299 | return true; |
| 3300 | } |
| 3301 | |
| 3302 | static void perf_output_wakeup(struct perf_output_handle *handle) |
| 3303 | { |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3304 | atomic_set(&handle->buffer->poll, POLL_IN); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3305 | |
| 3306 | if (handle->nmi) { |
| 3307 | handle->event->pending_wakeup = 1; |
Peter Zijlstra | e360adb | 2010-10-14 14:01:34 +0800 | [diff] [blame] | 3308 | irq_work_queue(&handle->event->pending); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3309 | } else |
| 3310 | perf_event_wakeup(handle->event); |
| 3311 | } |
| 3312 | |
| 3313 | /* |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3314 | * We need to ensure a later event_id doesn't publish a head when a former |
Peter Zijlstra | ef60777 | 2010-05-18 10:50:41 +0200 | [diff] [blame] | 3315 | * event isn't done writing. However since we need to deal with NMIs we |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3316 | * cannot fully serialize things. |
| 3317 | * |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3318 | * We only publish the head (and generate a wakeup) when the outer-most |
Peter Zijlstra | ef60777 | 2010-05-18 10:50:41 +0200 | [diff] [blame] | 3319 | * event completes. |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3320 | */ |
Peter Zijlstra | ef60777 | 2010-05-18 10:50:41 +0200 | [diff] [blame] | 3321 | static void perf_output_get_handle(struct perf_output_handle *handle) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3322 | { |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3323 | struct perf_buffer *buffer = handle->buffer; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3324 | |
Peter Zijlstra | ef60777 | 2010-05-18 10:50:41 +0200 | [diff] [blame] | 3325 | preempt_disable(); |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3326 | local_inc(&buffer->nest); |
| 3327 | handle->wakeup = local_read(&buffer->wakeup); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3328 | } |
| 3329 | |
Peter Zijlstra | ef60777 | 2010-05-18 10:50:41 +0200 | [diff] [blame] | 3330 | static void perf_output_put_handle(struct perf_output_handle *handle) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3331 | { |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3332 | struct perf_buffer *buffer = handle->buffer; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3333 | unsigned long head; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3334 | |
| 3335 | again: |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3336 | head = local_read(&buffer->head); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3337 | |
| 3338 | /* |
Peter Zijlstra | ef60777 | 2010-05-18 10:50:41 +0200 | [diff] [blame] | 3339 | * IRQ/NMI can happen here, which means we can miss a head update. |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3340 | */ |
| 3341 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3342 | if (!local_dec_and_test(&buffer->nest)) |
Frederic Weisbecker | acd35a4 | 2010-05-20 21:28:34 +0200 | [diff] [blame] | 3343 | goto out; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3344 | |
| 3345 | /* |
Peter Zijlstra | ef60777 | 2010-05-18 10:50:41 +0200 | [diff] [blame] | 3346 | * Publish the known good head. Rely on the full barrier implied |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3347 | * by atomic_dec_and_test() order the buffer->head read and this |
Peter Zijlstra | ef60777 | 2010-05-18 10:50:41 +0200 | [diff] [blame] | 3348 | * write. |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3349 | */ |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3350 | buffer->user_page->data_head = head; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3351 | |
Peter Zijlstra | ef60777 | 2010-05-18 10:50:41 +0200 | [diff] [blame] | 3352 | /* |
| 3353 | * Now check if we missed an update, rely on the (compiler) |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3354 | * barrier in atomic_dec_and_test() to re-read buffer->head. |
Peter Zijlstra | ef60777 | 2010-05-18 10:50:41 +0200 | [diff] [blame] | 3355 | */ |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3356 | if (unlikely(head != local_read(&buffer->head))) { |
| 3357 | local_inc(&buffer->nest); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3358 | goto again; |
| 3359 | } |
| 3360 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3361 | if (handle->wakeup != local_read(&buffer->wakeup)) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3362 | perf_output_wakeup(handle); |
Peter Zijlstra | ef60777 | 2010-05-18 10:50:41 +0200 | [diff] [blame] | 3363 | |
Peter Zijlstra | 9ed6060 | 2010-06-11 17:36:35 +0200 | [diff] [blame] | 3364 | out: |
Peter Zijlstra | ef60777 | 2010-05-18 10:50:41 +0200 | [diff] [blame] | 3365 | preempt_enable(); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3366 | } |
| 3367 | |
Peter Zijlstra | a94ffaa | 2010-05-20 19:50:07 +0200 | [diff] [blame] | 3368 | __always_inline void perf_output_copy(struct perf_output_handle *handle, |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3369 | const void *buf, unsigned int len) |
| 3370 | { |
Peter Zijlstra | 5d967a8 | 2010-05-20 16:46:39 +0200 | [diff] [blame] | 3371 | do { |
Peter Zijlstra | a94ffaa | 2010-05-20 19:50:07 +0200 | [diff] [blame] | 3372 | unsigned long size = min_t(unsigned long, handle->size, len); |
Peter Zijlstra | 5d967a8 | 2010-05-20 16:46:39 +0200 | [diff] [blame] | 3373 | |
| 3374 | memcpy(handle->addr, buf, size); |
| 3375 | |
| 3376 | len -= size; |
| 3377 | handle->addr += size; |
Frederic Weisbecker | 74048f8 | 2010-05-27 21:34:58 +0200 | [diff] [blame] | 3378 | buf += size; |
Peter Zijlstra | 5d967a8 | 2010-05-20 16:46:39 +0200 | [diff] [blame] | 3379 | handle->size -= size; |
| 3380 | if (!handle->size) { |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3381 | struct perf_buffer *buffer = handle->buffer; |
Peter Zijlstra | 3cafa9f | 2010-05-20 19:07:56 +0200 | [diff] [blame] | 3382 | |
Peter Zijlstra | 5d967a8 | 2010-05-20 16:46:39 +0200 | [diff] [blame] | 3383 | handle->page++; |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3384 | handle->page &= buffer->nr_pages - 1; |
| 3385 | handle->addr = buffer->data_pages[handle->page]; |
| 3386 | handle->size = PAGE_SIZE << page_order(buffer); |
Peter Zijlstra | 5d967a8 | 2010-05-20 16:46:39 +0200 | [diff] [blame] | 3387 | } |
| 3388 | } while (len); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3389 | } |
| 3390 | |
Arnaldo Carvalho de Melo | 6844c09 | 2010-12-03 16:36:35 -0200 | [diff] [blame^] | 3391 | static void perf_event_header__init_id(struct perf_event_header *header, |
| 3392 | struct perf_sample_data *data, |
| 3393 | struct perf_event *event) |
| 3394 | { |
| 3395 | u64 sample_type = event->attr.sample_type; |
| 3396 | |
| 3397 | data->type = sample_type; |
| 3398 | header->size += event->id_header_size; |
| 3399 | |
| 3400 | if (sample_type & PERF_SAMPLE_TID) { |
| 3401 | /* namespace issues */ |
| 3402 | data->tid_entry.pid = perf_event_pid(event, current); |
| 3403 | data->tid_entry.tid = perf_event_tid(event, current); |
| 3404 | } |
| 3405 | |
| 3406 | if (sample_type & PERF_SAMPLE_TIME) |
| 3407 | data->time = perf_clock(); |
| 3408 | |
| 3409 | if (sample_type & PERF_SAMPLE_ID) |
| 3410 | data->id = primary_event_id(event); |
| 3411 | |
| 3412 | if (sample_type & PERF_SAMPLE_STREAM_ID) |
| 3413 | data->stream_id = event->id; |
| 3414 | |
| 3415 | if (sample_type & PERF_SAMPLE_CPU) { |
| 3416 | data->cpu_entry.cpu = raw_smp_processor_id(); |
| 3417 | data->cpu_entry.reserved = 0; |
| 3418 | } |
| 3419 | } |
| 3420 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3421 | int perf_output_begin(struct perf_output_handle *handle, |
| 3422 | struct perf_event *event, unsigned int size, |
| 3423 | int nmi, int sample) |
| 3424 | { |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3425 | struct perf_buffer *buffer; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3426 | unsigned long tail, offset, head; |
| 3427 | int have_lost; |
| 3428 | struct { |
| 3429 | struct perf_event_header header; |
| 3430 | u64 id; |
| 3431 | u64 lost; |
| 3432 | } lost_event; |
| 3433 | |
| 3434 | rcu_read_lock(); |
| 3435 | /* |
| 3436 | * For inherited events we send all the output towards the parent. |
| 3437 | */ |
| 3438 | if (event->parent) |
| 3439 | event = event->parent; |
| 3440 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3441 | buffer = rcu_dereference(event->buffer); |
| 3442 | if (!buffer) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3443 | goto out; |
| 3444 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3445 | handle->buffer = buffer; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3446 | handle->event = event; |
| 3447 | handle->nmi = nmi; |
| 3448 | handle->sample = sample; |
| 3449 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3450 | if (!buffer->nr_pages) |
Stephane Eranian | 00d1d0b | 2010-05-17 12:46:01 +0200 | [diff] [blame] | 3451 | goto out; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3452 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3453 | have_lost = local_read(&buffer->lost); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3454 | if (have_lost) |
| 3455 | size += sizeof(lost_event); |
| 3456 | |
Peter Zijlstra | ef60777 | 2010-05-18 10:50:41 +0200 | [diff] [blame] | 3457 | perf_output_get_handle(handle); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3458 | |
| 3459 | do { |
| 3460 | /* |
| 3461 | * Userspace could choose to issue a mb() before updating the |
| 3462 | * tail pointer. So that all reads will be completed before the |
| 3463 | * write is issued. |
| 3464 | */ |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3465 | tail = ACCESS_ONCE(buffer->user_page->data_tail); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3466 | smp_rmb(); |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3467 | offset = head = local_read(&buffer->head); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3468 | head += size; |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3469 | if (unlikely(!perf_output_space(buffer, tail, offset, head))) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3470 | goto fail; |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3471 | } while (local_cmpxchg(&buffer->head, offset, head) != offset); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3472 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3473 | if (head - local_read(&buffer->wakeup) > buffer->watermark) |
| 3474 | local_add(buffer->watermark, &buffer->wakeup); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3475 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3476 | handle->page = offset >> (PAGE_SHIFT + page_order(buffer)); |
| 3477 | handle->page &= buffer->nr_pages - 1; |
| 3478 | handle->size = offset & ((PAGE_SIZE << page_order(buffer)) - 1); |
| 3479 | handle->addr = buffer->data_pages[handle->page]; |
Peter Zijlstra | 5d967a8 | 2010-05-20 16:46:39 +0200 | [diff] [blame] | 3480 | handle->addr += handle->size; |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3481 | handle->size = (PAGE_SIZE << page_order(buffer)) - handle->size; |
Peter Zijlstra | 5d967a8 | 2010-05-20 16:46:39 +0200 | [diff] [blame] | 3482 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3483 | if (have_lost) { |
| 3484 | lost_event.header.type = PERF_RECORD_LOST; |
| 3485 | lost_event.header.misc = 0; |
| 3486 | lost_event.header.size = sizeof(lost_event); |
| 3487 | lost_event.id = event->id; |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3488 | lost_event.lost = local_xchg(&buffer->lost, 0); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3489 | |
| 3490 | perf_output_put(handle, lost_event); |
| 3491 | } |
| 3492 | |
| 3493 | return 0; |
| 3494 | |
| 3495 | fail: |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3496 | local_inc(&buffer->lost); |
Peter Zijlstra | ef60777 | 2010-05-18 10:50:41 +0200 | [diff] [blame] | 3497 | perf_output_put_handle(handle); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3498 | out: |
| 3499 | rcu_read_unlock(); |
| 3500 | |
| 3501 | return -ENOSPC; |
| 3502 | } |
| 3503 | |
| 3504 | void perf_output_end(struct perf_output_handle *handle) |
| 3505 | { |
| 3506 | struct perf_event *event = handle->event; |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3507 | struct perf_buffer *buffer = handle->buffer; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3508 | |
| 3509 | int wakeup_events = event->attr.wakeup_events; |
| 3510 | |
| 3511 | if (handle->sample && wakeup_events) { |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3512 | int events = local_inc_return(&buffer->events); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3513 | if (events >= wakeup_events) { |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 3514 | local_sub(wakeup_events, &buffer->events); |
| 3515 | local_inc(&buffer->wakeup); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3516 | } |
| 3517 | } |
| 3518 | |
Peter Zijlstra | ef60777 | 2010-05-18 10:50:41 +0200 | [diff] [blame] | 3519 | perf_output_put_handle(handle); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3520 | rcu_read_unlock(); |
| 3521 | } |
| 3522 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3523 | static void perf_output_read_one(struct perf_output_handle *handle, |
Stephane Eranian | eed0152 | 2010-10-26 16:08:01 +0200 | [diff] [blame] | 3524 | struct perf_event *event, |
| 3525 | u64 enabled, u64 running) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3526 | { |
| 3527 | u64 read_format = event->attr.read_format; |
| 3528 | u64 values[4]; |
| 3529 | int n = 0; |
| 3530 | |
Peter Zijlstra | b5e5879 | 2010-05-21 14:43:12 +0200 | [diff] [blame] | 3531 | values[n++] = perf_event_count(event); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3532 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { |
Stephane Eranian | eed0152 | 2010-10-26 16:08:01 +0200 | [diff] [blame] | 3533 | values[n++] = enabled + |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3534 | atomic64_read(&event->child_total_time_enabled); |
| 3535 | } |
| 3536 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { |
Stephane Eranian | eed0152 | 2010-10-26 16:08:01 +0200 | [diff] [blame] | 3537 | values[n++] = running + |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3538 | atomic64_read(&event->child_total_time_running); |
| 3539 | } |
| 3540 | if (read_format & PERF_FORMAT_ID) |
| 3541 | values[n++] = primary_event_id(event); |
| 3542 | |
| 3543 | perf_output_copy(handle, values, n * sizeof(u64)); |
| 3544 | } |
| 3545 | |
| 3546 | /* |
| 3547 | * XXX PERF_FORMAT_GROUP vs inherited events seems difficult. |
| 3548 | */ |
| 3549 | static void perf_output_read_group(struct perf_output_handle *handle, |
Stephane Eranian | eed0152 | 2010-10-26 16:08:01 +0200 | [diff] [blame] | 3550 | struct perf_event *event, |
| 3551 | u64 enabled, u64 running) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3552 | { |
| 3553 | struct perf_event *leader = event->group_leader, *sub; |
| 3554 | u64 read_format = event->attr.read_format; |
| 3555 | u64 values[5]; |
| 3556 | int n = 0; |
| 3557 | |
| 3558 | values[n++] = 1 + leader->nr_siblings; |
| 3559 | |
| 3560 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) |
Stephane Eranian | eed0152 | 2010-10-26 16:08:01 +0200 | [diff] [blame] | 3561 | values[n++] = enabled; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3562 | |
| 3563 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) |
Stephane Eranian | eed0152 | 2010-10-26 16:08:01 +0200 | [diff] [blame] | 3564 | values[n++] = running; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3565 | |
| 3566 | if (leader != event) |
| 3567 | leader->pmu->read(leader); |
| 3568 | |
Peter Zijlstra | b5e5879 | 2010-05-21 14:43:12 +0200 | [diff] [blame] | 3569 | values[n++] = perf_event_count(leader); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3570 | if (read_format & PERF_FORMAT_ID) |
| 3571 | values[n++] = primary_event_id(leader); |
| 3572 | |
| 3573 | perf_output_copy(handle, values, n * sizeof(u64)); |
| 3574 | |
| 3575 | list_for_each_entry(sub, &leader->sibling_list, group_entry) { |
| 3576 | n = 0; |
| 3577 | |
| 3578 | if (sub != event) |
| 3579 | sub->pmu->read(sub); |
| 3580 | |
Peter Zijlstra | b5e5879 | 2010-05-21 14:43:12 +0200 | [diff] [blame] | 3581 | values[n++] = perf_event_count(sub); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3582 | if (read_format & PERF_FORMAT_ID) |
| 3583 | values[n++] = primary_event_id(sub); |
| 3584 | |
| 3585 | perf_output_copy(handle, values, n * sizeof(u64)); |
| 3586 | } |
| 3587 | } |
| 3588 | |
Stephane Eranian | eed0152 | 2010-10-26 16:08:01 +0200 | [diff] [blame] | 3589 | #define PERF_FORMAT_TOTAL_TIMES (PERF_FORMAT_TOTAL_TIME_ENABLED|\ |
| 3590 | PERF_FORMAT_TOTAL_TIME_RUNNING) |
| 3591 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3592 | static void perf_output_read(struct perf_output_handle *handle, |
| 3593 | struct perf_event *event) |
| 3594 | { |
Stephane Eranian | eed0152 | 2010-10-26 16:08:01 +0200 | [diff] [blame] | 3595 | u64 enabled = 0, running = 0, now, ctx_time; |
| 3596 | u64 read_format = event->attr.read_format; |
| 3597 | |
| 3598 | /* |
| 3599 | * compute total_time_enabled, total_time_running |
| 3600 | * based on snapshot values taken when the event |
| 3601 | * was last scheduled in. |
| 3602 | * |
| 3603 | * we cannot simply called update_context_time() |
| 3604 | * because of locking issue as we are called in |
| 3605 | * NMI context |
| 3606 | */ |
| 3607 | if (read_format & PERF_FORMAT_TOTAL_TIMES) { |
| 3608 | now = perf_clock(); |
| 3609 | ctx_time = event->shadow_ctx_time + now; |
| 3610 | enabled = ctx_time - event->tstamp_enabled; |
| 3611 | running = ctx_time - event->tstamp_running; |
| 3612 | } |
| 3613 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3614 | if (event->attr.read_format & PERF_FORMAT_GROUP) |
Stephane Eranian | eed0152 | 2010-10-26 16:08:01 +0200 | [diff] [blame] | 3615 | perf_output_read_group(handle, event, enabled, running); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3616 | else |
Stephane Eranian | eed0152 | 2010-10-26 16:08:01 +0200 | [diff] [blame] | 3617 | perf_output_read_one(handle, event, enabled, running); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3618 | } |
| 3619 | |
| 3620 | void perf_output_sample(struct perf_output_handle *handle, |
| 3621 | struct perf_event_header *header, |
| 3622 | struct perf_sample_data *data, |
| 3623 | struct perf_event *event) |
| 3624 | { |
| 3625 | u64 sample_type = data->type; |
| 3626 | |
| 3627 | perf_output_put(handle, *header); |
| 3628 | |
| 3629 | if (sample_type & PERF_SAMPLE_IP) |
| 3630 | perf_output_put(handle, data->ip); |
| 3631 | |
| 3632 | if (sample_type & PERF_SAMPLE_TID) |
| 3633 | perf_output_put(handle, data->tid_entry); |
| 3634 | |
