blob: f3989ceb5cd5aa7cbfae069015e8d915d6eb4c59 [file] [log] [blame]
Steven Rostedtb77e38a2009-02-24 10:21:36 -05001/*
2 * event tracer
3 *
4 * Copyright (C) 2008 Red Hat Inc, Steven Rostedt <srostedt@redhat.com>
5 *
Steven Rostedt981d0812009-03-02 13:53:59 -05006 * - Added format output of fields of the trace point.
7 * This was based off of work by Tom Zanussi <tzanussi@gmail.com>.
8 *
Steven Rostedtb77e38a2009-02-24 10:21:36 -05009 */
10
Steven Rostedte6187002009-04-15 13:36:40 -040011#include <linux/workqueue.h>
12#include <linux/spinlock.h>
13#include <linux/kthread.h>
Steven Rostedtb77e38a2009-02-24 10:21:36 -050014#include <linux/debugfs.h>
15#include <linux/uaccess.h>
16#include <linux/module.h>
17#include <linux/ctype.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090018#include <linux/slab.h>
Steven Rostedte6187002009-04-15 13:36:40 -040019#include <linux/delay.h>
Steven Rostedtb77e38a2009-02-24 10:21:36 -050020
Li Zefan020e5f82009-07-01 10:47:05 +080021#include <asm/setup.h>
22
Steven Rostedt91729ef92009-03-02 15:03:01 -050023#include "trace_output.h"
Steven Rostedtb77e38a2009-02-24 10:21:36 -050024
Steven Rostedt4e5292e2009-09-12 19:26:21 -040025#undef TRACE_SYSTEM
Steven Rostedtb628b3e2009-02-27 23:32:58 -050026#define TRACE_SYSTEM "TRACE_SYSTEM"
27
Li Zefan20c89282009-05-06 10:33:45 +080028DEFINE_MUTEX(event_mutex);
Steven Rostedt11a241a2009-03-02 11:49:04 -050029
Steven Rostedt04295782010-11-12 22:32:11 -050030DEFINE_MUTEX(event_storage_mutex);
31EXPORT_SYMBOL_GPL(event_storage_mutex);
32
33char event_storage[EVENT_STORAGE_SIZE];
34EXPORT_SYMBOL_GPL(event_storage);
35
Steven Rostedta59fd602009-04-10 13:52:20 -040036LIST_HEAD(ftrace_events);
zhangwei(Jovi)b3a8c6f2013-03-11 15:13:42 +080037static LIST_HEAD(ftrace_common_fields);
Steven Rostedta59fd602009-04-10 13:52:20 -040038
Steven Rostedtd1a29142013-02-27 20:23:57 -050039#define GFP_TRACE (GFP_KERNEL | __GFP_ZERO)
40
41static struct kmem_cache *field_cachep;
42static struct kmem_cache *file_cachep;
43
Steven Rostedt6e94a782013-06-27 10:58:31 -040044#define SYSTEM_FL_FREE_NAME (1 << 31)
45
46static inline int system_refcount(struct event_subsystem *system)
47{
48 return system->ref_count & ~SYSTEM_FL_FREE_NAME;
49}
50
51static int system_refcount_inc(struct event_subsystem *system)
52{
53 return (system->ref_count++) & ~SYSTEM_FL_FREE_NAME;
54}
55
56static int system_refcount_dec(struct event_subsystem *system)
57{
58 return (--system->ref_count) & ~SYSTEM_FL_FREE_NAME;
59}
60
Steven Rostedtae63b312012-05-03 23:09:03 -040061/* Double loops, do not use break, only goto's work */
62#define do_for_each_event_file(tr, file) \
63 list_for_each_entry(tr, &ftrace_trace_arrays, list) { \
64 list_for_each_entry(file, &tr->events, list)
65
66#define do_for_each_event_file_safe(tr, file) \
67 list_for_each_entry(tr, &ftrace_trace_arrays, list) { \
68 struct ftrace_event_file *___n; \
69 list_for_each_entry_safe(file, ___n, &tr->events, list)
70
71#define while_for_each_event_file() \
72 }
73
zhangwei(Jovi)b3a8c6f2013-03-11 15:13:42 +080074static struct list_head *
Steven Rostedt2e33af02010-04-22 10:35:55 -040075trace_get_fields(struct ftrace_event_call *event_call)
76{
77 if (!event_call->class->get_fields)
78 return &event_call->class->fields;
79 return event_call->class->get_fields(event_call);
80}
81
zhangwei(Jovi)b3a8c6f2013-03-11 15:13:42 +080082static struct ftrace_event_field *
83__find_event_field(struct list_head *head, char *name)
84{
85 struct ftrace_event_field *field;
86
87 list_for_each_entry(field, head, link) {
88 if (!strcmp(field->name, name))
89 return field;
90 }
91
92 return NULL;
93}
94
95struct ftrace_event_field *
96trace_find_event_field(struct ftrace_event_call *call, char *name)
97{
98 struct ftrace_event_field *field;
99 struct list_head *head;
100
101 field = __find_event_field(&ftrace_common_fields, name);
102 if (field)
103 return field;
104
105 head = trace_get_fields(call);
106 return __find_event_field(head, name);