| 3635 | if (sample_type & PERF_SAMPLE_TIME) |
| 3636 | perf_output_put(handle, data->time); |
| 3637 | |
| 3638 | if (sample_type & PERF_SAMPLE_ADDR) |
| 3639 | perf_output_put(handle, data->addr); |
| 3640 | |
| 3641 | if (sample_type & PERF_SAMPLE_ID) |
| 3642 | perf_output_put(handle, data->id); |
| 3643 | |
| 3644 | if (sample_type & PERF_SAMPLE_STREAM_ID) |
| 3645 | perf_output_put(handle, data->stream_id); |
| 3646 | |
| 3647 | if (sample_type & PERF_SAMPLE_CPU) |
| 3648 | perf_output_put(handle, data->cpu_entry); |
| 3649 | |
| 3650 | if (sample_type & PERF_SAMPLE_PERIOD) |
| 3651 | perf_output_put(handle, data->period); |
| 3652 | |
| 3653 | if (sample_type & PERF_SAMPLE_READ) |
| 3654 | perf_output_read(handle, event); |
| 3655 | |
| 3656 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { |
| 3657 | if (data->callchain) { |
| 3658 | int size = 1; |
| 3659 | |
| 3660 | if (data->callchain) |
| 3661 | size += data->callchain->nr; |
| 3662 | |
| 3663 | size *= sizeof(u64); |
| 3664 | |
| 3665 | perf_output_copy(handle, data->callchain, size); |
| 3666 | } else { |
| 3667 | u64 nr = 0; |
| 3668 | perf_output_put(handle, nr); |
| 3669 | } |
| 3670 | } |
| 3671 | |
| 3672 | if (sample_type & PERF_SAMPLE_RAW) { |
| 3673 | if (data->raw) { |
| 3674 | perf_output_put(handle, data->raw->size); |
| 3675 | perf_output_copy(handle, data->raw->data, |
| 3676 | data->raw->size); |
| 3677 | } else { |
| 3678 | struct { |
| 3679 | u32 size; |
| 3680 | u32 data; |
| 3681 | } raw = { |
| 3682 | .size = sizeof(u32), |
| 3683 | .data = 0, |
| 3684 | }; |
| 3685 | perf_output_put(handle, raw); |
| 3686 | } |
| 3687 | } |
| 3688 | } |
| 3689 | |
| 3690 | void perf_prepare_sample(struct perf_event_header *header, |
| 3691 | struct perf_sample_data *data, |
| 3692 | struct perf_event *event, |
| 3693 | struct pt_regs *regs) |
| 3694 | { |
| 3695 | u64 sample_type = event->attr.sample_type; |
| 3696 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3697 | header->type = PERF_RECORD_SAMPLE; |
Arnaldo Carvalho de Melo | c320c7b | 2010-10-20 12:50:11 -0200 | [diff] [blame] | 3698 | header->size = sizeof(*header) + event->header_size; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3699 | |
| 3700 | header->misc = 0; |
| 3701 | header->misc |= perf_misc_flags(regs); |
| 3702 | |
Arnaldo Carvalho de Melo | 6844c09 | 2010-12-03 16:36:35 -0200 | [diff] [blame^] | 3703 | perf_event_header__init_id(header, data, event); |
| 3704 | |
Arnaldo Carvalho de Melo | c320c7b | 2010-10-20 12:50:11 -0200 | [diff] [blame] | 3705 | if (sample_type & PERF_SAMPLE_IP) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3706 | data->ip = perf_instruction_pointer(regs); |
| 3707 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3708 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { |
| 3709 | int size = 1; |
| 3710 | |
| 3711 | data->callchain = perf_callchain(regs); |
| 3712 | |
| 3713 | if (data->callchain) |
| 3714 | size += data->callchain->nr; |
| 3715 | |
| 3716 | header->size += size * sizeof(u64); |
| 3717 | } |
| 3718 | |
| 3719 | if (sample_type & PERF_SAMPLE_RAW) { |
| 3720 | int size = sizeof(u32); |
| 3721 | |
| 3722 | if (data->raw) |
| 3723 | size += data->raw->size; |
| 3724 | else |
| 3725 | size += sizeof(u32); |
| 3726 | |
| 3727 | WARN_ON_ONCE(size & (sizeof(u64)-1)); |
| 3728 | header->size += size; |
| 3729 | } |
| 3730 | } |
| 3731 | |
| 3732 | static void perf_event_output(struct perf_event *event, int nmi, |
| 3733 | struct perf_sample_data *data, |
| 3734 | struct pt_regs *regs) |
| 3735 | { |
| 3736 | struct perf_output_handle handle; |
| 3737 | struct perf_event_header header; |
| 3738 | |
Frederic Weisbecker | 927c7a9 | 2010-07-01 16:20:36 +0200 | [diff] [blame] | 3739 | /* protect the callchain buffers */ |
| 3740 | rcu_read_lock(); |
| 3741 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3742 | perf_prepare_sample(&header, data, event, regs); |
| 3743 | |
| 3744 | if (perf_output_begin(&handle, event, header.size, nmi, 1)) |
Frederic Weisbecker | 927c7a9 | 2010-07-01 16:20:36 +0200 | [diff] [blame] | 3745 | goto exit; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3746 | |
| 3747 | perf_output_sample(&handle, &header, data, event); |
| 3748 | |
| 3749 | perf_output_end(&handle); |
Frederic Weisbecker | 927c7a9 | 2010-07-01 16:20:36 +0200 | [diff] [blame] | 3750 | |
| 3751 | exit: |
| 3752 | rcu_read_unlock(); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3753 | } |
| 3754 | |
| 3755 | /* |
| 3756 | * read event_id |
| 3757 | */ |
| 3758 | |
| 3759 | struct perf_read_event { |
| 3760 | struct perf_event_header header; |
| 3761 | |
| 3762 | u32 pid; |
| 3763 | u32 tid; |
| 3764 | }; |
| 3765 | |
| 3766 | static void |
| 3767 | perf_event_read_event(struct perf_event *event, |
| 3768 | struct task_struct *task) |
| 3769 | { |
| 3770 | struct perf_output_handle handle; |
| 3771 | struct perf_read_event read_event = { |
| 3772 | .header = { |
| 3773 | .type = PERF_RECORD_READ, |
| 3774 | .misc = 0, |
Arnaldo Carvalho de Melo | c320c7b | 2010-10-20 12:50:11 -0200 | [diff] [blame] | 3775 | .size = sizeof(read_event) + event->read_size, |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3776 | }, |
| 3777 | .pid = perf_event_pid(event, task), |
| 3778 | .tid = perf_event_tid(event, task), |
| 3779 | }; |
| 3780 | int ret; |
| 3781 | |
| 3782 | ret = perf_output_begin(&handle, event, read_event.header.size, 0, 0); |
| 3783 | if (ret) |
| 3784 | return; |
| 3785 | |
| 3786 | perf_output_put(&handle, read_event); |
| 3787 | perf_output_read(&handle, event); |
| 3788 | |
| 3789 | perf_output_end(&handle); |
| 3790 | } |
| 3791 | |
| 3792 | /* |
| 3793 | * task tracking -- fork/exit |
| 3794 | * |
Eric B Munson | 3af9e85 | 2010-05-18 15:30:49 +0100 | [diff] [blame] | 3795 | * enabled by: attr.comm | attr.mmap | attr.mmap_data | attr.task |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3796 | */ |
| 3797 | |
| 3798 | struct perf_task_event { |
| 3799 | struct task_struct *task; |
| 3800 | struct perf_event_context *task_ctx; |
| 3801 | |
| 3802 | struct { |
| 3803 | struct perf_event_header header; |
| 3804 | |
| 3805 | u32 pid; |
| 3806 | u32 ppid; |
| 3807 | u32 tid; |
| 3808 | u32 ptid; |
| 3809 | u64 time; |
| 3810 | } event_id; |
| 3811 | }; |
| 3812 | |
| 3813 | static void perf_event_task_output(struct perf_event *event, |
| 3814 | struct perf_task_event *task_event) |
| 3815 | { |
| 3816 | struct perf_output_handle handle; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3817 | struct task_struct *task = task_event->task; |
Mike Galbraith | 8bb39f9 | 2010-03-26 11:11:33 +0100 | [diff] [blame] | 3818 | int size, ret; |
| 3819 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3820 | size = task_event->event_id.header.size; |
| 3821 | ret = perf_output_begin(&handle, event, size, 0, 0); |
| 3822 | |
Peter Zijlstra | ef60777 | 2010-05-18 10:50:41 +0200 | [diff] [blame] | 3823 | if (ret) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3824 | return; |
| 3825 | |
| 3826 | task_event->event_id.pid = perf_event_pid(event, task); |
| 3827 | task_event->event_id.ppid = perf_event_pid(event, current); |
| 3828 | |
| 3829 | task_event->event_id.tid = perf_event_tid(event, task); |
| 3830 | task_event->event_id.ptid = perf_event_tid(event, current); |
| 3831 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3832 | perf_output_put(&handle, task_event->event_id); |
| 3833 | |
| 3834 | perf_output_end(&handle); |
| 3835 | } |
| 3836 | |
| 3837 | static int perf_event_task_match(struct perf_event *event) |
| 3838 | { |
Peter Zijlstra | 6f93d0a | 2010-02-14 11:12:04 +0100 | [diff] [blame] | 3839 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
Peter Zijlstra | 22e1908 | 2010-01-18 09:12:32 +0100 | [diff] [blame] | 3840 | return 0; |
| 3841 | |
Peter Zijlstra | 5d27c23 | 2009-12-17 13:16:32 +0100 | [diff] [blame] | 3842 | if (event->cpu != -1 && event->cpu != smp_processor_id()) |
| 3843 | return 0; |
| 3844 | |
Eric B Munson | 3af9e85 | 2010-05-18 15:30:49 +0100 | [diff] [blame] | 3845 | if (event->attr.comm || event->attr.mmap || |
| 3846 | event->attr.mmap_data || event->attr.task) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3847 | return 1; |
| 3848 | |
| 3849 | return 0; |
| 3850 | } |
| 3851 | |
| 3852 | static void perf_event_task_ctx(struct perf_event_context *ctx, |
| 3853 | struct perf_task_event *task_event) |
| 3854 | { |
| 3855 | struct perf_event *event; |
| 3856 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3857 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { |
| 3858 | if (perf_event_task_match(event)) |
| 3859 | perf_event_task_output(event, task_event); |
| 3860 | } |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3861 | } |
| 3862 | |
| 3863 | static void perf_event_task_event(struct perf_task_event *task_event) |
| 3864 | { |
| 3865 | struct perf_cpu_context *cpuctx; |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 3866 | struct perf_event_context *ctx; |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 3867 | struct pmu *pmu; |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 3868 | int ctxn; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3869 | |
Peter Zijlstra | d6ff86c | 2009-11-20 22:19:46 +0100 | [diff] [blame] | 3870 | rcu_read_lock(); |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 3871 | list_for_each_entry_rcu(pmu, &pmus, entry) { |
Peter Zijlstra | 41945f6 | 2010-09-16 19:17:24 +0200 | [diff] [blame] | 3872 | cpuctx = get_cpu_ptr(pmu->pmu_cpu_context); |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 3873 | perf_event_task_ctx(&cpuctx->ctx, task_event); |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 3874 | |
| 3875 | ctx = task_event->task_ctx; |
| 3876 | if (!ctx) { |
| 3877 | ctxn = pmu->task_ctx_nr; |
| 3878 | if (ctxn < 0) |
Peter Zijlstra | 41945f6 | 2010-09-16 19:17:24 +0200 | [diff] [blame] | 3879 | goto next; |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 3880 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); |
| 3881 | } |
| 3882 | if (ctx) |
| 3883 | perf_event_task_ctx(ctx, task_event); |
Peter Zijlstra | 41945f6 | 2010-09-16 19:17:24 +0200 | [diff] [blame] | 3884 | next: |
| 3885 | put_cpu_ptr(pmu->pmu_cpu_context); |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 3886 | } |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3887 | rcu_read_unlock(); |
| 3888 | } |
| 3889 | |
| 3890 | static void perf_event_task(struct task_struct *task, |
| 3891 | struct perf_event_context *task_ctx, |
| 3892 | int new) |
| 3893 | { |
| 3894 | struct perf_task_event task_event; |
| 3895 | |
| 3896 | if (!atomic_read(&nr_comm_events) && |
| 3897 | !atomic_read(&nr_mmap_events) && |
| 3898 | !atomic_read(&nr_task_events)) |
| 3899 | return; |
| 3900 | |
| 3901 | task_event = (struct perf_task_event){ |
| 3902 | .task = task, |
| 3903 | .task_ctx = task_ctx, |
| 3904 | .event_id = { |
| 3905 | .header = { |
| 3906 | .type = new ? PERF_RECORD_FORK : PERF_RECORD_EXIT, |
| 3907 | .misc = 0, |
| 3908 | .size = sizeof(task_event.event_id), |
| 3909 | }, |
| 3910 | /* .pid */ |
| 3911 | /* .ppid */ |
| 3912 | /* .tid */ |
| 3913 | /* .ptid */ |
Peter Zijlstra | 6f93d0a | 2010-02-14 11:12:04 +0100 | [diff] [blame] | 3914 | .time = perf_clock(), |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3915 | }, |
| 3916 | }; |
| 3917 | |
| 3918 | perf_event_task_event(&task_event); |
| 3919 | } |
| 3920 | |
| 3921 | void perf_event_fork(struct task_struct *task) |
| 3922 | { |
| 3923 | perf_event_task(task, NULL, 1); |
| 3924 | } |
| 3925 | |
| 3926 | /* |
| 3927 | * comm tracking |
| 3928 | */ |
| 3929 | |
| 3930 | struct perf_comm_event { |
| 3931 | struct task_struct *task; |
| 3932 | char *comm; |
| 3933 | int comm_size; |
| 3934 | |
| 3935 | struct { |
| 3936 | struct perf_event_header header; |
| 3937 | |
| 3938 | u32 pid; |
| 3939 | u32 tid; |
| 3940 | } event_id; |
| 3941 | }; |
| 3942 | |
| 3943 | static void perf_event_comm_output(struct perf_event *event, |
| 3944 | struct perf_comm_event *comm_event) |
| 3945 | { |
| 3946 | struct perf_output_handle handle; |
| 3947 | int size = comm_event->event_id.header.size; |
| 3948 | int ret = perf_output_begin(&handle, event, size, 0, 0); |
| 3949 | |
| 3950 | if (ret) |
| 3951 | return; |
| 3952 | |
| 3953 | comm_event->event_id.pid = perf_event_pid(event, comm_event->task); |
| 3954 | comm_event->event_id.tid = perf_event_tid(event, comm_event->task); |
| 3955 | |
| 3956 | perf_output_put(&handle, comm_event->event_id); |
| 3957 | perf_output_copy(&handle, comm_event->comm, |
| 3958 | comm_event->comm_size); |
| 3959 | perf_output_end(&handle); |
| 3960 | } |
| 3961 | |
| 3962 | static int perf_event_comm_match(struct perf_event *event) |
| 3963 | { |
Peter Zijlstra | 6f93d0a | 2010-02-14 11:12:04 +0100 | [diff] [blame] | 3964 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
Peter Zijlstra | 22e1908 | 2010-01-18 09:12:32 +0100 | [diff] [blame] | 3965 | return 0; |
| 3966 | |
Peter Zijlstra | 5d27c23 | 2009-12-17 13:16:32 +0100 | [diff] [blame] | 3967 | if (event->cpu != -1 && event->cpu != smp_processor_id()) |
| 3968 | return 0; |
| 3969 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3970 | if (event->attr.comm) |
| 3971 | return 1; |
| 3972 | |
| 3973 | return 0; |
| 3974 | } |
| 3975 | |
| 3976 | static void perf_event_comm_ctx(struct perf_event_context *ctx, |
| 3977 | struct perf_comm_event *comm_event) |
| 3978 | { |
| 3979 | struct perf_event *event; |
| 3980 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3981 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { |
| 3982 | if (perf_event_comm_match(event)) |
| 3983 | perf_event_comm_output(event, comm_event); |
| 3984 | } |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3985 | } |
| 3986 | |
| 3987 | static void perf_event_comm_event(struct perf_comm_event *comm_event) |
| 3988 | { |
| 3989 | struct perf_cpu_context *cpuctx; |
| 3990 | struct perf_event_context *ctx; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3991 | char comm[TASK_COMM_LEN]; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3992 | unsigned int size; |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 3993 | struct pmu *pmu; |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 3994 | int ctxn; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3995 | |
| 3996 | memset(comm, 0, sizeof(comm)); |
Márton Németh | 96b02d7 | 2009-11-21 23:10:15 +0100 | [diff] [blame] | 3997 | strlcpy(comm, comm_event->task->comm, sizeof(comm)); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 3998 | size = ALIGN(strlen(comm)+1, sizeof(u64)); |
| 3999 | |
| 4000 | comm_event->comm = comm; |
| 4001 | comm_event->comm_size = size; |
| 4002 | |
| 4003 | comm_event->event_id.header.size = sizeof(comm_event->event_id) + size; |
| 4004 | |
Peter Zijlstra | f6595f3 | 2009-11-20 22:19:47 +0100 | [diff] [blame] | 4005 | rcu_read_lock(); |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 4006 | list_for_each_entry_rcu(pmu, &pmus, entry) { |
Peter Zijlstra | 41945f6 | 2010-09-16 19:17:24 +0200 | [diff] [blame] | 4007 | cpuctx = get_cpu_ptr(pmu->pmu_cpu_context); |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 4008 | perf_event_comm_ctx(&cpuctx->ctx, comm_event); |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 4009 | |
| 4010 | ctxn = pmu->task_ctx_nr; |
| 4011 | if (ctxn < 0) |
Peter Zijlstra | 41945f6 | 2010-09-16 19:17:24 +0200 | [diff] [blame] | 4012 | goto next; |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 4013 | |
| 4014 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); |
| 4015 | if (ctx) |
| 4016 | perf_event_comm_ctx(ctx, comm_event); |
Peter Zijlstra | 41945f6 | 2010-09-16 19:17:24 +0200 | [diff] [blame] | 4017 | next: |
| 4018 | put_cpu_ptr(pmu->pmu_cpu_context); |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 4019 | } |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4020 | rcu_read_unlock(); |
| 4021 | } |
| 4022 | |
| 4023 | void perf_event_comm(struct task_struct *task) |
| 4024 | { |
| 4025 | struct perf_comm_event comm_event; |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 4026 | struct perf_event_context *ctx; |
| 4027 | int ctxn; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4028 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 4029 | for_each_task_context_nr(ctxn) { |
| 4030 | ctx = task->perf_event_ctxp[ctxn]; |
| 4031 | if (!ctx) |
| 4032 | continue; |
| 4033 | |
| 4034 | perf_event_enable_on_exec(ctx); |
| 4035 | } |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4036 | |
| 4037 | if (!atomic_read(&nr_comm_events)) |
| 4038 | return; |
| 4039 | |
| 4040 | comm_event = (struct perf_comm_event){ |
| 4041 | .task = task, |
| 4042 | /* .comm */ |
| 4043 | /* .comm_size */ |
| 4044 | .event_id = { |
| 4045 | .header = { |
| 4046 | .type = PERF_RECORD_COMM, |
| 4047 | .misc = 0, |
| 4048 | /* .size */ |
| 4049 | }, |
| 4050 | /* .pid */ |
| 4051 | /* .tid */ |
| 4052 | }, |
| 4053 | }; |
| 4054 | |
| 4055 | perf_event_comm_event(&comm_event); |
| 4056 | } |
| 4057 | |
| 4058 | /* |
| 4059 | * mmap tracking |
| 4060 | */ |
| 4061 | |
| 4062 | struct perf_mmap_event { |
| 4063 | struct vm_area_struct *vma; |
| 4064 | |
| 4065 | const char *file_name; |
| 4066 | int file_size; |
| 4067 | |
| 4068 | struct { |
| 4069 | struct perf_event_header header; |
| 4070 | |
| 4071 | u32 pid; |
| 4072 | u32 tid; |
| 4073 | u64 start; |
| 4074 | u64 len; |
| 4075 | u64 pgoff; |
| 4076 | } event_id; |
| 4077 | }; |
| 4078 | |
| 4079 | static void perf_event_mmap_output(struct perf_event *event, |
| 4080 | struct perf_mmap_event *mmap_event) |
| 4081 | { |
| 4082 | struct perf_output_handle handle; |
| 4083 | int size = mmap_event->event_id.header.size; |
| 4084 | int ret = perf_output_begin(&handle, event, size, 0, 0); |
| 4085 | |
| 4086 | if (ret) |
| 4087 | return; |
| 4088 | |
| 4089 | mmap_event->event_id.pid = perf_event_pid(event, current); |
| 4090 | mmap_event->event_id.tid = perf_event_tid(event, current); |
| 4091 | |
| 4092 | perf_output_put(&handle, mmap_event->event_id); |
| 4093 | perf_output_copy(&handle, mmap_event->file_name, |
| 4094 | mmap_event->file_size); |
| 4095 | perf_output_end(&handle); |
| 4096 | } |
| 4097 | |
| 4098 | static int perf_event_mmap_match(struct perf_event *event, |
Eric B Munson | 3af9e85 | 2010-05-18 15:30:49 +0100 | [diff] [blame] | 4099 | struct perf_mmap_event *mmap_event, |
| 4100 | int executable) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4101 | { |
Peter Zijlstra | 6f93d0a | 2010-02-14 11:12:04 +0100 | [diff] [blame] | 4102 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
Peter Zijlstra | 22e1908 | 2010-01-18 09:12:32 +0100 | [diff] [blame] | 4103 | return 0; |
| 4104 | |
Peter Zijlstra | 5d27c23 | 2009-12-17 13:16:32 +0100 | [diff] [blame] | 4105 | if (event->cpu != -1 && event->cpu != smp_processor_id()) |
| 4106 | return 0; |
| 4107 | |
Eric B Munson | 3af9e85 | 2010-05-18 15:30:49 +0100 | [diff] [blame] | 4108 | if ((!executable && event->attr.mmap_data) || |
| 4109 | (executable && event->attr.mmap)) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4110 | return 1; |
| 4111 | |
| 4112 | return 0; |
| 4113 | } |
| 4114 | |
| 4115 | static void perf_event_mmap_ctx(struct perf_event_context *ctx, |
Eric B Munson | 3af9e85 | 2010-05-18 15:30:49 +0100 | [diff] [blame] | 4116 | struct perf_mmap_event *mmap_event, |
| 4117 | int executable) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4118 | { |
| 4119 | struct perf_event *event; |
| 4120 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4121 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { |
Eric B Munson | 3af9e85 | 2010-05-18 15:30:49 +0100 | [diff] [blame] | 4122 | if (perf_event_mmap_match(event, mmap_event, executable)) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4123 | perf_event_mmap_output(event, mmap_event); |
| 4124 | } |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4125 | } |
| 4126 | |
| 4127 | static void perf_event_mmap_event(struct perf_mmap_event *mmap_event) |
| 4128 | { |
| 4129 | struct perf_cpu_context *cpuctx; |
| 4130 | struct perf_event_context *ctx; |
| 4131 | struct vm_area_struct *vma = mmap_event->vma; |
| 4132 | struct file *file = vma->vm_file; |
| 4133 | unsigned int size; |
| 4134 | char tmp[16]; |
| 4135 | char *buf = NULL; |
| 4136 | const char *name; |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 4137 | struct pmu *pmu; |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 4138 | int ctxn; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4139 | |
| 4140 | memset(tmp, 0, sizeof(tmp)); |
| 4141 | |
| 4142 | if (file) { |
| 4143 | /* |
| 4144 | * d_path works from the end of the buffer backwards, so we |
| 4145 | * need to add enough zero bytes after the string to handle |
| 4146 | * the 64bit alignment we do later. |
| 4147 | */ |
| 4148 | buf = kzalloc(PATH_MAX + sizeof(u64), GFP_KERNEL); |
| 4149 | if (!buf) { |
| 4150 | name = strncpy(tmp, "//enomem", sizeof(tmp)); |
| 4151 | goto got_name; |
| 4152 | } |
| 4153 | name = d_path(&file->f_path, buf, PATH_MAX); |
| 4154 | if (IS_ERR(name)) { |
| 4155 | name = strncpy(tmp, "//toolong", sizeof(tmp)); |
| 4156 | goto got_name; |
| 4157 | } |
| 4158 | } else { |
| 4159 | if (arch_vma_name(mmap_event->vma)) { |
| 4160 | name = strncpy(tmp, arch_vma_name(mmap_event->vma), |
| 4161 | sizeof(tmp)); |
| 4162 | goto got_name; |
| 4163 | } |
| 4164 | |
| 4165 | if (!vma->vm_mm) { |
| 4166 | name = strncpy(tmp, "[vdso]", sizeof(tmp)); |
| 4167 | goto got_name; |
Eric B Munson | 3af9e85 | 2010-05-18 15:30:49 +0100 | [diff] [blame] | 4168 | } else if (vma->vm_start <= vma->vm_mm->start_brk && |
| 4169 | vma->vm_end >= vma->vm_mm->brk) { |
| 4170 | name = strncpy(tmp, "[heap]", sizeof(tmp)); |
| 4171 | goto got_name; |
| 4172 | } else if (vma->vm_start <= vma->vm_mm->start_stack && |
| 4173 | vma->vm_end >= vma->vm_mm->start_stack) { |
| 4174 | name = strncpy(tmp, "[stack]", sizeof(tmp)); |
| 4175 | goto got_name; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4176 | } |
| 4177 | |
| 4178 | name = strncpy(tmp, "//anon", sizeof(tmp)); |
| 4179 | goto got_name; |
| 4180 | } |
| 4181 | |
| 4182 | got_name: |
| 4183 | size = ALIGN(strlen(name)+1, sizeof(u64)); |
| 4184 | |
| 4185 | mmap_event->file_name = name; |
| 4186 | mmap_event->file_size = size; |
| 4187 | |
| 4188 | mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size; |
| 4189 | |
Peter Zijlstra | f6d9dd2 | 2009-11-20 22:19:48 +0100 | [diff] [blame] | 4190 | rcu_read_lock(); |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 4191 | list_for_each_entry_rcu(pmu, &pmus, entry) { |
Peter Zijlstra | 41945f6 | 2010-09-16 19:17:24 +0200 | [diff] [blame] | 4192 | cpuctx = get_cpu_ptr(pmu->pmu_cpu_context); |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 4193 | perf_event_mmap_ctx(&cpuctx->ctx, mmap_event, |
| 4194 | vma->vm_flags & VM_EXEC); |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 4195 | |
| 4196 | ctxn = pmu->task_ctx_nr; |
| 4197 | if (ctxn < 0) |
Peter Zijlstra | 41945f6 | 2010-09-16 19:17:24 +0200 | [diff] [blame] | 4198 | goto next; |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 4199 | |
| 4200 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); |
| 4201 | if (ctx) { |
| 4202 | perf_event_mmap_ctx(ctx, mmap_event, |
| 4203 | vma->vm_flags & VM_EXEC); |
| 4204 | } |
Peter Zijlstra | 41945f6 | 2010-09-16 19:17:24 +0200 | [diff] [blame] | 4205 | next: |
| 4206 | put_cpu_ptr(pmu->pmu_cpu_context); |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 4207 | } |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4208 | rcu_read_unlock(); |
| 4209 | |
| 4210 | kfree(buf); |
| 4211 | } |
| 4212 | |
Eric B Munson | 3af9e85 | 2010-05-18 15:30:49 +0100 | [diff] [blame] | 4213 | void perf_event_mmap(struct vm_area_struct *vma) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4214 | { |
| 4215 | struct perf_mmap_event mmap_event; |
| 4216 | |
| 4217 | if (!atomic_read(&nr_mmap_events)) |
| 4218 | return; |
| 4219 | |
| 4220 | mmap_event = (struct perf_mmap_event){ |
| 4221 | .vma = vma, |
| 4222 | /* .file_name */ |
| 4223 | /* .file_size */ |
| 4224 | .event_id = { |
| 4225 | .header = { |
| 4226 | .type = PERF_RECORD_MMAP, |
Zhang, Yanmin | 39447b3 | 2010-04-19 13:32:41 +0800 | [diff] [blame] | 4227 | .misc = PERF_RECORD_MISC_USER, |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4228 | /* .size */ |
| 4229 | }, |
| 4230 | /* .pid */ |
| 4231 | /* .tid */ |
| 4232 | .start = vma->vm_start, |
| 4233 | .len = vma->vm_end - vma->vm_start, |
Peter Zijlstra | 3a0304e | 2010-02-26 10:33:41 +0100 | [diff] [blame] | 4234 | .pgoff = (u64)vma->vm_pgoff << PAGE_SHIFT, |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4235 | }, |
| 4236 | }; |
| 4237 | |
| 4238 | perf_event_mmap_event(&mmap_event); |
| 4239 | } |
| 4240 | |
| 4241 | /* |
| 4242 | * IRQ throttle logging |
| 4243 | */ |
| 4244 | |
| 4245 | static void perf_log_throttle(struct perf_event *event, int enable) |
| 4246 | { |
| 4247 | struct perf_output_handle handle; |
| 4248 | int ret; |
| 4249 | |
| 4250 | struct { |
| 4251 | struct perf_event_header header; |
| 4252 | u64 time; |
| 4253 | u64 id; |
| 4254 | u64 stream_id; |
| 4255 | } throttle_event = { |
| 4256 | .header = { |
| 4257 | .type = PERF_RECORD_THROTTLE, |
| 4258 | .misc = 0, |
| 4259 | .size = sizeof(throttle_event), |
| 4260 | }, |
| 4261 | .time = perf_clock(), |
| 4262 | .id = primary_event_id(event), |
| 4263 | .stream_id = event->id, |
| 4264 | }; |
| 4265 | |
| 4266 | if (enable) |
| 4267 | throttle_event.header.type = PERF_RECORD_UNTHROTTLE; |
| 4268 | |
| 4269 | ret = perf_output_begin(&handle, event, sizeof(throttle_event), 1, 0); |
| 4270 | if (ret) |
| 4271 | return; |
| 4272 | |
| 4273 | perf_output_put(&handle, throttle_event); |
| 4274 | perf_output_end(&handle); |
| 4275 | } |
| 4276 | |
| 4277 | /* |
| 4278 | * Generic event overflow handling, sampling. |
| 4279 | */ |
| 4280 | |
| 4281 | static int __perf_event_overflow(struct perf_event *event, int nmi, |
| 4282 | int throttle, struct perf_sample_data *data, |
| 4283 | struct pt_regs *regs) |
| 4284 | { |
| 4285 | int events = atomic_read(&event->event_limit); |
| 4286 | struct hw_perf_event *hwc = &event->hw; |
| 4287 | int ret = 0; |
| 4288 | |
Peter Zijlstra | 9639882 | 2010-11-24 18:55:29 +0100 | [diff] [blame] | 4289 | /* |
| 4290 | * Non-sampling counters might still use the PMI to fold short |
| 4291 | * hardware counters, ignore those. |
| 4292 | */ |
| 4293 | if (unlikely(!is_sampling_event(event))) |
| 4294 | return 0; |
| 4295 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4296 | if (!throttle) { |
| 4297 | hwc->interrupts++; |
| 4298 | } else { |
| 4299 | if (hwc->interrupts != MAX_INTERRUPTS) { |
| 4300 | hwc->interrupts++; |
| 4301 | if (HZ * hwc->interrupts > |
| 4302 | (u64)sysctl_perf_event_sample_rate) { |
| 4303 | hwc->interrupts = MAX_INTERRUPTS; |
| 4304 | perf_log_throttle(event, 0); |
| 4305 | ret = 1; |
| 4306 | } |
| 4307 | } else { |
| 4308 | /* |
| 4309 | * Keep re-disabling events even though on the previous |
| 4310 | * pass we disabled it - just in case we raced with a |
| 4311 | * sched-in and the event got enabled again: |
| 4312 | */ |
| 4313 | ret = 1; |
| 4314 | } |
| 4315 | } |
| 4316 | |
| 4317 | if (event->attr.freq) { |
| 4318 | u64 now = perf_clock(); |
Peter Zijlstra | abd5071 | 2010-01-26 18:50:16 +0100 | [diff] [blame] | 4319 | s64 delta = now - hwc->freq_time_stamp; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4320 | |
Peter Zijlstra | abd5071 | 2010-01-26 18:50:16 +0100 | [diff] [blame] | 4321 | hwc->freq_time_stamp = now; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4322 | |
Peter Zijlstra | abd5071 | 2010-01-26 18:50:16 +0100 | [diff] [blame] | 4323 | if (delta > 0 && delta < 2*TICK_NSEC) |
| 4324 | perf_adjust_period(event, delta, hwc->last_period); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4325 | } |
| 4326 | |
| 4327 | /* |
| 4328 | * XXX event_limit might not quite work as expected on inherited |
| 4329 | * events |
| 4330 | */ |
| 4331 | |
| 4332 | event->pending_kill = POLL_IN; |
| 4333 | if (events && atomic_dec_and_test(&event->event_limit)) { |
| 4334 | ret = 1; |
| 4335 | event->pending_kill = POLL_HUP; |
| 4336 | if (nmi) { |
| 4337 | event->pending_disable = 1; |
Peter Zijlstra | e360adb | 2010-10-14 14:01:34 +0800 | [diff] [blame] | 4338 | irq_work_queue(&event->pending); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4339 | } else |
| 4340 | perf_event_disable(event); |
| 4341 | } |
| 4342 | |
Peter Zijlstra | 453f19e | 2009-11-20 22:19:43 +0100 | [diff] [blame] | 4343 | if (event->overflow_handler) |
| 4344 | event->overflow_handler(event, nmi, data, regs); |
| 4345 | else |
| 4346 | perf_event_output(event, nmi, data, regs); |
| 4347 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4348 | return ret; |
| 4349 | } |
| 4350 | |
| 4351 | int perf_event_overflow(struct perf_event *event, int nmi, |
| 4352 | struct perf_sample_data *data, |
| 4353 | struct pt_regs *regs) |
| 4354 | { |
| 4355 | return __perf_event_overflow(event, nmi, 1, data, regs); |
| 4356 | } |
| 4357 | |
| 4358 | /* |
| 4359 | * Generic software event infrastructure |
| 4360 | */ |
| 4361 | |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 4362 | struct swevent_htable { |
| 4363 | struct swevent_hlist *swevent_hlist; |
| 4364 | struct mutex hlist_mutex; |
| 4365 | int hlist_refcount; |
| 4366 | |
| 4367 | /* Recursion avoidance in each contexts */ |
| 4368 | int recursion[PERF_NR_CONTEXTS]; |
| 4369 | }; |
| 4370 | |
| 4371 | static DEFINE_PER_CPU(struct swevent_htable, swevent_htable); |
| 4372 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4373 | /* |
| 4374 | * We directly increment event->count and keep a second value in |
| 4375 | * event->hw.period_left to count intervals. This period event |
| 4376 | * is kept in the range [-sample_period, 0] so that we can use the |
| 4377 | * sign as trigger. |
| 4378 | */ |
| 4379 | |
| 4380 | static u64 perf_swevent_set_period(struct perf_event *event) |
| 4381 | { |
| 4382 | struct hw_perf_event *hwc = &event->hw; |
| 4383 | u64 period = hwc->last_period; |
| 4384 | u64 nr, offset; |
| 4385 | s64 old, val; |
| 4386 | |
| 4387 | hwc->last_period = hwc->sample_period; |
| 4388 | |
| 4389 | again: |
Peter Zijlstra | e785059 | 2010-05-21 14:43:08 +0200 | [diff] [blame] | 4390 | old = val = local64_read(&hwc->period_left); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4391 | if (val < 0) |
| 4392 | return 0; |
| 4393 | |
| 4394 | nr = div64_u64(period + val, period); |
| 4395 | offset = nr * period; |
| 4396 | val -= offset; |
Peter Zijlstra | e785059 | 2010-05-21 14:43:08 +0200 | [diff] [blame] | 4397 | if (local64_cmpxchg(&hwc->period_left, old, val) != old) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4398 | goto again; |
| 4399 | |
| 4400 | return nr; |
| 4401 | } |
| 4402 | |
Peter Zijlstra | 0cff784 | 2009-11-20 22:19:44 +0100 | [diff] [blame] | 4403 | static void perf_swevent_overflow(struct perf_event *event, u64 overflow, |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4404 | int nmi, struct perf_sample_data *data, |
| 4405 | struct pt_regs *regs) |
| 4406 | { |
| 4407 | struct hw_perf_event *hwc = &event->hw; |
| 4408 | int throttle = 0; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4409 | |
| 4410 | data->period = event->hw.last_period; |
Peter Zijlstra | 0cff784 | 2009-11-20 22:19:44 +0100 | [diff] [blame] | 4411 | if (!overflow) |
| 4412 | overflow = perf_swevent_set_period(event); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4413 | |
| 4414 | if (hwc->interrupts == MAX_INTERRUPTS) |
| 4415 | return; |
| 4416 | |
| 4417 | for (; overflow; overflow--) { |
| 4418 | if (__perf_event_overflow(event, nmi, throttle, |
| 4419 | data, regs)) { |
| 4420 | /* |
| 4421 | * We inhibit the overflow from happening when |
| 4422 | * hwc->interrupts == MAX_INTERRUPTS. |
| 4423 | */ |
| 4424 | break; |
| 4425 | } |
| 4426 | throttle = 1; |
| 4427 | } |
| 4428 | } |
| 4429 | |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 4430 | static void perf_swevent_event(struct perf_event *event, u64 nr, |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4431 | int nmi, struct perf_sample_data *data, |
| 4432 | struct pt_regs *regs) |
| 4433 | { |
| 4434 | struct hw_perf_event *hwc = &event->hw; |
| 4435 | |
Peter Zijlstra | e785059 | 2010-05-21 14:43:08 +0200 | [diff] [blame] | 4436 | local64_add(nr, &event->count); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4437 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4438 | if (!regs) |
| 4439 | return; |
| 4440 | |
Franck Bui-Huu | 6c7e550 | 2010-11-23 16:21:43 +0100 | [diff] [blame] | 4441 | if (!is_sampling_event(event)) |
Peter Zijlstra | 0cff784 | 2009-11-20 22:19:44 +0100 | [diff] [blame] | 4442 | return; |
| 4443 | |
| 4444 | if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq) |
| 4445 | return perf_swevent_overflow(event, 1, nmi, data, regs); |
| 4446 | |
Peter Zijlstra | e785059 | 2010-05-21 14:43:08 +0200 | [diff] [blame] | 4447 | if (local64_add_negative(nr, &hwc->period_left)) |
Peter Zijlstra | 0cff784 | 2009-11-20 22:19:44 +0100 | [diff] [blame] | 4448 | return; |
| 4449 | |
| 4450 | perf_swevent_overflow(event, 0, nmi, data, regs); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4451 | } |
| 4452 | |
Frederic Weisbecker | f5ffe02 | 2009-11-23 15:42:34 +0100 | [diff] [blame] | 4453 | static int perf_exclude_event(struct perf_event *event, |
| 4454 | struct pt_regs *regs) |
| 4455 | { |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 4456 | if (event->hw.state & PERF_HES_STOPPED) |
| 4457 | return 0; |
| 4458 | |
Frederic Weisbecker | f5ffe02 | 2009-11-23 15:42:34 +0100 | [diff] [blame] | 4459 | if (regs) { |
| 4460 | if (event->attr.exclude_user && user_mode(regs)) |
| 4461 | return 1; |
| 4462 | |
| 4463 | if (event->attr.exclude_kernel && !user_mode(regs)) |
| 4464 | return 1; |
| 4465 | } |
| 4466 | |
| 4467 | return 0; |
| 4468 | } |
| 4469 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4470 | static int perf_swevent_match(struct perf_event *event, |
| 4471 | enum perf_type_id type, |
Li Zefan | 6fb2915 | 2009-10-15 11:21:42 +0800 | [diff] [blame] | 4472 | u32 event_id, |
| 4473 | struct perf_sample_data *data, |
| 4474 | struct pt_regs *regs) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4475 | { |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4476 | if (event->attr.type != type) |
| 4477 | return 0; |
Frederic Weisbecker | f5ffe02 | 2009-11-23 15:42:34 +0100 | [diff] [blame] | 4478 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4479 | if (event->attr.config != event_id) |
| 4480 | return 0; |
| 4481 | |
Frederic Weisbecker | f5ffe02 | 2009-11-23 15:42:34 +0100 | [diff] [blame] | 4482 | if (perf_exclude_event(event, regs)) |
| 4483 | return 0; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4484 | |
| 4485 | return 1; |
| 4486 | } |
| 4487 | |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4488 | static inline u64 swevent_hash(u64 type, u32 event_id) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4489 | { |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4490 | u64 val = event_id | (type << 32); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4491 | |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4492 | return hash_64(val, SWEVENT_HLIST_BITS); |
| 4493 | } |
| 4494 | |
Frederic Weisbecker | 49f135e | 2010-05-20 10:17:46 +0200 | [diff] [blame] | 4495 | static inline struct hlist_head * |
| 4496 | __find_swevent_head(struct swevent_hlist *hlist, u64 type, u32 event_id) |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4497 | { |
Frederic Weisbecker | 49f135e | 2010-05-20 10:17:46 +0200 | [diff] [blame] | 4498 | u64 hash = swevent_hash(type, event_id); |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4499 | |
Frederic Weisbecker | 49f135e | 2010-05-20 10:17:46 +0200 | [diff] [blame] | 4500 | return &hlist->heads[hash]; |
| 4501 | } |
| 4502 | |
| 4503 | /* For the read side: events when they trigger */ |
| 4504 | static inline struct hlist_head * |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 4505 | find_swevent_head_rcu(struct swevent_htable *swhash, u64 type, u32 event_id) |
Frederic Weisbecker | 49f135e | 2010-05-20 10:17:46 +0200 | [diff] [blame] | 4506 | { |
| 4507 | struct swevent_hlist *hlist; |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4508 | |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 4509 | hlist = rcu_dereference(swhash->swevent_hlist); |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4510 | if (!hlist) |
| 4511 | return NULL; |
| 4512 | |
Frederic Weisbecker | 49f135e | 2010-05-20 10:17:46 +0200 | [diff] [blame] | 4513 | return __find_swevent_head(hlist, type, event_id); |
| 4514 | } |
| 4515 | |
| 4516 | /* For the event head insertion and removal in the hlist */ |
| 4517 | static inline struct hlist_head * |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 4518 | find_swevent_head(struct swevent_htable *swhash, struct perf_event *event) |
Frederic Weisbecker | 49f135e | 2010-05-20 10:17:46 +0200 | [diff] [blame] | 4519 | { |
| 4520 | struct swevent_hlist *hlist; |
| 4521 | u32 event_id = event->attr.config; |
| 4522 | u64 type = event->attr.type; |
| 4523 | |
| 4524 | /* |
| 4525 | * Event scheduling is always serialized against hlist allocation |
| 4526 | * and release. Which makes the protected version suitable here. |
| 4527 | * The context lock guarantees that. |
| 4528 | */ |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 4529 | hlist = rcu_dereference_protected(swhash->swevent_hlist, |
Frederic Weisbecker | 49f135e | 2010-05-20 10:17:46 +0200 | [diff] [blame] | 4530 | lockdep_is_held(&event->ctx->lock)); |