107}
108
Li Zefan8728fe52010-05-24 16:22:49 +0800109static int __trace_define_field(struct list_head *head, const char *type,
110 const char *name, int offset, int size,
111 int is_signed, int filter_type)
Tom Zanussicf027f62009-03-22 03:30:39 -0500112{
113 struct ftrace_event_field *field;
114
Steven Rostedtd1a29142013-02-27 20:23:57 -0500115 field = kmem_cache_alloc(field_cachep, GFP_TRACE);
Tom Zanussicf027f62009-03-22 03:30:39 -0500116 if (!field)
Namhyung Kimaaf6ac02013-06-07 15:07:48 +0900117 return -ENOMEM;
Ingo Molnarfe9f57f2009-03-22 18:41:59 +0100118
Steven Rostedt92edca02013-02-27 20:41:37 -0500119 field->name = name;
120 field->type = type;
Ingo Molnarfe9f57f2009-03-22 18:41:59 +0100121
Li Zefan43b51ea2009-08-07 10:33:22 +0800122 if (filter_type == FILTER_OTHER)
123 field->filter_type = filter_assign_type(type);
124 else
125 field->filter_type = filter_type;
126
Tom Zanussicf027f62009-03-22 03:30:39 -0500127 field->offset = offset;
128 field->size = size;
Tom Zanussia118e4d2009-04-28 03:04:53 -0500129 field->is_signed = is_signed;
Li Zefanaa38e9f2009-08-07 10:33:02 +0800130
Steven Rostedt2e33af02010-04-22 10:35:55 -0400131 list_add(&field->link, head);
Tom Zanussicf027f62009-03-22 03:30:39 -0500132
133 return 0;
Tom Zanussicf027f62009-03-22 03:30:39 -0500134}
Li Zefan8728fe52010-05-24 16:22:49 +0800135
136int trace_define_field(struct ftrace_event_call *call, const char *type,
137 const char *name, int offset, int size, int is_signed,
138 int filter_type)
139{
140 struct list_head *head;
141
142 if (WARN_ON(!call->class))
143 return 0;
144
145 head = trace_get_fields(call);
146 return __trace_define_field(head, type, name, offset, size,
147 is_signed, filter_type);
148}
Steven Rostedt17c873e2009-04-10 18:12:50 -0400149EXPORT_SYMBOL_GPL(trace_define_field);
Tom Zanussicf027f62009-03-22 03:30:39 -0500150
Li Zefane647d6b2009-08-19 15:54:32 +0800151#define __common_field(type, item) \
Li Zefan8728fe52010-05-24 16:22:49 +0800152 ret = __trace_define_field(&ftrace_common_fields, #type, \
153 "common_" #item, \
154 offsetof(typeof(ent), item), \
155 sizeof(ent.item), \
156 is_signed_type(type), FILTER_OTHER); \
Li Zefane647d6b2009-08-19 15:54:32 +0800157 if (ret) \
158 return ret;
159
Li Zefan8728fe52010-05-24 16:22:49 +0800160static int trace_define_common_fields(void)
Li Zefane647d6b2009-08-19 15:54:32 +0800161{
162 int ret;
163 struct trace_entry ent;
164
165 __common_field(unsigned short, type);
166 __common_field(unsigned char, flags);
167 __common_field(unsigned char, preempt_count);
168 __common_field(int, pid);
Li Zefane647d6b2009-08-19 15:54:32 +0800169
170 return ret;
171}
172
zhangwei(Jovi)ad7067c2013-03-11 15:13:46 +0800173static void trace_destroy_fields(struct ftrace_event_call *call)
Li Zefan2df75e42009-05-06 10:33:04 +0800174{
175 struct ftrace_event_field *field, *next;
Steven Rostedt2e33af02010-04-22 10:35:55 -0400176 struct list_head *head;
Li Zefan2df75e42009-05-06 10:33:04 +0800177
Steven Rostedt2e33af02010-04-22 10:35:55 -0400178 head = trace_get_fields(call);
179 list_for_each_entry_safe(field, next, head, link) {
Li Zefan2df75e42009-05-06 10:33:04 +0800180 list_del(&field->link);
Steven Rostedtd1a29142013-02-27 20:23:57 -0500181 kmem_cache_free(field_cachep, field);
Li Zefan2df75e42009-05-06 10:33:04 +0800182 }
183}
184
Li Zefan87d9b4e2009-12-08 11:14:20 +0800185int trace_event_raw_init(struct ftrace_event_call *call)
186{
187 int id;
188
Steven Rostedt80decc72010-04-23 10:00:22 -0400189 id = register_ftrace_event(&call->event);
Li Zefan87d9b4e2009-12-08 11:14:20 +0800190 if (!id)
191 return -ENODEV;
Li Zefan87d9b4e2009-12-08 11:14:20 +0800192
193 return 0;
194}
195EXPORT_SYMBOL_GPL(trace_event_raw_init);
196
Jiri Olsaceec0b62012-02-15 15:51:49 +0100197int ftrace_event_reg(struct ftrace_event_call *call,
198 enum trace_reg type, void *data)
Steven Rostedta1d0ce82010-06-08 11:22:06 -0400199{
Steven Rostedtae63b312012-05-03 23:09:03 -0400200 struct ftrace_event_file *file = data;