| 4531 | if (!hlist) |
| 4532 | return NULL; |
| 4533 | |
| 4534 | return __find_swevent_head(hlist, type, event_id); |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4535 | } |
| 4536 | |
| 4537 | static void do_perf_sw_event(enum perf_type_id type, u32 event_id, |
| 4538 | u64 nr, int nmi, |
| 4539 | struct perf_sample_data *data, |
| 4540 | struct pt_regs *regs) |
| 4541 | { |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 4542 | struct swevent_htable *swhash = &__get_cpu_var(swevent_htable); |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4543 | struct perf_event *event; |
| 4544 | struct hlist_node *node; |
| 4545 | struct hlist_head *head; |
| 4546 | |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4547 | rcu_read_lock(); |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 4548 | head = find_swevent_head_rcu(swhash, type, event_id); |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4549 | if (!head) |
| 4550 | goto end; |
| 4551 | |
| 4552 | hlist_for_each_entry_rcu(event, node, head, hlist_entry) { |
Li Zefan | 6fb2915 | 2009-10-15 11:21:42 +0800 | [diff] [blame] | 4553 | if (perf_swevent_match(event, type, event_id, data, regs)) |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 4554 | perf_swevent_event(event, nr, nmi, data, regs); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4555 | } |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4556 | end: |
| 4557 | rcu_read_unlock(); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4558 | } |
| 4559 | |
Peter Zijlstra | 4ed7c92 | 2009-11-23 11:37:29 +0100 | [diff] [blame] | 4560 | int perf_swevent_get_recursion_context(void) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4561 | { |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 4562 | struct swevent_htable *swhash = &__get_cpu_var(swevent_htable); |
Frederic Weisbecker | ce71b9d | 2009-11-22 05:26:55 +0100 | [diff] [blame] | 4563 | |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 4564 | return get_recursion_context(swhash->recursion); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4565 | } |
Ingo Molnar | 645e8cc | 2009-11-22 12:20:19 +0100 | [diff] [blame] | 4566 | EXPORT_SYMBOL_GPL(perf_swevent_get_recursion_context); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4567 | |
Peter Zijlstra | ecc55f8 | 2010-05-21 15:11:34 +0200 | [diff] [blame] | 4568 | void inline perf_swevent_put_recursion_context(int rctx) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4569 | { |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 4570 | struct swevent_htable *swhash = &__get_cpu_var(swevent_htable); |
Frederic Weisbecker | 927c7a9 | 2010-07-01 16:20:36 +0200 | [diff] [blame] | 4571 | |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 4572 | put_recursion_context(swhash->recursion, rctx); |
Frederic Weisbecker | ce71b9d | 2009-11-22 05:26:55 +0100 | [diff] [blame] | 4573 | } |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4574 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4575 | void __perf_sw_event(u32 event_id, u64 nr, int nmi, |
| 4576 | struct pt_regs *regs, u64 addr) |
| 4577 | { |
Ingo Molnar | a4234bf | 2009-11-23 10:57:59 +0100 | [diff] [blame] | 4578 | struct perf_sample_data data; |
Peter Zijlstra | 4ed7c92 | 2009-11-23 11:37:29 +0100 | [diff] [blame] | 4579 | int rctx; |
| 4580 | |
Peter Zijlstra | 1c024eca | 2010-05-19 14:02:22 +0200 | [diff] [blame] | 4581 | preempt_disable_notrace(); |
Peter Zijlstra | 4ed7c92 | 2009-11-23 11:37:29 +0100 | [diff] [blame] | 4582 | rctx = perf_swevent_get_recursion_context(); |
| 4583 | if (rctx < 0) |
| 4584 | return; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4585 | |
Peter Zijlstra | dc1d628 | 2010-03-03 15:55:04 +0100 | [diff] [blame] | 4586 | perf_sample_data_init(&data, addr); |
Ingo Molnar | a4234bf | 2009-11-23 10:57:59 +0100 | [diff] [blame] | 4587 | |
| 4588 | do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, nmi, &data, regs); |
Peter Zijlstra | 4ed7c92 | 2009-11-23 11:37:29 +0100 | [diff] [blame] | 4589 | |
| 4590 | perf_swevent_put_recursion_context(rctx); |
Peter Zijlstra | 1c024eca | 2010-05-19 14:02:22 +0200 | [diff] [blame] | 4591 | preempt_enable_notrace(); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4592 | } |
| 4593 | |
| 4594 | static void perf_swevent_read(struct perf_event *event) |
| 4595 | { |
| 4596 | } |
| 4597 | |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 4598 | static int perf_swevent_add(struct perf_event *event, int flags) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4599 | { |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 4600 | struct swevent_htable *swhash = &__get_cpu_var(swevent_htable); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4601 | struct hw_perf_event *hwc = &event->hw; |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4602 | struct hlist_head *head; |
| 4603 | |
Franck Bui-Huu | 6c7e550 | 2010-11-23 16:21:43 +0100 | [diff] [blame] | 4604 | if (is_sampling_event(event)) { |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4605 | hwc->last_period = hwc->sample_period; |
| 4606 | perf_swevent_set_period(event); |
| 4607 | } |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4608 | |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 4609 | hwc->state = !(flags & PERF_EF_START); |
| 4610 | |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 4611 | head = find_swevent_head(swhash, event); |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4612 | if (WARN_ON_ONCE(!head)) |
| 4613 | return -EINVAL; |
| 4614 | |
| 4615 | hlist_add_head_rcu(&event->hlist_entry, head); |
| 4616 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4617 | return 0; |
| 4618 | } |
| 4619 | |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 4620 | static void perf_swevent_del(struct perf_event *event, int flags) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4621 | { |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4622 | hlist_del_rcu(&event->hlist_entry); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4623 | } |
| 4624 | |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 4625 | static void perf_swevent_start(struct perf_event *event, int flags) |
Peter Zijlstra | c6df8d5 | 2010-06-03 11:21:20 +0200 | [diff] [blame] | 4626 | { |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 4627 | event->hw.state = 0; |
Peter Zijlstra | c6df8d5 | 2010-06-03 11:21:20 +0200 | [diff] [blame] | 4628 | } |
| 4629 | |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 4630 | static void perf_swevent_stop(struct perf_event *event, int flags) |
Peter Zijlstra | c6df8d5 | 2010-06-03 11:21:20 +0200 | [diff] [blame] | 4631 | { |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 4632 | event->hw.state = PERF_HES_STOPPED; |
Peter Zijlstra | c6df8d5 | 2010-06-03 11:21:20 +0200 | [diff] [blame] | 4633 | } |
| 4634 | |
Frederic Weisbecker | 49f135e | 2010-05-20 10:17:46 +0200 | [diff] [blame] | 4635 | /* Deref the hlist from the update side */ |
| 4636 | static inline struct swevent_hlist * |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 4637 | swevent_hlist_deref(struct swevent_htable *swhash) |
Frederic Weisbecker | 49f135e | 2010-05-20 10:17:46 +0200 | [diff] [blame] | 4638 | { |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 4639 | return rcu_dereference_protected(swhash->swevent_hlist, |
| 4640 | lockdep_is_held(&swhash->hlist_mutex)); |
Frederic Weisbecker | 49f135e | 2010-05-20 10:17:46 +0200 | [diff] [blame] | 4641 | } |
| 4642 | |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4643 | static void swevent_hlist_release_rcu(struct rcu_head *rcu_head) |
| 4644 | { |
| 4645 | struct swevent_hlist *hlist; |
| 4646 | |
| 4647 | hlist = container_of(rcu_head, struct swevent_hlist, rcu_head); |
| 4648 | kfree(hlist); |
| 4649 | } |
| 4650 | |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 4651 | static void swevent_hlist_release(struct swevent_htable *swhash) |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4652 | { |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 4653 | struct swevent_hlist *hlist = swevent_hlist_deref(swhash); |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4654 | |
Frederic Weisbecker | 49f135e | 2010-05-20 10:17:46 +0200 | [diff] [blame] | 4655 | if (!hlist) |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4656 | return; |
| 4657 | |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 4658 | rcu_assign_pointer(swhash->swevent_hlist, NULL); |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4659 | call_rcu(&hlist->rcu_head, swevent_hlist_release_rcu); |
| 4660 | } |
| 4661 | |
| 4662 | static void swevent_hlist_put_cpu(struct perf_event *event, int cpu) |
| 4663 | { |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 4664 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4665 | |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 4666 | mutex_lock(&swhash->hlist_mutex); |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4667 | |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 4668 | if (!--swhash->hlist_refcount) |
| 4669 | swevent_hlist_release(swhash); |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4670 | |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 4671 | mutex_unlock(&swhash->hlist_mutex); |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4672 | } |
| 4673 | |
| 4674 | static void swevent_hlist_put(struct perf_event *event) |
| 4675 | { |
| 4676 | int cpu; |
| 4677 | |
| 4678 | if (event->cpu != -1) { |
| 4679 | swevent_hlist_put_cpu(event, event->cpu); |
| 4680 | return; |
| 4681 | } |
| 4682 | |
| 4683 | for_each_possible_cpu(cpu) |
| 4684 | swevent_hlist_put_cpu(event, cpu); |
| 4685 | } |
| 4686 | |
| 4687 | static int swevent_hlist_get_cpu(struct perf_event *event, int cpu) |
| 4688 | { |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 4689 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4690 | int err = 0; |
| 4691 | |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 4692 | mutex_lock(&swhash->hlist_mutex); |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4693 | |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 4694 | if (!swevent_hlist_deref(swhash) && cpu_online(cpu)) { |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4695 | struct swevent_hlist *hlist; |
| 4696 | |
| 4697 | hlist = kzalloc(sizeof(*hlist), GFP_KERNEL); |
| 4698 | if (!hlist) { |
| 4699 | err = -ENOMEM; |
| 4700 | goto exit; |
| 4701 | } |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 4702 | rcu_assign_pointer(swhash->swevent_hlist, hlist); |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4703 | } |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 4704 | swhash->hlist_refcount++; |
Peter Zijlstra | 9ed6060 | 2010-06-11 17:36:35 +0200 | [diff] [blame] | 4705 | exit: |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 4706 | mutex_unlock(&swhash->hlist_mutex); |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4707 | |
| 4708 | return err; |
| 4709 | } |
| 4710 | |
| 4711 | static int swevent_hlist_get(struct perf_event *event) |
| 4712 | { |
| 4713 | int err; |
| 4714 | int cpu, failed_cpu; |
| 4715 | |
| 4716 | if (event->cpu != -1) |
| 4717 | return swevent_hlist_get_cpu(event, event->cpu); |
| 4718 | |
| 4719 | get_online_cpus(); |
| 4720 | for_each_possible_cpu(cpu) { |
| 4721 | err = swevent_hlist_get_cpu(event, cpu); |
| 4722 | if (err) { |
| 4723 | failed_cpu = cpu; |
| 4724 | goto fail; |
| 4725 | } |
| 4726 | } |
| 4727 | put_online_cpus(); |
| 4728 | |
| 4729 | return 0; |
Peter Zijlstra | 9ed6060 | 2010-06-11 17:36:35 +0200 | [diff] [blame] | 4730 | fail: |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4731 | for_each_possible_cpu(cpu) { |
| 4732 | if (cpu == failed_cpu) |
| 4733 | break; |
| 4734 | swevent_hlist_put_cpu(event, cpu); |
| 4735 | } |
| 4736 | |
| 4737 | put_online_cpus(); |
| 4738 | return err; |
| 4739 | } |
| 4740 | |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 4741 | atomic_t perf_swevent_enabled[PERF_COUNT_SW_MAX]; |
Frederic Weisbecker | 95476b6 | 2010-04-14 23:42:18 +0200 | [diff] [blame] | 4742 | |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 4743 | static void sw_perf_event_destroy(struct perf_event *event) |
| 4744 | { |
| 4745 | u64 event_id = event->attr.config; |
| 4746 | |
| 4747 | WARN_ON(event->parent); |
| 4748 | |
Peter Zijlstra | 7e54a5a | 2010-10-14 22:32:45 +0200 | [diff] [blame] | 4749 | jump_label_dec(&perf_swevent_enabled[event_id]); |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 4750 | swevent_hlist_put(event); |
| 4751 | } |
| 4752 | |
| 4753 | static int perf_swevent_init(struct perf_event *event) |
| 4754 | { |
| 4755 | int event_id = event->attr.config; |
| 4756 | |
| 4757 | if (event->attr.type != PERF_TYPE_SOFTWARE) |
| 4758 | return -ENOENT; |
| 4759 | |
| 4760 | switch (event_id) { |
| 4761 | case PERF_COUNT_SW_CPU_CLOCK: |
| 4762 | case PERF_COUNT_SW_TASK_CLOCK: |
| 4763 | return -ENOENT; |
| 4764 | |
| 4765 | default: |
| 4766 | break; |
| 4767 | } |
| 4768 | |
| 4769 | if (event_id > PERF_COUNT_SW_MAX) |
| 4770 | return -ENOENT; |
| 4771 | |
| 4772 | if (!event->parent) { |
| 4773 | int err; |
| 4774 | |
| 4775 | err = swevent_hlist_get(event); |
| 4776 | if (err) |
| 4777 | return err; |
| 4778 | |
Peter Zijlstra | 7e54a5a | 2010-10-14 22:32:45 +0200 | [diff] [blame] | 4779 | jump_label_inc(&perf_swevent_enabled[event_id]); |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 4780 | event->destroy = sw_perf_event_destroy; |
| 4781 | } |
| 4782 | |
| 4783 | return 0; |
| 4784 | } |
| 4785 | |
| 4786 | static struct pmu perf_swevent = { |
Peter Zijlstra | 89a1e18 | 2010-09-07 17:34:50 +0200 | [diff] [blame] | 4787 | .task_ctx_nr = perf_sw_context, |
| 4788 | |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 4789 | .event_init = perf_swevent_init, |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 4790 | .add = perf_swevent_add, |
| 4791 | .del = perf_swevent_del, |
| 4792 | .start = perf_swevent_start, |
| 4793 | .stop = perf_swevent_stop, |
Peter Zijlstra | 1c024eca | 2010-05-19 14:02:22 +0200 | [diff] [blame] | 4794 | .read = perf_swevent_read, |
Peter Zijlstra | 1c024eca | 2010-05-19 14:02:22 +0200 | [diff] [blame] | 4795 | }; |
Frederic Weisbecker | 95476b6 | 2010-04-14 23:42:18 +0200 | [diff] [blame] | 4796 | |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 4797 | #ifdef CONFIG_EVENT_TRACING |
| 4798 | |
Peter Zijlstra | 1c024eca | 2010-05-19 14:02:22 +0200 | [diff] [blame] | 4799 | static int perf_tp_filter_match(struct perf_event *event, |
Frederic Weisbecker | 95476b6 | 2010-04-14 23:42:18 +0200 | [diff] [blame] | 4800 | struct perf_sample_data *data) |
| 4801 | { |
| 4802 | void *record = data->raw->data; |
| 4803 | |
| 4804 | if (likely(!event->filter) || filter_match_preds(event->filter, record)) |
| 4805 | return 1; |
| 4806 | return 0; |
| 4807 | } |
| 4808 | |
Peter Zijlstra | 1c024eca | 2010-05-19 14:02:22 +0200 | [diff] [blame] | 4809 | static int perf_tp_event_match(struct perf_event *event, |
| 4810 | struct perf_sample_data *data, |
| 4811 | struct pt_regs *regs) |
| 4812 | { |
Peter Zijlstra | 580d607 | 2010-05-20 20:54:31 +0200 | [diff] [blame] | 4813 | /* |
| 4814 | * All tracepoints are from kernel-space. |
| 4815 | */ |
| 4816 | if (event->attr.exclude_kernel) |
Peter Zijlstra | 1c024eca | 2010-05-19 14:02:22 +0200 | [diff] [blame] | 4817 | return 0; |
| 4818 | |
| 4819 | if (!perf_tp_filter_match(event, data)) |
| 4820 | return 0; |
| 4821 | |
| 4822 | return 1; |
| 4823 | } |
| 4824 | |
| 4825 | void perf_tp_event(u64 addr, u64 count, void *record, int entry_size, |
Peter Zijlstra | ecc55f8 | 2010-05-21 15:11:34 +0200 | [diff] [blame] | 4826 | struct pt_regs *regs, struct hlist_head *head, int rctx) |
Peter Zijlstra | 1c024eca | 2010-05-19 14:02:22 +0200 | [diff] [blame] | 4827 | { |
| 4828 | struct perf_sample_data data; |
| 4829 | struct perf_event *event; |
| 4830 | struct hlist_node *node; |
| 4831 | |
| 4832 | struct perf_raw_record raw = { |
| 4833 | .size = entry_size, |
| 4834 | .data = record, |
| 4835 | }; |
| 4836 | |
| 4837 | perf_sample_data_init(&data, addr); |
| 4838 | data.raw = &raw; |
| 4839 | |
Peter Zijlstra | 1c024eca | 2010-05-19 14:02:22 +0200 | [diff] [blame] | 4840 | hlist_for_each_entry_rcu(event, node, head, hlist_entry) { |
| 4841 | if (perf_tp_event_match(event, &data, regs)) |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 4842 | perf_swevent_event(event, count, 1, &data, regs); |
Peter Zijlstra | 1c024eca | 2010-05-19 14:02:22 +0200 | [diff] [blame] | 4843 | } |
Peter Zijlstra | ecc55f8 | 2010-05-21 15:11:34 +0200 | [diff] [blame] | 4844 | |
| 4845 | perf_swevent_put_recursion_context(rctx); |
Peter Zijlstra | 1c024eca | 2010-05-19 14:02:22 +0200 | [diff] [blame] | 4846 | } |
| 4847 | EXPORT_SYMBOL_GPL(perf_tp_event); |
| 4848 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4849 | static void tp_perf_event_destroy(struct perf_event *event) |
| 4850 | { |
Peter Zijlstra | 1c024eca | 2010-05-19 14:02:22 +0200 | [diff] [blame] | 4851 | perf_trace_destroy(event); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4852 | } |
| 4853 | |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 4854 | static int perf_tp_event_init(struct perf_event *event) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4855 | { |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 4856 | int err; |
| 4857 | |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 4858 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
| 4859 | return -ENOENT; |
| 4860 | |
Peter Zijlstra | 1c024eca | 2010-05-19 14:02:22 +0200 | [diff] [blame] | 4861 | err = perf_trace_init(event); |
| 4862 | if (err) |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 4863 | return err; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4864 | |
| 4865 | event->destroy = tp_perf_event_destroy; |
| 4866 | |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 4867 | return 0; |
| 4868 | } |
| 4869 | |
| 4870 | static struct pmu perf_tracepoint = { |
Peter Zijlstra | 89a1e18 | 2010-09-07 17:34:50 +0200 | [diff] [blame] | 4871 | .task_ctx_nr = perf_sw_context, |
| 4872 | |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 4873 | .event_init = perf_tp_event_init, |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 4874 | .add = perf_trace_add, |
| 4875 | .del = perf_trace_del, |
| 4876 | .start = perf_swevent_start, |
| 4877 | .stop = perf_swevent_stop, |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 4878 | .read = perf_swevent_read, |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 4879 | }; |
| 4880 | |
| 4881 | static inline void perf_tp_register(void) |
| 4882 | { |
| 4883 | perf_pmu_register(&perf_tracepoint); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4884 | } |
Li Zefan | 6fb2915 | 2009-10-15 11:21:42 +0800 | [diff] [blame] | 4885 | |
| 4886 | static int perf_event_set_filter(struct perf_event *event, void __user *arg) |
| 4887 | { |
| 4888 | char *filter_str; |
| 4889 | int ret; |
| 4890 | |
| 4891 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
| 4892 | return -EINVAL; |
| 4893 | |
| 4894 | filter_str = strndup_user(arg, PAGE_SIZE); |
| 4895 | if (IS_ERR(filter_str)) |
| 4896 | return PTR_ERR(filter_str); |
| 4897 | |
| 4898 | ret = ftrace_profile_set_filter(event, event->attr.config, filter_str); |
| 4899 | |
| 4900 | kfree(filter_str); |
| 4901 | return ret; |
| 4902 | } |
| 4903 | |
| 4904 | static void perf_event_free_filter(struct perf_event *event) |
| 4905 | { |
| 4906 | ftrace_profile_free_filter(event); |
| 4907 | } |
| 4908 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4909 | #else |
Li Zefan | 6fb2915 | 2009-10-15 11:21:42 +0800 | [diff] [blame] | 4910 | |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 4911 | static inline void perf_tp_register(void) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4912 | { |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4913 | } |
Li Zefan | 6fb2915 | 2009-10-15 11:21:42 +0800 | [diff] [blame] | 4914 | |
| 4915 | static int perf_event_set_filter(struct perf_event *event, void __user *arg) |
| 4916 | { |
| 4917 | return -ENOENT; |
| 4918 | } |
| 4919 | |
| 4920 | static void perf_event_free_filter(struct perf_event *event) |
| 4921 | { |
| 4922 | } |
| 4923 | |
Li Zefan | 07b139c | 2009-12-21 14:27:35 +0800 | [diff] [blame] | 4924 | #endif /* CONFIG_EVENT_TRACING */ |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4925 | |
Frederic Weisbecker | 24f1e32c | 2009-09-09 19:22:48 +0200 | [diff] [blame] | 4926 | #ifdef CONFIG_HAVE_HW_BREAKPOINT |
Frederic Weisbecker | f5ffe02 | 2009-11-23 15:42:34 +0100 | [diff] [blame] | 4927 | void perf_bp_event(struct perf_event *bp, void *data) |
Frederic Weisbecker | 24f1e32c | 2009-09-09 19:22:48 +0200 | [diff] [blame] | 4928 | { |
Frederic Weisbecker | f5ffe02 | 2009-11-23 15:42:34 +0100 | [diff] [blame] | 4929 | struct perf_sample_data sample; |
| 4930 | struct pt_regs *regs = data; |
| 4931 | |
Peter Zijlstra | dc1d628 | 2010-03-03 15:55:04 +0100 | [diff] [blame] | 4932 | perf_sample_data_init(&sample, bp->attr.bp_addr); |
Frederic Weisbecker | f5ffe02 | 2009-11-23 15:42:34 +0100 | [diff] [blame] | 4933 | |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 4934 | if (!bp->hw.state && !perf_exclude_event(bp, regs)) |
| 4935 | perf_swevent_event(bp, 1, 1, &sample, regs); |
Frederic Weisbecker | 24f1e32c | 2009-09-09 19:22:48 +0200 | [diff] [blame] | 4936 | } |
| 4937 | #endif |
| 4938 | |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 4939 | /* |
| 4940 | * hrtimer based swevent callback |
| 4941 | */ |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4942 | |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 4943 | static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4944 | { |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 4945 | enum hrtimer_restart ret = HRTIMER_RESTART; |
| 4946 | struct perf_sample_data data; |
| 4947 | struct pt_regs *regs; |
| 4948 | struct perf_event *event; |
| 4949 | u64 period; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4950 | |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 4951 | event = container_of(hrtimer, struct perf_event, hw.hrtimer); |
| 4952 | event->pmu->read(event); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4953 | |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 4954 | perf_sample_data_init(&data, 0); |
| 4955 | data.period = event->hw.last_period; |
| 4956 | regs = get_irq_regs(); |
| 4957 | |
| 4958 | if (regs && !perf_exclude_event(event, regs)) { |
| 4959 | if (!(event->attr.exclude_idle && current->pid == 0)) |
| 4960 | if (perf_event_overflow(event, 0, &data, regs)) |
| 4961 | ret = HRTIMER_NORESTART; |
| 4962 | } |
| 4963 | |
| 4964 | period = max_t(u64, 10000, event->hw.sample_period); |
| 4965 | hrtimer_forward_now(hrtimer, ns_to_ktime(period)); |
| 4966 | |
| 4967 | return ret; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4968 | } |
| 4969 | |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 4970 | static void perf_swevent_start_hrtimer(struct perf_event *event) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 4971 | { |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 4972 | struct hw_perf_event *hwc = &event->hw; |
Franck Bui-Huu | 5d508e8 | 2010-11-23 16:21:45 +0100 | [diff] [blame] | 4973 | s64 period; |
| 4974 | |
| 4975 | if (!is_sampling_event(event)) |
| 4976 | return; |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 4977 | |
| 4978 | hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); |
| 4979 | hwc->hrtimer.function = perf_swevent_hrtimer; |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 4980 | |
Franck Bui-Huu | 5d508e8 | 2010-11-23 16:21:45 +0100 | [diff] [blame] | 4981 | period = local64_read(&hwc->period_left); |
| 4982 | if (period) { |
| 4983 | if (period < 0) |
| 4984 | period = 10000; |
Peter Zijlstra | fa407f3 | 2010-06-24 12:35:12 +0200 | [diff] [blame] | 4985 | |
Franck Bui-Huu | 5d508e8 | 2010-11-23 16:21:45 +0100 | [diff] [blame] | 4986 | local64_set(&hwc->period_left, 0); |
| 4987 | } else { |
| 4988 | period = max_t(u64, 10000, hwc->sample_period); |
| 4989 | } |
| 4990 | __hrtimer_start_range_ns(&hwc->hrtimer, |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 4991 | ns_to_ktime(period), 0, |
Peter Zijlstra | b5ab4cd | 2010-09-06 16:32:21 +0200 | [diff] [blame] | 4992 | HRTIMER_MODE_REL_PINNED, 0); |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 4993 | } |
| 4994 | |
| 4995 | static void perf_swevent_cancel_hrtimer(struct perf_event *event) |
| 4996 | { |
| 4997 | struct hw_perf_event *hwc = &event->hw; |
| 4998 | |
Franck Bui-Huu | 6c7e550 | 2010-11-23 16:21:43 +0100 | [diff] [blame] | 4999 | if (is_sampling_event(event)) { |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5000 | ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer); |
Peter Zijlstra | fa407f3 | 2010-06-24 12:35:12 +0200 | [diff] [blame] | 5001 | local64_set(&hwc->period_left, ktime_to_ns(remaining)); |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5002 | |
| 5003 | hrtimer_cancel(&hwc->hrtimer); |
| 5004 | } |
| 5005 | } |
| 5006 | |
| 5007 | /* |
| 5008 | * Software event: cpu wall time clock |
| 5009 | */ |
| 5010 | |
| 5011 | static void cpu_clock_event_update(struct perf_event *event) |
| 5012 | { |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5013 | s64 prev; |
| 5014 | u64 now; |
| 5015 | |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 5016 | now = local_clock(); |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5017 | prev = local64_xchg(&event->hw.prev_count, now); |
| 5018 | local64_add(now - prev, &event->count); |
| 5019 | } |
| 5020 | |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 5021 | static void cpu_clock_event_start(struct perf_event *event, int flags) |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5022 | { |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 5023 | local64_set(&event->hw.prev_count, local_clock()); |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5024 | perf_swevent_start_hrtimer(event); |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 5025 | } |
| 5026 | |
| 5027 | static void cpu_clock_event_stop(struct perf_event *event, int flags) |
| 5028 | { |
| 5029 | perf_swevent_cancel_hrtimer(event); |
| 5030 | cpu_clock_event_update(event); |
| 5031 | } |
| 5032 | |
| 5033 | static int cpu_clock_event_add(struct perf_event *event, int flags) |
| 5034 | { |
| 5035 | if (flags & PERF_EF_START) |
| 5036 | cpu_clock_event_start(event, flags); |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5037 | |
| 5038 | return 0; |
| 5039 | } |
| 5040 | |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 5041 | static void cpu_clock_event_del(struct perf_event *event, int flags) |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5042 | { |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 5043 | cpu_clock_event_stop(event, flags); |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5044 | } |
| 5045 | |
| 5046 | static void cpu_clock_event_read(struct perf_event *event) |
| 5047 | { |
| 5048 | cpu_clock_event_update(event); |
| 5049 | } |
| 5050 | |
| 5051 | static int cpu_clock_event_init(struct perf_event *event) |
| 5052 | { |
| 5053 | if (event->attr.type != PERF_TYPE_SOFTWARE) |
| 5054 | return -ENOENT; |
| 5055 | |
| 5056 | if (event->attr.config != PERF_COUNT_SW_CPU_CLOCK) |
| 5057 | return -ENOENT; |
| 5058 | |
| 5059 | return 0; |
| 5060 | } |
| 5061 | |
| 5062 | static struct pmu perf_cpu_clock = { |
Peter Zijlstra | 89a1e18 | 2010-09-07 17:34:50 +0200 | [diff] [blame] | 5063 | .task_ctx_nr = perf_sw_context, |
| 5064 | |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5065 | .event_init = cpu_clock_event_init, |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 5066 | .add = cpu_clock_event_add, |
| 5067 | .del = cpu_clock_event_del, |
| 5068 | .start = cpu_clock_event_start, |
| 5069 | .stop = cpu_clock_event_stop, |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5070 | .read = cpu_clock_event_read, |
| 5071 | }; |
| 5072 | |
| 5073 | /* |
| 5074 | * Software event: task time clock |
| 5075 | */ |
| 5076 | |
| 5077 | static void task_clock_event_update(struct perf_event *event, u64 now) |
| 5078 | { |
| 5079 | u64 prev; |
| 5080 | s64 delta; |
| 5081 | |
| 5082 | prev = local64_xchg(&event->hw.prev_count, now); |
| 5083 | delta = now - prev; |
| 5084 | local64_add(delta, &event->count); |
| 5085 | } |
| 5086 | |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 5087 | static void task_clock_event_start(struct perf_event *event, int flags) |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5088 | { |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 5089 | local64_set(&event->hw.prev_count, event->ctx->time); |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5090 | perf_swevent_start_hrtimer(event); |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 5091 | } |
| 5092 | |
| 5093 | static void task_clock_event_stop(struct perf_event *event, int flags) |
| 5094 | { |
| 5095 | perf_swevent_cancel_hrtimer(event); |
| 5096 | task_clock_event_update(event, event->ctx->time); |
| 5097 | } |
| 5098 | |
| 5099 | static int task_clock_event_add(struct perf_event *event, int flags) |
| 5100 | { |
| 5101 | if (flags & PERF_EF_START) |
| 5102 | task_clock_event_start(event, flags); |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5103 | |
| 5104 | return 0; |
| 5105 | } |
| 5106 | |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 5107 | static void task_clock_event_del(struct perf_event *event, int flags) |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5108 | { |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 5109 | task_clock_event_stop(event, PERF_EF_UPDATE); |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5110 | } |
| 5111 | |
| 5112 | static void task_clock_event_read(struct perf_event *event) |
| 5113 | { |
| 5114 | u64 time; |
| 5115 | |
| 5116 | if (!in_nmi()) { |
| 5117 | update_context_time(event->ctx); |
| 5118 | time = event->ctx->time; |
| 5119 | } else { |
| 5120 | u64 now = perf_clock(); |
| 5121 | u64 delta = now - event->ctx->timestamp; |
| 5122 | time = event->ctx->time + delta; |
| 5123 | } |
| 5124 | |
| 5125 | task_clock_event_update(event, time); |
| 5126 | } |
| 5127 | |
| 5128 | static int task_clock_event_init(struct perf_event *event) |
| 5129 | { |
| 5130 | if (event->attr.type != PERF_TYPE_SOFTWARE) |
| 5131 | return -ENOENT; |
| 5132 | |
| 5133 | if (event->attr.config != PERF_COUNT_SW_TASK_CLOCK) |
| 5134 | return -ENOENT; |
| 5135 | |
| 5136 | return 0; |
| 5137 | } |
| 5138 | |
| 5139 | static struct pmu perf_task_clock = { |
Peter Zijlstra | 89a1e18 | 2010-09-07 17:34:50 +0200 | [diff] [blame] | 5140 | .task_ctx_nr = perf_sw_context, |
| 5141 | |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5142 | .event_init = task_clock_event_init, |
Peter Zijlstra | a4eaf7f | 2010-06-16 14:37:10 +0200 | [diff] [blame] | 5143 | .add = task_clock_event_add, |
| 5144 | .del = task_clock_event_del, |
| 5145 | .start = task_clock_event_start, |
| 5146 | .stop = task_clock_event_stop, |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5147 | .read = task_clock_event_read, |
| 5148 | }; |
| 5149 | |
Peter Zijlstra | ad5133b | 2010-06-15 12:22:39 +0200 | [diff] [blame] | 5150 | static void perf_pmu_nop_void(struct pmu *pmu) |
| 5151 | { |
| 5152 | } |
| 5153 | |
| 5154 | static int perf_pmu_nop_int(struct pmu *pmu) |
| 5155 | { |
| 5156 | return 0; |
| 5157 | } |
| 5158 | |
| 5159 | static void perf_pmu_start_txn(struct pmu *pmu) |
| 5160 | { |
| 5161 | perf_pmu_disable(pmu); |
| 5162 | } |
| 5163 | |
| 5164 | static int perf_pmu_commit_txn(struct pmu *pmu) |
| 5165 | { |
| 5166 | perf_pmu_enable(pmu); |
| 5167 | return 0; |
| 5168 | } |
| 5169 | |
| 5170 | static void perf_pmu_cancel_txn(struct pmu *pmu) |
| 5171 | { |
| 5172 | perf_pmu_enable(pmu); |
| 5173 | } |
| 5174 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 5175 | /* |
| 5176 | * Ensures all contexts with the same task_ctx_nr have the same |
| 5177 | * pmu_cpu_context too. |
| 5178 | */ |
| 5179 | static void *find_pmu_context(int ctxn) |
| 5180 | { |
| 5181 | struct pmu *pmu; |
| 5182 | |
| 5183 | if (ctxn < 0) |
| 5184 | return NULL; |
| 5185 | |
| 5186 | list_for_each_entry(pmu, &pmus, entry) { |
| 5187 | if (pmu->task_ctx_nr == ctxn) |
| 5188 | return pmu->pmu_cpu_context; |
| 5189 | } |
| 5190 | |
| 5191 | return NULL; |
| 5192 | } |
| 5193 | |
| 5194 | static void free_pmu_context(void * __percpu cpu_context) |
| 5195 | { |
| 5196 | struct pmu *pmu; |
| 5197 | |
| 5198 | mutex_lock(&pmus_lock); |
| 5199 | /* |
| 5200 | * Like a real lame refcount. |
| 5201 | */ |
| 5202 | list_for_each_entry(pmu, &pmus, entry) { |
| 5203 | if (pmu->pmu_cpu_context == cpu_context) |
| 5204 | goto out; |
| 5205 | } |
| 5206 | |
| 5207 | free_percpu(cpu_context); |
| 5208 | out: |
| 5209 | mutex_unlock(&pmus_lock); |
| 5210 | } |
| 5211 | |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5212 | int perf_pmu_register(struct pmu *pmu) |
| 5213 | { |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 5214 | int cpu, ret; |
Peter Zijlstra | 33696fc | 2010-06-14 08:49:00 +0200 | [diff] [blame] | 5215 | |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5216 | mutex_lock(&pmus_lock); |
Peter Zijlstra | 33696fc | 2010-06-14 08:49:00 +0200 | [diff] [blame] | 5217 | ret = -ENOMEM; |
| 5218 | pmu->pmu_disable_count = alloc_percpu(int); |
| 5219 | if (!pmu->pmu_disable_count) |
| 5220 | goto unlock; |
Peter Zijlstra | ad5133b | 2010-06-15 12:22:39 +0200 | [diff] [blame] | 5221 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 5222 | pmu->pmu_cpu_context = find_pmu_context(pmu->task_ctx_nr); |
| 5223 | if (pmu->pmu_cpu_context) |
| 5224 | goto got_cpu_context; |
| 5225 | |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 5226 | pmu->pmu_cpu_context = alloc_percpu(struct perf_cpu_context); |
| 5227 | if (!pmu->pmu_cpu_context) |
| 5228 | goto free_pdc; |
| 5229 | |
| 5230 | for_each_possible_cpu(cpu) { |
| 5231 | struct perf_cpu_context *cpuctx; |
| 5232 | |
| 5233 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); |
Peter Zijlstra | eb18447 | 2010-09-07 15:55:13 +0200 | [diff] [blame] | 5234 | __perf_event_init_context(&cpuctx->ctx); |
Peter Zijlstra | b04243e | 2010-09-17 11:28:48 +0200 | [diff] [blame] | 5235 | cpuctx->ctx.type = cpu_context; |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 5236 | cpuctx->ctx.pmu = pmu; |
Peter Zijlstra | e9d2b06 | 2010-09-17 11:28:50 +0200 | [diff] [blame] | 5237 | cpuctx->jiffies_interval = 1; |
| 5238 | INIT_LIST_HEAD(&cpuctx->rotation_list); |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 5239 | } |
| 5240 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 5241 | got_cpu_context: |
Peter Zijlstra | ad5133b | 2010-06-15 12:22:39 +0200 | [diff] [blame] | 5242 | if (!pmu->start_txn) { |
| 5243 | if (pmu->pmu_enable) { |
| 5244 | /* |
| 5245 | * If we have pmu_enable/pmu_disable calls, install |
| 5246 | * transaction stubs that use that to try and batch |
| 5247 | * hardware accesses. |
| 5248 | */ |
| 5249 | pmu->start_txn = perf_pmu_start_txn; |
| 5250 | pmu->commit_txn = perf_pmu_commit_txn; |
| 5251 | pmu->cancel_txn = perf_pmu_cancel_txn; |
| 5252 | } else { |
| 5253 | pmu->start_txn = perf_pmu_nop_void; |
| 5254 | pmu->commit_txn = perf_pmu_nop_int; |
| 5255 | pmu->cancel_txn = perf_pmu_nop_void; |
| 5256 | } |
| 5257 | } |
| 5258 | |
| 5259 | if (!pmu->pmu_enable) { |
| 5260 | pmu->pmu_enable = perf_pmu_nop_void; |
| 5261 | pmu->pmu_disable = perf_pmu_nop_void; |
| 5262 | } |
| 5263 | |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5264 | list_add_rcu(&pmu->entry, &pmus); |
Peter Zijlstra | 33696fc | 2010-06-14 08:49:00 +0200 | [diff] [blame] | 5265 | ret = 0; |
| 5266 | unlock: |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5267 | mutex_unlock(&pmus_lock); |
| 5268 | |
Peter Zijlstra | 33696fc | 2010-06-14 08:49:00 +0200 | [diff] [blame] | 5269 | return ret; |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 5270 | |
| 5271 | free_pdc: |
| 5272 | free_percpu(pmu->pmu_disable_count); |
| 5273 | goto unlock; |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5274 | } |
| 5275 | |
| 5276 | void perf_pmu_unregister(struct pmu *pmu) |
| 5277 | { |
| 5278 | mutex_lock(&pmus_lock); |
| 5279 | list_del_rcu(&pmu->entry); |
| 5280 | mutex_unlock(&pmus_lock); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5281 | |
| 5282 | /* |
Peter Zijlstra | cde8e88 | 2010-09-13 11:06:55 +0200 | [diff] [blame] | 5283 | * We dereference the pmu list under both SRCU and regular RCU, so |
| 5284 | * synchronize against both of those. |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5285 | */ |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5286 | synchronize_srcu(&pmus_srcu); |
Peter Zijlstra | cde8e88 | 2010-09-13 11:06:55 +0200 | [diff] [blame] | 5287 | synchronize_rcu(); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5288 | |
Peter Zijlstra | 33696fc | 2010-06-14 08:49:00 +0200 | [diff] [blame] | 5289 | free_percpu(pmu->pmu_disable_count); |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 5290 | free_pmu_context(pmu->pmu_cpu_context); |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5291 | } |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5292 | |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5293 | struct pmu *perf_init_event(struct perf_event *event) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5294 | { |
Peter Zijlstra | 51b0fe3 | 2010-06-11 13:35:57 +0200 | [diff] [blame] | 5295 | struct pmu *pmu = NULL; |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5296 | int idx; |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 5297 | |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5298 | idx = srcu_read_lock(&pmus_srcu); |
| 5299 | list_for_each_entry_rcu(pmu, &pmus, entry) { |
| 5300 | int ret = pmu->event_init(event); |
| 5301 | if (!ret) |
Peter Zijlstra | e5f4d33 | 2010-09-10 17:38:06 +0200 | [diff] [blame] | 5302 | goto unlock; |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 5303 | |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5304 | if (ret != -ENOENT) { |
| 5305 | pmu = ERR_PTR(ret); |
Peter Zijlstra | e5f4d33 | 2010-09-10 17:38:06 +0200 | [diff] [blame] | 5306 | goto unlock; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5307 | } |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5308 | } |
Peter Zijlstra | e5f4d33 | 2010-09-10 17:38:06 +0200 | [diff] [blame] | 5309 | pmu = ERR_PTR(-ENOENT); |
| 5310 | unlock: |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5311 | srcu_read_unlock(&pmus_srcu, idx); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5312 | |
| 5313 | return pmu; |
| 5314 | } |
| 5315 | |
| 5316 | /* |
| 5317 | * Allocate and initialize a event structure |
| 5318 | */ |
| 5319 | static struct perf_event * |
Peter Zijlstra | c3f00c7 | 2010-08-18 14:37:15 +0200 | [diff] [blame] | 5320 | perf_event_alloc(struct perf_event_attr *attr, int cpu, |
Peter Zijlstra | d580ff8 | 2010-10-14 17:43:23 +0200 | [diff] [blame] | 5321 | struct task_struct *task, |
| 5322 | struct perf_event *group_leader, |
| 5323 | struct perf_event *parent_event, |
| 5324 | perf_overflow_handler_t overflow_handler) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5325 | { |
Peter Zijlstra | 51b0fe3 | 2010-06-11 13:35:57 +0200 | [diff] [blame] | 5326 | struct pmu *pmu; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5327 | struct perf_event *event; |
| 5328 | struct hw_perf_event *hwc; |
| 5329 | long err; |
| 5330 | |
Peter Zijlstra | c3f00c7 | 2010-08-18 14:37:15 +0200 | [diff] [blame] | 5331 | event = kzalloc(sizeof(*event), GFP_KERNEL); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5332 | if (!event) |
| 5333 | return ERR_PTR(-ENOMEM); |
| 5334 | |
| 5335 | /* |
| 5336 | * Single events are their own group leaders, with an |
| 5337 | * empty sibling list: |
| 5338 | */ |
| 5339 | if (!group_leader) |
| 5340 | group_leader = event; |
| 5341 | |
| 5342 | mutex_init(&event->child_mutex); |
| 5343 | INIT_LIST_HEAD(&event->child_list); |
| 5344 | |
| 5345 | INIT_LIST_HEAD(&event->group_entry); |
| 5346 | INIT_LIST_HEAD(&event->event_entry); |
| 5347 | INIT_LIST_HEAD(&event->sibling_list); |
| 5348 | init_waitqueue_head(&event->waitq); |
Peter Zijlstra | e360adb | 2010-10-14 14:01:34 +0800 | [diff] [blame] | 5349 | init_irq_work(&event->pending, perf_pending_event); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5350 | |
| 5351 | mutex_init(&event->mmap_mutex); |
| 5352 | |
| 5353 | event->cpu = cpu; |
| 5354 | event->attr = *attr; |
| 5355 | event->group_leader = group_leader; |
| 5356 | event->pmu = NULL; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5357 | event->oncpu = -1; |
| 5358 | |
| 5359 | event->parent = parent_event; |
| 5360 | |
| 5361 | event->ns = get_pid_ns(current->nsproxy->pid_ns); |
| 5362 | event->id = atomic64_inc_return(&perf_event_id); |
| 5363 | |
| 5364 | event->state = PERF_EVENT_STATE_INACTIVE; |
| 5365 | |
Peter Zijlstra | d580ff8 | 2010-10-14 17:43:23 +0200 | [diff] [blame] | 5366 | if (task) { |
| 5367 | event->attach_state = PERF_ATTACH_TASK; |
| 5368 | #ifdef CONFIG_HAVE_HW_BREAKPOINT |
| 5369 | /* |
| 5370 | * hw_breakpoint is a bit difficult here.. |
| 5371 | */ |
| 5372 | if (attr->type == PERF_TYPE_BREAKPOINT) |
| 5373 | event->hw.bp_target = task; |
| 5374 | #endif |
| 5375 | } |
| 5376 | |
Frederic Weisbecker | b326e95 | 2009-12-05 09:44:31 +0100 | [diff] [blame] | 5377 | if (!overflow_handler && parent_event) |
| 5378 | overflow_handler = parent_event->overflow_handler; |
Frederic Weisbecker | 97eaf53 | 2009-10-18 15:33:50 +0200 | [diff] [blame] | 5379 | |
Frederic Weisbecker | b326e95 | 2009-12-05 09:44:31 +0100 | [diff] [blame] | 5380 | event->overflow_handler = overflow_handler; |
Frederic Weisbecker | 97eaf53 | 2009-10-18 15:33:50 +0200 | [diff] [blame] | 5381 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5382 | if (attr->disabled) |
| 5383 | event->state = PERF_EVENT_STATE_OFF; |
| 5384 | |
| 5385 | pmu = NULL; |
| 5386 | |
| 5387 | hwc = &event->hw; |
| 5388 | hwc->sample_period = attr->sample_period; |
| 5389 | if (attr->freq && attr->sample_freq) |
| 5390 | hwc->sample_period = 1; |
| 5391 | hwc->last_period = hwc->sample_period; |
| 5392 | |
Peter Zijlstra | e785059 | 2010-05-21 14:43:08 +0200 | [diff] [blame] | 5393 | local64_set(&hwc->period_left, hwc->sample_period); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5394 | |
| 5395 | /* |
| 5396 | * we currently do not support PERF_FORMAT_GROUP on inherited events |
| 5397 | */ |
| 5398 | if (attr->inherit && (attr->read_format & PERF_FORMAT_GROUP)) |
| 5399 | goto done; |
| 5400 | |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 5401 | pmu = perf_init_event(event); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5402 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5403 | done: |
| 5404 | err = 0; |
| 5405 | if (!pmu) |
| 5406 | err = -EINVAL; |
| 5407 | else if (IS_ERR(pmu)) |
| 5408 | err = PTR_ERR(pmu); |
| 5409 | |
| 5410 | if (err) { |
| 5411 | if (event->ns) |
| 5412 | put_pid_ns(event->ns); |
| 5413 | kfree(event); |
| 5414 | return ERR_PTR(err); |
| 5415 | } |
| 5416 | |
| 5417 | event->pmu = pmu; |
| 5418 | |
| 5419 | if (!event->parent) { |
Peter Zijlstra | 82cd6de | 2010-10-14 17:57:23 +0200 | [diff] [blame] | 5420 | if (event->attach_state & PERF_ATTACH_TASK) |
| 5421 | jump_label_inc(&perf_task_events); |
Eric B Munson | 3af9e85 | 2010-05-18 15:30:49 +0100 | [diff] [blame] | 5422 | if (event->attr.mmap || event->attr.mmap_data) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5423 | atomic_inc(&nr_mmap_events); |
| 5424 | if (event->attr.comm) |
| 5425 | atomic_inc(&nr_comm_events); |
| 5426 | if (event->attr.task) |
| 5427 | atomic_inc(&nr_task_events); |
Frederic Weisbecker | 927c7a9 | 2010-07-01 16:20:36 +0200 | [diff] [blame] | 5428 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) { |
| 5429 | err = get_callchain_buffers(); |
| 5430 | if (err) { |
| 5431 | free_event(event); |
| 5432 | return ERR_PTR(err); |
| 5433 | } |
| 5434 | } |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5435 | } |
| 5436 | |
| 5437 | return event; |
| 5438 | } |
| 5439 | |
| 5440 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
| 5441 | struct perf_event_attr *attr) |
| 5442 | { |
| 5443 | u32 size; |
| 5444 | int ret; |
| 5445 | |
| 5446 | if (!access_ok(VERIFY_WRITE, uattr, PERF_ATTR_SIZE_VER0)) |
| 5447 | return -EFAULT; |
| 5448 | |
| 5449 | /* |
| 5450 | * zero the full structure, so that a short copy will be nice. |
| 5451 | */ |
| 5452 | memset(attr, 0, sizeof(*attr)); |
| 5453 | |
| 5454 | ret = get_user(size, &uattr->size); |
| 5455 | if (ret) |
| 5456 | return ret; |
| 5457 | |
| 5458 | if (size > PAGE_SIZE) /* silly large */ |
| 5459 | goto err_size; |
| 5460 | |
| 5461 | if (!size) /* abi compat */ |
| 5462 | size = PERF_ATTR_SIZE_VER0; |
| 5463 | |
| 5464 | if (size < PERF_ATTR_SIZE_VER0) |
| 5465 | goto err_size; |
| 5466 | |
| 5467 | /* |
| 5468 | * If we're handed a bigger struct than we know of, |
| 5469 | * ensure all the unknown bits are 0 - i.e. new |
| 5470 | * user-space does not rely on any kernel feature |
| 5471 | * extensions we dont know about yet. |
| 5472 | */ |
| 5473 | if (size > sizeof(*attr)) { |
| 5474 | unsigned char __user *addr; |
| 5475 | unsigned char __user *end; |
| 5476 | unsigned char val; |
| 5477 | |
| 5478 | addr = (void __user *)uattr + sizeof(*attr); |
| 5479 | end = (void __user *)uattr + size; |
| 5480 | |
| 5481 | for (; addr < end; addr++) { |
| 5482 | ret = get_user(val, addr); |
| 5483 | if (ret) |
| 5484 | return ret; |
| 5485 | if (val) |
| 5486 | goto err_size; |
| 5487 | } |
| 5488 | size = sizeof(*attr); |
| 5489 | } |
| 5490 | |
| 5491 | ret = copy_from_user(attr, uattr, size); |
| 5492 | if (ret) |
| 5493 | return -EFAULT; |
| 5494 | |
| 5495 | /* |
| 5496 | * If the type exists, the corresponding creation will verify |
| 5497 | * the attr->config. |
| 5498 | */ |
| 5499 | if (attr->type >= PERF_TYPE_MAX) |
| 5500 | return -EINVAL; |
| 5501 | |
Mahesh Salgaonkar | cd75764 | 2010-01-30 10:25:18 +0530 | [diff] [blame] | 5502 | if (attr->__reserved_1) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5503 | return -EINVAL; |
| 5504 | |
| 5505 | if (attr->sample_type & ~(PERF_SAMPLE_MAX-1)) |
| 5506 | return -EINVAL; |
| 5507 | |
| 5508 | if (attr->read_format & ~(PERF_FORMAT_MAX-1)) |
| 5509 | return -EINVAL; |
| 5510 | |
| 5511 | out: |
| 5512 | return ret; |
| 5513 | |
| 5514 | err_size: |
| 5515 | put_user(sizeof(*attr), &uattr->size); |
| 5516 | ret = -E2BIG; |
| 5517 | goto out; |
| 5518 | } |
| 5519 | |
Peter Zijlstra | ac9721f | 2010-05-27 12:54:41 +0200 | [diff] [blame] | 5520 | static int |
| 5521 | perf_event_set_output(struct perf_event *event, struct perf_event *output_event) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5522 | { |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 5523 | struct perf_buffer *buffer = NULL, *old_buffer = NULL; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5524 | int ret = -EINVAL; |
| 5525 | |
Peter Zijlstra | ac9721f | 2010-05-27 12:54:41 +0200 | [diff] [blame] | 5526 | if (!output_event) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5527 | goto set; |
| 5528 | |
Peter Zijlstra | ac9721f | 2010-05-27 12:54:41 +0200 | [diff] [blame] | 5529 | /* don't allow circular references */ |
| 5530 | if (event == output_event) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5531 | goto out; |
| 5532 | |
Peter Zijlstra | 0f13930 | 2010-05-20 14:35:15 +0200 | [diff] [blame] | 5533 | /* |
| 5534 | * Don't allow cross-cpu buffers |
| 5535 | */ |
| 5536 | if (output_event->cpu != event->cpu) |
| 5537 | goto out; |
| 5538 | |
| 5539 | /* |
| 5540 | * If its not a per-cpu buffer, it must be the same task. |
| 5541 | */ |
| 5542 | if (output_event->cpu == -1 && output_event->ctx != event->ctx) |
| 5543 | goto out; |
| 5544 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5545 | set: |
| 5546 | mutex_lock(&event->mmap_mutex); |
Peter Zijlstra | ac9721f | 2010-05-27 12:54:41 +0200 | [diff] [blame] | 5547 | /* Can't redirect output if we've got an active mmap() */ |
| 5548 | if (atomic_read(&event->mmap_count)) |
| 5549 | goto unlock; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5550 | |
Peter Zijlstra | ac9721f | 2010-05-27 12:54:41 +0200 | [diff] [blame] | 5551 | if (output_event) { |
| 5552 | /* get the buffer we want to redirect to */ |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 5553 | buffer = perf_buffer_get(output_event); |
| 5554 | if (!buffer) |
Peter Zijlstra | ac9721f | 2010-05-27 12:54:41 +0200 | [diff] [blame] | 5555 | goto unlock; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5556 | } |
| 5557 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 5558 | old_buffer = event->buffer; |
| 5559 | rcu_assign_pointer(event->buffer, buffer); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5560 | ret = 0; |
Peter Zijlstra | ac9721f | 2010-05-27 12:54:41 +0200 | [diff] [blame] | 5561 | unlock: |
| 5562 | mutex_unlock(&event->mmap_mutex); |
| 5563 | |
Peter Zijlstra | ca5135e | 2010-05-28 19:33:23 +0200 | [diff] [blame] | 5564 | if (old_buffer) |
| 5565 | perf_buffer_put(old_buffer); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5566 | out: |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5567 | return ret; |
| 5568 | } |
| 5569 | |
| 5570 | /** |
| 5571 | * sys_perf_event_open - open a performance event, associate it to a task/cpu |
| 5572 | * |
| 5573 | * @attr_uptr: event_id type attributes for monitoring/sampling |
| 5574 | * @pid: target pid |
| 5575 | * @cpu: target cpu |
| 5576 | * @group_fd: group leader event fd |
| 5577 | */ |
| 5578 | SYSCALL_DEFINE5(perf_event_open, |
| 5579 | struct perf_event_attr __user *, attr_uptr, |
| 5580 | pid_t, pid, int, cpu, int, group_fd, unsigned long, flags) |
| 5581 | { |
Peter Zijlstra | b04243e | 2010-09-17 11:28:48 +0200 | [diff] [blame] | 5582 | struct perf_event *group_leader = NULL, *output_event = NULL; |
| 5583 | struct perf_event *event, *sibling; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5584 | struct perf_event_attr attr; |
| 5585 | struct perf_event_context *ctx; |
| 5586 | struct file *event_file = NULL; |
| 5587 | struct file *group_file = NULL; |
Matt Helsley | 38a81da | 2010-09-13 13:01:20 -0700 | [diff] [blame] | 5588 | struct task_struct *task = NULL; |
Peter Zijlstra | 89a1e18 | 2010-09-07 17:34:50 +0200 | [diff] [blame] | 5589 | struct pmu *pmu; |
Al Viro | ea635c6 | 2010-05-26 17:40:29 -0400 | [diff] [blame] | 5590 | int event_fd; |
Peter Zijlstra | b04243e | 2010-09-17 11:28:48 +0200 | [diff] [blame] | 5591 | int move_group = 0; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5592 | int fput_needed = 0; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5593 | int err; |
| 5594 | |
| 5595 | /* for future expandability... */ |
| 5596 | if (flags & ~(PERF_FLAG_FD_NO_GROUP | PERF_FLAG_FD_OUTPUT)) |
| 5597 | return -EINVAL; |
| 5598 | |
| 5599 | err = perf_copy_attr(attr_uptr, &attr); |
| 5600 | if (err) |
| 5601 | return err; |
| 5602 | |
| 5603 | if (!attr.exclude_kernel) { |
| 5604 | if (perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) |
| 5605 | return -EACCES; |
| 5606 | } |
| 5607 | |
| 5608 | if (attr.freq) { |
| 5609 | if (attr.sample_freq > sysctl_perf_event_sample_rate) |
| 5610 | return -EINVAL; |
| 5611 | } |
| 5612 | |
Al Viro | ea635c6 | 2010-05-26 17:40:29 -0400 | [diff] [blame] | 5613 | event_fd = get_unused_fd_flags(O_RDWR); |
| 5614 | if (event_fd < 0) |
| 5615 | return event_fd; |
| 5616 | |
Peter Zijlstra | ac9721f | 2010-05-27 12:54:41 +0200 | [diff] [blame] | 5617 | if (group_fd != -1) { |
| 5618 | group_leader = perf_fget_light(group_fd, &fput_needed); |
| 5619 | if (IS_ERR(group_leader)) { |
| 5620 | err = PTR_ERR(group_leader); |
Stephane Eranian | d14b12d | 2010-09-17 11:28:47 +0200 | [diff] [blame] | 5621 | goto err_fd; |
Peter Zijlstra | ac9721f | 2010-05-27 12:54:41 +0200 | [diff] [blame] | 5622 | } |
| 5623 | group_file = group_leader->filp; |
| 5624 | if (flags & PERF_FLAG_FD_OUTPUT) |
| 5625 | output_event = group_leader; |
| 5626 | if (flags & PERF_FLAG_FD_NO_GROUP) |
| 5627 | group_leader = NULL; |
| 5628 | } |
| 5629 | |
Peter Zijlstra | c6be5a5 | 2010-10-14 16:59:46 +0200 | [diff] [blame] | 5630 | if (pid != -1) { |
| 5631 | task = find_lively_task_by_vpid(pid); |
| 5632 | if (IS_ERR(task)) { |
| 5633 | err = PTR_ERR(task); |
| 5634 | goto err_group_fd; |
| 5635 | } |
| 5636 | } |
| 5637 | |
Peter Zijlstra | d580ff8 | 2010-10-14 17:43:23 +0200 | [diff] [blame] | 5638 | event = perf_event_alloc(&attr, cpu, task, group_leader, NULL, NULL); |
Stephane Eranian | d14b12d | 2010-09-17 11:28:47 +0200 | [diff] [blame] | 5639 | if (IS_ERR(event)) { |
| 5640 | err = PTR_ERR(event); |
Peter Zijlstra | c6be5a5 | 2010-10-14 16:59:46 +0200 | [diff] [blame] | 5641 | goto err_task; |
Stephane Eranian | d14b12d | 2010-09-17 11:28:47 +0200 | [diff] [blame] | 5642 | } |
| 5643 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5644 | /* |
Peter Zijlstra | 89a1e18 | 2010-09-07 17:34:50 +0200 | [diff] [blame] | 5645 | * Special case software events and allow them to be part of |
| 5646 | * any hardware group. |
| 5647 | */ |
| 5648 | pmu = event->pmu; |
Peter Zijlstra | b04243e | 2010-09-17 11:28:48 +0200 | [diff] [blame] | 5649 | |
| 5650 | if (group_leader && |
| 5651 | (is_software_event(event) != is_software_event(group_leader))) { |
| 5652 | if (is_software_event(event)) { |
| 5653 | /* |
| 5654 | * If event and group_leader are not both a software |
| 5655 | * event, and event is, then group leader is not. |
| 5656 | * |
| 5657 | * Allow the addition of software events to !software |
| 5658 | * groups, this is safe because software events never |
| 5659 | * fail to schedule. |
| 5660 | */ |
| 5661 | pmu = group_leader->pmu; |
| 5662 | } else if (is_software_event(group_leader) && |
| 5663 | (group_leader->group_flags & PERF_GROUP_SOFTWARE)) { |
| 5664 | /* |
| 5665 | * In case the group is a pure software group, and we |
| 5666 | * try to add a hardware event, move the whole group to |
| 5667 | * the hardware context. |
| 5668 | */ |
| 5669 | move_group = 1; |
| 5670 | } |
| 5671 | } |
Peter Zijlstra | 89a1e18 | 2010-09-07 17:34:50 +0200 | [diff] [blame] | 5672 | |
| 5673 | /* |
| 5674 | * Get the target context (task or percpu): |
| 5675 | */ |
Matt Helsley | 38a81da | 2010-09-13 13:01:20 -0700 | [diff] [blame] | 5676 | ctx = find_get_context(pmu, task, cpu); |
Peter Zijlstra | 89a1e18 | 2010-09-07 17:34:50 +0200 | [diff] [blame] | 5677 | if (IS_ERR(ctx)) { |
| 5678 | err = PTR_ERR(ctx); |
Peter Zijlstra | c6be5a5 | 2010-10-14 16:59:46 +0200 | [diff] [blame] | 5679 | goto err_alloc; |
Peter Zijlstra | 89a1e18 | 2010-09-07 17:34:50 +0200 | [diff] [blame] | 5680 | } |
| 5681 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5682 | /* |
| 5683 | * Look up the group leader (we will attach this event to it): |
| 5684 | */ |
Peter Zijlstra | ac9721f | 2010-05-27 12:54:41 +0200 | [diff] [blame] | 5685 | if (group_leader) { |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5686 | err = -EINVAL; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5687 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5688 | /* |
| 5689 | * Do not allow a recursive hierarchy (this new sibling |
| 5690 | * becoming part of another group-sibling): |
| 5691 | */ |
| 5692 | if (group_leader->group_leader != group_leader) |
Peter Zijlstra | c3f00c7 | 2010-08-18 14:37:15 +0200 | [diff] [blame] | 5693 | goto err_context; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5694 | /* |
| 5695 | * Do not allow to attach to a group in a different |
| 5696 | * task or CPU context: |
| 5697 | */ |
Peter Zijlstra | b04243e | 2010-09-17 11:28:48 +0200 | [diff] [blame] | 5698 | if (move_group) { |
| 5699 | if (group_leader->ctx->type != ctx->type) |
| 5700 | goto err_context; |
| 5701 | } else { |
| 5702 | if (group_leader->ctx != ctx) |
| 5703 | goto err_context; |
| 5704 | } |
| 5705 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5706 | /* |
| 5707 | * Only a group leader can be exclusive or pinned |
| 5708 | */ |
| 5709 | if (attr.exclusive || attr.pinned) |
Peter Zijlstra | c3f00c7 | 2010-08-18 14:37:15 +0200 | [diff] [blame] | 5710 | goto err_context; |
Peter Zijlstra | ac9721f | 2010-05-27 12:54:41 +0200 | [diff] [blame] | 5711 | } |
| 5712 | |
| 5713 | if (output_event) { |
| 5714 | err = perf_event_set_output(event, output_event); |
| 5715 | if (err) |
Peter Zijlstra | c3f00c7 | 2010-08-18 14:37:15 +0200 | [diff] [blame] | 5716 | goto err_context; |
Peter Zijlstra | ac9721f | 2010-05-27 12:54:41 +0200 | [diff] [blame] | 5717 | } |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5718 | |
Al Viro | ea635c6 | 2010-05-26 17:40:29 -0400 | [diff] [blame] | 5719 | event_file = anon_inode_getfile("[perf_event]", &perf_fops, event, O_RDWR); |
| 5720 | if (IS_ERR(event_file)) { |
| 5721 | err = PTR_ERR(event_file); |
Peter Zijlstra | c3f00c7 | 2010-08-18 14:37:15 +0200 | [diff] [blame] | 5722 | goto err_context; |
Al Viro | ea635c6 | 2010-05-26 17:40:29 -0400 | [diff] [blame] | 5723 | } |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5724 | |
Peter Zijlstra | b04243e | 2010-09-17 11:28:48 +0200 | [diff] [blame] | 5725 | if (move_group) { |
| 5726 | struct perf_event_context *gctx = group_leader->ctx; |
| 5727 | |
| 5728 | mutex_lock(&gctx->mutex); |
| 5729 | perf_event_remove_from_context(group_leader); |
| 5730 | list_for_each_entry(sibling, &group_leader->sibling_list, |
| 5731 | group_entry) { |
| 5732 | perf_event_remove_from_context(sibling); |
| 5733 | put_ctx(gctx); |
| 5734 | } |
| 5735 | mutex_unlock(&gctx->mutex); |
| 5736 | put_ctx(gctx); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5737 | } |
| 5738 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5739 | event->filp = event_file; |
| 5740 | WARN_ON_ONCE(ctx->parent_ctx); |
| 5741 | mutex_lock(&ctx->mutex); |
Peter Zijlstra | b04243e | 2010-09-17 11:28:48 +0200 | [diff] [blame] | 5742 | |
| 5743 | if (move_group) { |
| 5744 | perf_install_in_context(ctx, group_leader, cpu); |
| 5745 | get_ctx(ctx); |
| 5746 | list_for_each_entry(sibling, &group_leader->sibling_list, |
| 5747 | group_entry) { |
| 5748 | perf_install_in_context(ctx, sibling, cpu); |
| 5749 | get_ctx(ctx); |
| 5750 | } |
| 5751 | } |
| 5752 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5753 | perf_install_in_context(ctx, event, cpu); |
| 5754 | ++ctx->generation; |
| 5755 | mutex_unlock(&ctx->mutex); |
| 5756 | |
| 5757 | event->owner = current; |
Peter Zijlstra | 8882135 | 2010-11-09 19:01:43 +0100 | [diff] [blame] | 5758 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5759 | mutex_lock(¤t->perf_event_mutex); |
| 5760 | list_add_tail(&event->owner_entry, ¤t->perf_event_list); |
| 5761 | mutex_unlock(¤t->perf_event_mutex); |
| 5762 | |
Peter Zijlstra | 8a49542 | 2010-05-27 15:47:49 +0200 | [diff] [blame] | 5763 | /* |
Arnaldo Carvalho de Melo | c320c7b | 2010-10-20 12:50:11 -0200 | [diff] [blame] | 5764 | * Precalculate sample_data sizes |
| 5765 | */ |
| 5766 | perf_event__header_size(event); |
Arnaldo Carvalho de Melo | 6844c09 | 2010-12-03 16:36:35 -0200 | [diff] [blame^] | 5767 | perf_event__id_header_size(event); |
Arnaldo Carvalho de Melo | c320c7b | 2010-10-20 12:50:11 -0200 | [diff] [blame] | 5768 | |
| 5769 | /* |
Peter Zijlstra | 8a49542 | 2010-05-27 15:47:49 +0200 | [diff] [blame] | 5770 | * Drop the reference on the group_event after placing the |
| 5771 | * new event on the sibling_list. This ensures destruction |
| 5772 | * of the group leader will find the pointer to itself in |
| 5773 | * perf_group_detach(). |
| 5774 | */ |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5775 | fput_light(group_file, fput_needed); |
Al Viro | ea635c6 | 2010-05-26 17:40:29 -0400 | [diff] [blame] | 5776 | fd_install(event_fd, event_file); |
| 5777 | return event_fd; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5778 | |
Peter Zijlstra | c3f00c7 | 2010-08-18 14:37:15 +0200 | [diff] [blame] | 5779 | err_context: |
Al Viro | ea635c6 | 2010-05-26 17:40:29 -0400 | [diff] [blame] | 5780 | put_ctx(ctx); |
Peter Zijlstra | c6be5a5 | 2010-10-14 16:59:46 +0200 | [diff] [blame] | 5781 | err_alloc: |
| 5782 | free_event(event); |
Peter Zijlstra | e7d0bc0 | 2010-10-14 16:54:51 +0200 | [diff] [blame] | 5783 | err_task: |
| 5784 | if (task) |
| 5785 | put_task_struct(task); |
Peter Zijlstra | 89a1e18 | 2010-09-07 17:34:50 +0200 | [diff] [blame] | 5786 | err_group_fd: |
| 5787 | fput_light(group_file, fput_needed); |
Al Viro | ea635c6 | 2010-05-26 17:40:29 -0400 | [diff] [blame] | 5788 | err_fd: |
| 5789 | put_unused_fd(event_fd); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5790 | return err; |
| 5791 | } |
| 5792 | |
Arjan van de Ven | fb0459d | 2009-09-25 12:25:56 +0200 | [diff] [blame] | 5793 | /** |
| 5794 | * perf_event_create_kernel_counter |
| 5795 | * |
| 5796 | * @attr: attributes of the counter to create |
| 5797 | * @cpu: cpu in which the counter is bound |
Matt Helsley | 38a81da | 2010-09-13 13:01:20 -0700 | [diff] [blame] | 5798 | * @task: task to profile (NULL for percpu) |
Arjan van de Ven | fb0459d | 2009-09-25 12:25:56 +0200 | [diff] [blame] | 5799 | */ |
| 5800 | struct perf_event * |
| 5801 | perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, |
Matt Helsley | 38a81da | 2010-09-13 13:01:20 -0700 | [diff] [blame] | 5802 | struct task_struct *task, |
Frederic Weisbecker | b326e95 | 2009-12-05 09:44:31 +0100 | [diff] [blame] | 5803 | perf_overflow_handler_t overflow_handler) |
Arjan van de Ven | fb0459d | 2009-09-25 12:25:56 +0200 | [diff] [blame] | 5804 | { |
Arjan van de Ven | fb0459d | 2009-09-25 12:25:56 +0200 | [diff] [blame] | 5805 | struct perf_event_context *ctx; |
Peter Zijlstra | c3f00c7 | 2010-08-18 14:37:15 +0200 | [diff] [blame] | 5806 | struct perf_event *event; |
Arjan van de Ven | fb0459d | 2009-09-25 12:25:56 +0200 | [diff] [blame] | 5807 | int err; |
| 5808 | |
| 5809 | /* |
| 5810 | * Get the target context (task or percpu): |
| 5811 | */ |
| 5812 | |
Peter Zijlstra | d580ff8 | 2010-10-14 17:43:23 +0200 | [diff] [blame] | 5813 | event = perf_event_alloc(attr, cpu, task, NULL, NULL, overflow_handler); |
Frederic Weisbecker | c6567f6 | 2009-11-26 05:35:41 +0100 | [diff] [blame] | 5814 | if (IS_ERR(event)) { |
| 5815 | err = PTR_ERR(event); |
Peter Zijlstra | c3f00c7 | 2010-08-18 14:37:15 +0200 | [diff] [blame] | 5816 | goto err; |
| 5817 | } |
| 5818 | |
Matt Helsley | 38a81da | 2010-09-13 13:01:20 -0700 | [diff] [blame] | 5819 | ctx = find_get_context(event->pmu, task, cpu); |
Arjan van de Ven | fb0459d | 2009-09-25 12:25:56 +0200 | [diff] [blame] | 5820 | if (IS_ERR(ctx)) { |
| 5821 | err = PTR_ERR(ctx); |
Peter Zijlstra | c3f00c7 | 2010-08-18 14:37:15 +0200 | [diff] [blame] | 5822 | goto err_free; |
Frederic Weisbecker | c6567f6 | 2009-11-26 05:35:41 +0100 | [diff] [blame] | 5823 | } |
Arjan van de Ven | fb0459d | 2009-09-25 12:25:56 +0200 | [diff] [blame] | 5824 | |
| 5825 | event->filp = NULL; |
| 5826 | WARN_ON_ONCE(ctx->parent_ctx); |
| 5827 | mutex_lock(&ctx->mutex); |
| 5828 | perf_install_in_context(ctx, event, cpu); |
| 5829 | ++ctx->generation; |
| 5830 | mutex_unlock(&ctx->mutex); |
| 5831 | |
Arjan van de Ven | fb0459d | 2009-09-25 12:25:56 +0200 | [diff] [blame] | 5832 | return event; |
| 5833 | |
Peter Zijlstra | c3f00c7 | 2010-08-18 14:37:15 +0200 | [diff] [blame] | 5834 | err_free: |
| 5835 | free_event(event); |
| 5836 | err: |
Frederic Weisbecker | c6567f6 | 2009-11-26 05:35:41 +0100 | [diff] [blame] | 5837 | return ERR_PTR(err); |
Arjan van de Ven | fb0459d | 2009-09-25 12:25:56 +0200 | [diff] [blame] | 5838 | } |
| 5839 | EXPORT_SYMBOL_GPL(perf_event_create_kernel_counter); |
| 5840 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5841 | static void sync_child_event(struct perf_event *child_event, |
| 5842 | struct task_struct *child) |
| 5843 | { |
| 5844 | struct perf_event *parent_event = child_event->parent; |
| 5845 | u64 child_val; |
| 5846 | |
| 5847 | if (child_event->attr.inherit_stat) |
| 5848 | perf_event_read_event(child_event, child); |
| 5849 | |
Peter Zijlstra | b5e5879 | 2010-05-21 14:43:12 +0200 | [diff] [blame] | 5850 | child_val = perf_event_count(child_event); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5851 | |
| 5852 | /* |
| 5853 | * Add back the child's count to the parent's count: |
| 5854 | */ |
Peter Zijlstra | a6e6dea | 2010-05-21 14:27:58 +0200 | [diff] [blame] | 5855 | atomic64_add(child_val, &parent_event->child_count); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5856 | atomic64_add(child_event->total_time_enabled, |
| 5857 | &parent_event->child_total_time_enabled); |
| 5858 | atomic64_add(child_event->total_time_running, |
| 5859 | &parent_event->child_total_time_running); |
| 5860 | |
| 5861 | /* |
| 5862 | * Remove this event from the parent's list |
| 5863 | */ |
| 5864 | WARN_ON_ONCE(parent_event->ctx->parent_ctx); |
| 5865 | mutex_lock(&parent_event->child_mutex); |
| 5866 | list_del_init(&child_event->child_list); |
| 5867 | mutex_unlock(&parent_event->child_mutex); |
| 5868 | |
| 5869 | /* |
| 5870 | * Release the parent event, if this was the last |
| 5871 | * reference to it. |
| 5872 | */ |
| 5873 | fput(parent_event->filp); |
| 5874 | } |
| 5875 | |
| 5876 | static void |
| 5877 | __perf_event_exit_task(struct perf_event *child_event, |
| 5878 | struct perf_event_context *child_ctx, |
| 5879 | struct task_struct *child) |
| 5880 | { |
| 5881 | struct perf_event *parent_event; |
| 5882 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5883 | perf_event_remove_from_context(child_event); |
| 5884 | |
| 5885 | parent_event = child_event->parent; |
| 5886 | /* |
| 5887 | * It can happen that parent exits first, and has events |
| 5888 | * that are still around due to the child reference. These |
| 5889 | * events need to be zapped - but otherwise linger. |
| 5890 | */ |
| 5891 | if (parent_event) { |
| 5892 | sync_child_event(child_event, child); |
| 5893 | free_event(child_event); |
| 5894 | } |
| 5895 | } |
| 5896 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 5897 | static void perf_event_exit_task_context(struct task_struct *child, int ctxn) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5898 | { |
| 5899 | struct perf_event *child_event, *tmp; |
| 5900 | struct perf_event_context *child_ctx; |
| 5901 | unsigned long flags; |
| 5902 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 5903 | if (likely(!child->perf_event_ctxp[ctxn])) { |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5904 | perf_event_task(child, NULL, 0); |
| 5905 | return; |
| 5906 | } |
| 5907 | |
| 5908 | local_irq_save(flags); |
| 5909 | /* |
| 5910 | * We can't reschedule here because interrupts are disabled, |
| 5911 | * and either child is current or it is a task that can't be |
| 5912 | * scheduled, so we are now safe from rescheduling changing |
| 5913 | * our context. |
| 5914 | */ |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 5915 | child_ctx = child->perf_event_ctxp[ctxn]; |
Peter Zijlstra | 82cd6de | 2010-10-14 17:57:23 +0200 | [diff] [blame] | 5916 | task_ctx_sched_out(child_ctx, EVENT_ALL); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5917 | |
| 5918 | /* |
| 5919 | * Take the context lock here so that if find_get_context is |
| 5920 | * reading child->perf_event_ctxp, we wait until it has |
| 5921 | * incremented the context's refcount before we do put_ctx below. |
| 5922 | */ |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 5923 | raw_spin_lock(&child_ctx->lock); |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 5924 | child->perf_event_ctxp[ctxn] = NULL; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5925 | /* |
| 5926 | * If this context is a clone; unclone it so it can't get |
| 5927 | * swapped to another process while we're removing all |
| 5928 | * the events from it. |
| 5929 | */ |
| 5930 | unclone_ctx(child_ctx); |
Peter Zijlstra | 5e942bb | 2009-11-23 11:37:26 +0100 | [diff] [blame] | 5931 | update_context_time(child_ctx); |
Thomas Gleixner | e625cce1 | 2009-11-17 18:02:06 +0100 | [diff] [blame] | 5932 | raw_spin_unlock_irqrestore(&child_ctx->lock, flags); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5933 | |
| 5934 | /* |
| 5935 | * Report the task dead after unscheduling the events so that we |
| 5936 | * won't get any samples after PERF_RECORD_EXIT. We can however still |
| 5937 | * get a few PERF_RECORD_READ events. |
| 5938 | */ |
| 5939 | perf_event_task(child, child_ctx, 0); |
| 5940 | |
| 5941 | /* |
| 5942 | * We can recurse on the same lock type through: |
| 5943 | * |
| 5944 | * __perf_event_exit_task() |
| 5945 | * sync_child_event() |
| 5946 | * fput(parent_event->filp) |
| 5947 | * perf_release() |
| 5948 | * mutex_lock(&ctx->mutex) |
| 5949 | * |
| 5950 | * But since its the parent context it won't be the same instance. |
| 5951 | */ |
Peter Zijlstra | a0507c8 | 2010-05-06 15:42:53 +0200 | [diff] [blame] | 5952 | mutex_lock(&child_ctx->mutex); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5953 | |
| 5954 | again: |
Frederic Weisbecker | 889ff01 | 2010-01-09 20:04:47 +0100 | [diff] [blame] | 5955 | list_for_each_entry_safe(child_event, tmp, &child_ctx->pinned_groups, |
| 5956 | group_entry) |
| 5957 | __perf_event_exit_task(child_event, child_ctx, child); |
| 5958 | |
| 5959 | list_for_each_entry_safe(child_event, tmp, &child_ctx->flexible_groups, |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5960 | group_entry) |
| 5961 | __perf_event_exit_task(child_event, child_ctx, child); |
| 5962 | |
| 5963 | /* |
| 5964 | * If the last event was a group event, it will have appended all |
| 5965 | * its siblings to the list, but we obtained 'tmp' before that which |
| 5966 | * will still point to the list head terminating the iteration. |
| 5967 | */ |
Frederic Weisbecker | 889ff01 | 2010-01-09 20:04:47 +0100 | [diff] [blame] | 5968 | if (!list_empty(&child_ctx->pinned_groups) || |
| 5969 | !list_empty(&child_ctx->flexible_groups)) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 5970 | goto again; |
| 5971 | |
| 5972 | mutex_unlock(&child_ctx->mutex); |
| 5973 | |
| 5974 | put_ctx(child_ctx); |
| 5975 | } |
| 5976 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 5977 | /* |
| 5978 | * When a child task exits, feed back event values to parent events. |
| 5979 | */ |
| 5980 | void perf_event_exit_task(struct task_struct *child) |
| 5981 | { |
Peter Zijlstra | 8882135 | 2010-11-09 19:01:43 +0100 | [diff] [blame] | 5982 | struct perf_event *event, *tmp; |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 5983 | int ctxn; |
| 5984 | |
Peter Zijlstra | 8882135 | 2010-11-09 19:01:43 +0100 | [diff] [blame] | 5985 | mutex_lock(&child->perf_event_mutex); |
| 5986 | list_for_each_entry_safe(event, tmp, &child->perf_event_list, |
| 5987 | owner_entry) { |
| 5988 | list_del_init(&event->owner_entry); |
| 5989 | |
| 5990 | /* |
| 5991 | * Ensure the list deletion is visible before we clear |
| 5992 | * the owner, closes a race against perf_release() where |
| 5993 | * we need to serialize on the owner->perf_event_mutex. |
| 5994 | */ |
| 5995 | smp_wmb(); |
| 5996 | event->owner = NULL; |
| 5997 | } |
| 5998 | mutex_unlock(&child->perf_event_mutex); |
| 5999 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 6000 | for_each_task_context_nr(ctxn) |
| 6001 | perf_event_exit_task_context(child, ctxn); |
| 6002 | } |
| 6003 | |
Frederic Weisbecker | 889ff01 | 2010-01-09 20:04:47 +0100 | [diff] [blame] | 6004 | static void perf_free_event(struct perf_event *event, |
| 6005 | struct perf_event_context *ctx) |
| 6006 | { |
| 6007 | struct perf_event *parent = event->parent; |
| 6008 | |
| 6009 | if (WARN_ON_ONCE(!parent)) |
| 6010 | return; |
| 6011 | |
| 6012 | mutex_lock(&parent->child_mutex); |
| 6013 | list_del_init(&event->child_list); |
| 6014 | mutex_unlock(&parent->child_mutex); |
| 6015 | |
| 6016 | fput(parent->filp); |
| 6017 | |
Peter Zijlstra | 8a49542 | 2010-05-27 15:47:49 +0200 | [diff] [blame] | 6018 | perf_group_detach(event); |
Frederic Weisbecker | 889ff01 | 2010-01-09 20:04:47 +0100 | [diff] [blame] | 6019 | list_del_event(event, ctx); |
| 6020 | free_event(event); |
| 6021 | } |
| 6022 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6023 | /* |
| 6024 | * free an unexposed, unused context as created by inheritance by |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 6025 | * perf_event_init_task below, used by fork() in case of fail. |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6026 | */ |
| 6027 | void perf_event_free_task(struct task_struct *task) |
| 6028 | { |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 6029 | struct perf_event_context *ctx; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6030 | struct perf_event *event, *tmp; |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 6031 | int ctxn; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6032 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 6033 | for_each_task_context_nr(ctxn) { |
| 6034 | ctx = task->perf_event_ctxp[ctxn]; |
| 6035 | if (!ctx) |
| 6036 | continue; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6037 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 6038 | mutex_lock(&ctx->mutex); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6039 | again: |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 6040 | list_for_each_entry_safe(event, tmp, &ctx->pinned_groups, |
| 6041 | group_entry) |
| 6042 | perf_free_event(event, ctx); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6043 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 6044 | list_for_each_entry_safe(event, tmp, &ctx->flexible_groups, |
| 6045 | group_entry) |
| 6046 | perf_free_event(event, ctx); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6047 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 6048 | if (!list_empty(&ctx->pinned_groups) || |
| 6049 | !list_empty(&ctx->flexible_groups)) |
| 6050 | goto again; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6051 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 6052 | mutex_unlock(&ctx->mutex); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6053 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 6054 | put_ctx(ctx); |
| 6055 | } |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6056 | } |
| 6057 | |
Peter Zijlstra | 4e231c7 | 2010-09-09 21:01:59 +0200 | [diff] [blame] | 6058 | void perf_event_delayed_put(struct task_struct *task) |
| 6059 | { |
| 6060 | int ctxn; |
| 6061 | |
| 6062 | for_each_task_context_nr(ctxn) |
| 6063 | WARN_ON_ONCE(task->perf_event_ctxp[ctxn]); |
| 6064 | } |
| 6065 | |
Peter Zijlstra | 97dee4f | 2010-09-07 15:35:33 +0200 | [diff] [blame] | 6066 | /* |
| 6067 | * inherit a event from parent task to child task: |
| 6068 | */ |
| 6069 | static struct perf_event * |
| 6070 | inherit_event(struct perf_event *parent_event, |
| 6071 | struct task_struct *parent, |
| 6072 | struct perf_event_context *parent_ctx, |
| 6073 | struct task_struct *child, |
| 6074 | struct perf_event *group_leader, |
| 6075 | struct perf_event_context *child_ctx) |
| 6076 | { |
| 6077 | struct perf_event *child_event; |
Peter Zijlstra | cee010e | 2010-09-10 12:51:54 +0200 | [diff] [blame] | 6078 | unsigned long flags; |
Peter Zijlstra | 97dee4f | 2010-09-07 15:35:33 +0200 | [diff] [blame] | 6079 | |
| 6080 | /* |
| 6081 | * Instead of creating recursive hierarchies of events, |
| 6082 | * we link inherited events back to the original parent, |
| 6083 | * which has a filp for sure, which we use as the reference |
| 6084 | * count: |
| 6085 | */ |
| 6086 | if (parent_event->parent) |
| 6087 | parent_event = parent_event->parent; |
| 6088 | |
| 6089 | child_event = perf_event_alloc(&parent_event->attr, |
| 6090 | parent_event->cpu, |
Peter Zijlstra | d580ff8 | 2010-10-14 17:43:23 +0200 | [diff] [blame] | 6091 | child, |
Peter Zijlstra | 97dee4f | 2010-09-07 15:35:33 +0200 | [diff] [blame] | 6092 | group_leader, parent_event, |
| 6093 | NULL); |
| 6094 | if (IS_ERR(child_event)) |
| 6095 | return child_event; |
| 6096 | get_ctx(child_ctx); |
| 6097 | |
| 6098 | /* |
| 6099 | * Make the child state follow the state of the parent event, |
| 6100 | * not its attr.disabled bit. We hold the parent's mutex, |
| 6101 | * so we won't race with perf_event_{en, dis}able_family. |
| 6102 | */ |
| 6103 | if (parent_event->state >= PERF_EVENT_STATE_INACTIVE) |
| 6104 | child_event->state = PERF_EVENT_STATE_INACTIVE; |
| 6105 | else |
| 6106 | child_event->state = PERF_EVENT_STATE_OFF; |
| 6107 | |
| 6108 | if (parent_event->attr.freq) { |
| 6109 | u64 sample_period = parent_event->hw.sample_period; |
| 6110 | struct hw_perf_event *hwc = &child_event->hw; |
| 6111 | |
| 6112 | hwc->sample_period = sample_period; |
| 6113 | hwc->last_period = sample_period; |
| 6114 | |
| 6115 | local64_set(&hwc->period_left, sample_period); |
| 6116 | } |
| 6117 | |
| 6118 | child_event->ctx = child_ctx; |
| 6119 | child_event->overflow_handler = parent_event->overflow_handler; |
| 6120 | |
| 6121 | /* |
Thomas Gleixner | 614b678 | 2010-12-03 16:24:32 -0200 | [diff] [blame] | 6122 | * Precalculate sample_data sizes |
| 6123 | */ |
| 6124 | perf_event__header_size(child_event); |
Arnaldo Carvalho de Melo | 6844c09 | 2010-12-03 16:36:35 -0200 | [diff] [blame^] | 6125 | perf_event__id_header_size(child_event); |
Thomas Gleixner | 614b678 | 2010-12-03 16:24:32 -0200 | [diff] [blame] | 6126 | |
| 6127 | /* |
Peter Zijlstra | 97dee4f | 2010-09-07 15:35:33 +0200 | [diff] [blame] | 6128 | * Link it up in the child's context: |
| 6129 | */ |
Peter Zijlstra | cee010e | 2010-09-10 12:51:54 +0200 | [diff] [blame] | 6130 | raw_spin_lock_irqsave(&child_ctx->lock, flags); |
Peter Zijlstra | 97dee4f | 2010-09-07 15:35:33 +0200 | [diff] [blame] | 6131 | add_event_to_ctx(child_event, child_ctx); |
Peter Zijlstra | cee010e | 2010-09-10 12:51:54 +0200 | [diff] [blame] | 6132 | raw_spin_unlock_irqrestore(&child_ctx->lock, flags); |
Peter Zijlstra | 97dee4f | 2010-09-07 15:35:33 +0200 | [diff] [blame] | 6133 | |
| 6134 | /* |
| 6135 | * Get a reference to the parent filp - we will fput it |
| 6136 | * when the child event exits. This is safe to do because |
| 6137 | * we are in the parent and we know that the filp still |
| 6138 | * exists and has a nonzero count: |
| 6139 | */ |
| 6140 | atomic_long_inc(&parent_event->filp->f_count); |
| 6141 | |
| 6142 | /* |
| 6143 | * Link this into the parent event's child list |
| 6144 | */ |
| 6145 | WARN_ON_ONCE(parent_event->ctx->parent_ctx); |
| 6146 | mutex_lock(&parent_event->child_mutex); |
| 6147 | list_add_tail(&child_event->child_list, &parent_event->child_list); |
| 6148 | mutex_unlock(&parent_event->child_mutex); |
| 6149 | |
| 6150 | return child_event; |
| 6151 | } |
| 6152 | |
| 6153 | static int inherit_group(struct perf_event *parent_event, |
| 6154 | struct task_struct *parent, |
| 6155 | struct perf_event_context *parent_ctx, |
| 6156 | struct task_struct *child, |
| 6157 | struct perf_event_context *child_ctx) |
| 6158 | { |
| 6159 | struct perf_event *leader; |
| 6160 | struct perf_event *sub; |
| 6161 | struct perf_event *child_ctr; |
| 6162 | |
| 6163 | leader = inherit_event(parent_event, parent, parent_ctx, |
| 6164 | child, NULL, child_ctx); |
| 6165 | if (IS_ERR(leader)) |
| 6166 | return PTR_ERR(leader); |
| 6167 | list_for_each_entry(sub, &parent_event->sibling_list, group_entry) { |
| 6168 | child_ctr = inherit_event(sub, parent, parent_ctx, |
| 6169 | child, leader, child_ctx); |
| 6170 | if (IS_ERR(child_ctr)) |
| 6171 | return PTR_ERR(child_ctr); |
| 6172 | } |
| 6173 | return 0; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6174 | } |
| 6175 | |
Frederic Weisbecker | 889ff01 | 2010-01-09 20:04:47 +0100 | [diff] [blame] | 6176 | static int |
| 6177 | inherit_task_group(struct perf_event *event, struct task_struct *parent, |
| 6178 | struct perf_event_context *parent_ctx, |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 6179 | struct task_struct *child, int ctxn, |
Frederic Weisbecker | 889ff01 | 2010-01-09 20:04:47 +0100 | [diff] [blame] | 6180 | int *inherited_all) |
| 6181 | { |
| 6182 | int ret; |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 6183 | struct perf_event_context *child_ctx; |
Frederic Weisbecker | 889ff01 | 2010-01-09 20:04:47 +0100 | [diff] [blame] | 6184 | |
| 6185 | if (!event->attr.inherit) { |
| 6186 | *inherited_all = 0; |
| 6187 | return 0; |
| 6188 | } |
| 6189 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 6190 | child_ctx = child->perf_event_ctxp[ctxn]; |
Frederic Weisbecker | 889ff01 | 2010-01-09 20:04:47 +0100 | [diff] [blame] | 6191 | if (!child_ctx) { |
| 6192 | /* |
| 6193 | * This is executed from the parent task context, so |
| 6194 | * inherit events that have been marked for cloning. |
| 6195 | * First allocate and initialize a context for the |
| 6196 | * child. |
| 6197 | */ |
| 6198 | |
Peter Zijlstra | eb18447 | 2010-09-07 15:55:13 +0200 | [diff] [blame] | 6199 | child_ctx = alloc_perf_context(event->pmu, child); |
Frederic Weisbecker | 889ff01 | 2010-01-09 20:04:47 +0100 | [diff] [blame] | 6200 | if (!child_ctx) |
| 6201 | return -ENOMEM; |
| 6202 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 6203 | child->perf_event_ctxp[ctxn] = child_ctx; |
Frederic Weisbecker | 889ff01 | 2010-01-09 20:04:47 +0100 | [diff] [blame] | 6204 | } |
| 6205 | |
| 6206 | ret = inherit_group(event, parent, parent_ctx, |
| 6207 | child, child_ctx); |
| 6208 | |
| 6209 | if (ret) |
| 6210 | *inherited_all = 0; |
| 6211 | |
| 6212 | return ret; |
| 6213 | } |
| 6214 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6215 | /* |
| 6216 | * Initialize the perf_event context in task_struct |
| 6217 | */ |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 6218 | int perf_event_init_context(struct task_struct *child, int ctxn) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6219 | { |
Frederic Weisbecker | 889ff01 | 2010-01-09 20:04:47 +0100 | [diff] [blame] | 6220 | struct perf_event_context *child_ctx, *parent_ctx; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6221 | struct perf_event_context *cloned_ctx; |
| 6222 | struct perf_event *event; |
| 6223 | struct task_struct *parent = current; |
| 6224 | int inherited_all = 1; |
Thomas Gleixner | dddd337 | 2010-11-24 10:05:55 +0100 | [diff] [blame] | 6225 | unsigned long flags; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6226 | int ret = 0; |
| 6227 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 6228 | child->perf_event_ctxp[ctxn] = NULL; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6229 | |
| 6230 | mutex_init(&child->perf_event_mutex); |
| 6231 | INIT_LIST_HEAD(&child->perf_event_list); |
| 6232 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 6233 | if (likely(!parent->perf_event_ctxp[ctxn])) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6234 | return 0; |
| 6235 | |
| 6236 | /* |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6237 | * If the parent's context is a clone, pin it so it won't get |
| 6238 | * swapped under us. |
| 6239 | */ |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 6240 | parent_ctx = perf_pin_task_context(parent, ctxn); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6241 | |
| 6242 | /* |
| 6243 | * No need to check if parent_ctx != NULL here; since we saw |
| 6244 | * it non-NULL earlier, the only reason for it to become NULL |
| 6245 | * is if we exit, and since we're currently in the middle of |
| 6246 | * a fork we can't be exiting at the same time. |
| 6247 | */ |
| 6248 | |
| 6249 | /* |
| 6250 | * Lock the parent list. No need to lock the child - not PID |
| 6251 | * hashed yet and not running, so nobody can access it. |
| 6252 | */ |
| 6253 | mutex_lock(&parent_ctx->mutex); |
| 6254 | |
| 6255 | /* |
| 6256 | * We dont have to disable NMIs - we are only looking at |
| 6257 | * the list, not manipulating it: |
| 6258 | */ |
Frederic Weisbecker | 889ff01 | 2010-01-09 20:04:47 +0100 | [diff] [blame] | 6259 | list_for_each_entry(event, &parent_ctx->pinned_groups, group_entry) { |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 6260 | ret = inherit_task_group(event, parent, parent_ctx, |
| 6261 | child, ctxn, &inherited_all); |
Frederic Weisbecker | 889ff01 | 2010-01-09 20:04:47 +0100 | [diff] [blame] | 6262 | if (ret) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6263 | break; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6264 | } |
| 6265 | |
Thomas Gleixner | dddd337 | 2010-11-24 10:05:55 +0100 | [diff] [blame] | 6266 | /* |
| 6267 | * We can't hold ctx->lock when iterating the ->flexible_group list due |
| 6268 | * to allocations, but we need to prevent rotation because |
| 6269 | * rotate_ctx() will change the list from interrupt context. |
| 6270 | */ |
| 6271 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); |
| 6272 | parent_ctx->rotate_disable = 1; |
| 6273 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); |
| 6274 | |
Frederic Weisbecker | 889ff01 | 2010-01-09 20:04:47 +0100 | [diff] [blame] | 6275 | list_for_each_entry(event, &parent_ctx->flexible_groups, group_entry) { |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 6276 | ret = inherit_task_group(event, parent, parent_ctx, |
| 6277 | child, ctxn, &inherited_all); |
Frederic Weisbecker | 889ff01 | 2010-01-09 20:04:47 +0100 | [diff] [blame] | 6278 | if (ret) |
| 6279 | break; |
| 6280 | } |
| 6281 | |
Thomas Gleixner | dddd337 | 2010-11-24 10:05:55 +0100 | [diff] [blame] | 6282 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); |
| 6283 | parent_ctx->rotate_disable = 0; |
| 6284 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); |
| 6285 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 6286 | child_ctx = child->perf_event_ctxp[ctxn]; |
Frederic Weisbecker | 889ff01 | 2010-01-09 20:04:47 +0100 | [diff] [blame] | 6287 | |
Peter Zijlstra | 05cbaa2 | 2009-12-30 16:00:35 +0100 | [diff] [blame] | 6288 | if (child_ctx && inherited_all) { |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6289 | /* |
| 6290 | * Mark the child context as a clone of the parent |
| 6291 | * context, or of whatever the parent is a clone of. |
| 6292 | * Note that if the parent is a clone, it could get |
| 6293 | * uncloned at any point, but that doesn't matter |
| 6294 | * because the list of events and the generation |
| 6295 | * count can't have changed since we took the mutex. |
| 6296 | */ |
| 6297 | cloned_ctx = rcu_dereference(parent_ctx->parent_ctx); |
| 6298 | if (cloned_ctx) { |
| 6299 | child_ctx->parent_ctx = cloned_ctx; |
| 6300 | child_ctx->parent_gen = parent_ctx->parent_gen; |
| 6301 | } else { |
| 6302 | child_ctx->parent_ctx = parent_ctx; |
| 6303 | child_ctx->parent_gen = parent_ctx->generation; |
| 6304 | } |
| 6305 | get_ctx(child_ctx->parent_ctx); |
| 6306 | } |
| 6307 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6308 | mutex_unlock(&parent_ctx->mutex); |
| 6309 | |
| 6310 | perf_unpin_context(parent_ctx); |
| 6311 | |
| 6312 | return ret; |
| 6313 | } |
| 6314 | |
Peter Zijlstra | 8dc85d5 | 2010-09-02 16:50:03 +0200 | [diff] [blame] | 6315 | /* |
| 6316 | * Initialize the perf_event context in task_struct |
| 6317 | */ |
| 6318 | int perf_event_init_task(struct task_struct *child) |
| 6319 | { |
| 6320 | int ctxn, ret; |
| 6321 | |
| 6322 | for_each_task_context_nr(ctxn) { |
| 6323 | ret = perf_event_init_context(child, ctxn); |
| 6324 | if (ret) |
| 6325 | return ret; |
| 6326 | } |
| 6327 | |
| 6328 | return 0; |
| 6329 | } |
| 6330 | |
Paul Mackerras | 220b140 | 2010-03-10 20:45:52 +1100 | [diff] [blame] | 6331 | static void __init perf_event_init_all_cpus(void) |
| 6332 | { |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 6333 | struct swevent_htable *swhash; |
Paul Mackerras | 220b140 | 2010-03-10 20:45:52 +1100 | [diff] [blame] | 6334 | int cpu; |
Paul Mackerras | 220b140 | 2010-03-10 20:45:52 +1100 | [diff] [blame] | 6335 | |
| 6336 | for_each_possible_cpu(cpu) { |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 6337 | swhash = &per_cpu(swevent_htable, cpu); |
| 6338 | mutex_init(&swhash->hlist_mutex); |
Peter Zijlstra | e9d2b06 | 2010-09-17 11:28:50 +0200 | [diff] [blame] | 6339 | INIT_LIST_HEAD(&per_cpu(rotation_list, cpu)); |
Paul Mackerras | 220b140 | 2010-03-10 20:45:52 +1100 | [diff] [blame] | 6340 | } |
| 6341 | } |
| 6342 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6343 | static void __cpuinit perf_event_init_cpu(int cpu) |
| 6344 | { |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 6345 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6346 | |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 6347 | mutex_lock(&swhash->hlist_mutex); |
| 6348 | if (swhash->hlist_refcount > 0) { |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 6349 | struct swevent_hlist *hlist; |
| 6350 | |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 6351 | hlist = kzalloc_node(sizeof(*hlist), GFP_KERNEL, cpu_to_node(cpu)); |
| 6352 | WARN_ON(!hlist); |
| 6353 | rcu_assign_pointer(swhash->swevent_hlist, hlist); |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 6354 | } |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 6355 | mutex_unlock(&swhash->hlist_mutex); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6356 | } |
| 6357 | |
| 6358 | #ifdef CONFIG_HOTPLUG_CPU |
Peter Zijlstra | e9d2b06 | 2010-09-17 11:28:50 +0200 | [diff] [blame] | 6359 | static void perf_pmu_rotate_stop(struct pmu *pmu) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6360 | { |
Peter Zijlstra | e9d2b06 | 2010-09-17 11:28:50 +0200 | [diff] [blame] | 6361 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
| 6362 | |
| 6363 | WARN_ON(!irqs_disabled()); |
| 6364 | |
| 6365 | list_del_init(&cpuctx->rotation_list); |
| 6366 | } |
| 6367 | |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 6368 | static void __perf_event_exit_context(void *__info) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6369 | { |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 6370 | struct perf_event_context *ctx = __info; |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6371 | struct perf_event *event, *tmp; |
| 6372 | |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 6373 | perf_pmu_rotate_stop(ctx->pmu); |
Peter Zijlstra | b5ab4cd | 2010-09-06 16:32:21 +0200 | [diff] [blame] | 6374 | |
Frederic Weisbecker | 889ff01 | 2010-01-09 20:04:47 +0100 | [diff] [blame] | 6375 | list_for_each_entry_safe(event, tmp, &ctx->pinned_groups, group_entry) |
| 6376 | __perf_event_remove_from_context(event); |
| 6377 | list_for_each_entry_safe(event, tmp, &ctx->flexible_groups, group_entry) |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6378 | __perf_event_remove_from_context(event); |
| 6379 | } |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 6380 | |
| 6381 | static void perf_event_exit_cpu_context(int cpu) |
| 6382 | { |
| 6383 | struct perf_event_context *ctx; |
| 6384 | struct pmu *pmu; |
| 6385 | int idx; |
| 6386 | |
| 6387 | idx = srcu_read_lock(&pmus_srcu); |
| 6388 | list_for_each_entry_rcu(pmu, &pmus, entry) { |
Peter Zijlstra | 917bdd1 | 2010-09-17 11:28:49 +0200 | [diff] [blame] | 6389 | ctx = &per_cpu_ptr(pmu->pmu_cpu_context, cpu)->ctx; |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 6390 | |
| 6391 | mutex_lock(&ctx->mutex); |
| 6392 | smp_call_function_single(cpu, __perf_event_exit_context, ctx, 1); |
| 6393 | mutex_unlock(&ctx->mutex); |
| 6394 | } |
| 6395 | srcu_read_unlock(&pmus_srcu, idx); |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 6396 | } |
| 6397 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6398 | static void perf_event_exit_cpu(int cpu) |
| 6399 | { |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 6400 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6401 | |
Peter Zijlstra | b28ab83 | 2010-09-06 14:48:15 +0200 | [diff] [blame] | 6402 | mutex_lock(&swhash->hlist_mutex); |
| 6403 | swevent_hlist_release(swhash); |
| 6404 | mutex_unlock(&swhash->hlist_mutex); |
Frederic Weisbecker | 76e1d90 | 2010-04-05 15:35:57 +0200 | [diff] [blame] | 6405 | |
Peter Zijlstra | 108b02c | 2010-09-06 14:32:03 +0200 | [diff] [blame] | 6406 | perf_event_exit_cpu_context(cpu); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6407 | } |
| 6408 | #else |
| 6409 | static inline void perf_event_exit_cpu(int cpu) { } |
| 6410 | #endif |
| 6411 | |
| 6412 | static int __cpuinit |
| 6413 | perf_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu) |
| 6414 | { |
| 6415 | unsigned int cpu = (long)hcpu; |
| 6416 | |
Peter Zijlstra | 5e11637 | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 6417 | switch (action & ~CPU_TASKS_FROZEN) { |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6418 | |
| 6419 | case CPU_UP_PREPARE: |
Peter Zijlstra | 5e11637 | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 6420 | case CPU_DOWN_FAILED: |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6421 | perf_event_init_cpu(cpu); |
| 6422 | break; |
| 6423 | |
Peter Zijlstra | 5e11637 | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 6424 | case CPU_UP_CANCELED: |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6425 | case CPU_DOWN_PREPARE: |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6426 | perf_event_exit_cpu(cpu); |
| 6427 | break; |
| 6428 | |
| 6429 | default: |
| 6430 | break; |
| 6431 | } |
| 6432 | |
| 6433 | return NOTIFY_OK; |
| 6434 | } |
| 6435 | |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6436 | void __init perf_event_init(void) |
| 6437 | { |
Jason Wessel | 3c502e7 | 2010-11-04 17:33:01 -0500 | [diff] [blame] | 6438 | int ret; |
| 6439 | |
Paul Mackerras | 220b140 | 2010-03-10 20:45:52 +1100 | [diff] [blame] | 6440 | perf_event_init_all_cpus(); |
Peter Zijlstra | b0a873e | 2010-06-11 13:35:08 +0200 | [diff] [blame] | 6441 | init_srcu_struct(&pmus_srcu); |
| 6442 | perf_pmu_register(&perf_swevent); |
| 6443 | perf_pmu_register(&perf_cpu_clock); |
| 6444 | perf_pmu_register(&perf_task_clock); |
| 6445 | perf_tp_register(); |
| 6446 | perf_cpu_notifier(perf_cpu_notify); |
Jason Wessel | 3c502e7 | 2010-11-04 17:33:01 -0500 | [diff] [blame] | 6447 | |
| 6448 | ret = init_hw_breakpoint(); |
| 6449 | WARN(ret, "hw_breakpoint initialization failed with: %d", ret); |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 6450 | } |