201
Steven Rostedta1d0ce82010-06-08 11:22:06 -0400202 switch (type) {
203 case TRACE_REG_REGISTER:
204 return tracepoint_probe_register(call->name,
205 call->class->probe,
Steven Rostedtae63b312012-05-03 23:09:03 -0400206 file);
Steven Rostedta1d0ce82010-06-08 11:22:06 -0400207 case TRACE_REG_UNREGISTER:
208 tracepoint_probe_unregister(call->name,
209 call->class->probe,
Steven Rostedtae63b312012-05-03 23:09:03 -0400210 file);
Steven Rostedta1d0ce82010-06-08 11:22:06 -0400211 return 0;
212
213#ifdef CONFIG_PERF_EVENTS
214 case TRACE_REG_PERF_REGISTER:
215 return tracepoint_probe_register(call->name,
216 call->class->perf_probe,
217 call);
218 case TRACE_REG_PERF_UNREGISTER:
219 tracepoint_probe_unregister(call->name,
220 call->class->perf_probe,
221 call);
222 return 0;
Jiri Olsaceec0b62012-02-15 15:51:49 +0100223 case TRACE_REG_PERF_OPEN:
224 case TRACE_REG_PERF_CLOSE:
Jiri Olsa489c75c2012-02-15 15:51:50 +0100225 case TRACE_REG_PERF_ADD:
226 case TRACE_REG_PERF_DEL:
Jiri Olsaceec0b62012-02-15 15:51:49 +0100227 return 0;
Steven Rostedta1d0ce82010-06-08 11:22:06 -0400228#endif
229 }
230 return 0;
231}
232EXPORT_SYMBOL_GPL(ftrace_event_reg);
233
Li Zefane870e9a2010-07-02 11:07:32 +0800234void trace_event_enable_cmd_record(bool enable)
235{
Steven Rostedtae63b312012-05-03 23:09:03 -0400236 struct ftrace_event_file *file;
237 struct trace_array *tr;
Li Zefane870e9a2010-07-02 11:07:32 +0800238
239 mutex_lock(&event_mutex);
Steven Rostedtae63b312012-05-03 23:09:03 -0400240 do_for_each_event_file(tr, file) {
241
242 if (!(file->flags & FTRACE_EVENT_FL_ENABLED))
Li Zefane870e9a2010-07-02 11:07:32 +0800243 continue;
244
245 if (enable) {
246 tracing_start_cmdline_record();
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400247 set_bit(FTRACE_EVENT_FL_RECORDED_CMD_BIT, &file->flags);
Li Zefane870e9a2010-07-02 11:07:32 +0800248 } else {
249 tracing_stop_cmdline_record();
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400250 clear_bit(FTRACE_EVENT_FL_RECORDED_CMD_BIT, &file->flags);
Li Zefane870e9a2010-07-02 11:07:32 +0800251 }
Steven Rostedtae63b312012-05-03 23:09:03 -0400252 } while_for_each_event_file();
Li Zefane870e9a2010-07-02 11:07:32 +0800253 mutex_unlock(&event_mutex);
254}
255
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400256static int __ftrace_event_enable_disable(struct ftrace_event_file *file,
257 int enable, int soft_disable)
Steven Rostedtfd994982009-02-28 02:41:25 -0500258{
Steven Rostedtae63b312012-05-03 23:09:03 -0400259 struct ftrace_event_call *call = file->event_call;
Li Zefan3b8e4272009-12-08 11:14:52 +0800260 int ret = 0;
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400261 int disable;
Li Zefan3b8e4272009-12-08 11:14:52 +0800262
Steven Rostedtfd994982009-02-28 02:41:25 -0500263 switch (enable) {
264 case 0:
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400265 /*
Masami Hiramatsu1cf4c072013-05-09 14:44:29 +0900266 * When soft_disable is set and enable is cleared, the sm_ref
267 * reference counter is decremented. If it reaches 0, we want
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400268 * to clear the SOFT_DISABLED flag but leave the event in the
269 * state that it was. That is, if the event was enabled and
270 * SOFT_DISABLED isn't set, then do nothing. But if SOFT_DISABLED
271 * is set we do not want the event to be enabled before we
272 * clear the bit.
273 *
274 * When soft_disable is not set but the SOFT_MODE flag is,
275 * we do nothing. Do not disable the tracepoint, otherwise
276 * "soft enable"s (clearing the SOFT_DISABLED bit) wont work.
277 */
278 if (soft_disable) {
Masami Hiramatsu1cf4c072013-05-09 14:44:29 +0900279 if (atomic_dec_return(&file->sm_ref) > 0)
280 break;
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400281 disable = file->flags & FTRACE_EVENT_FL_SOFT_DISABLED;
282 clear_bit(FTRACE_EVENT_FL_SOFT_MODE_BIT, &file->flags);
283 } else
284 disable = !(file->flags & FTRACE_EVENT_FL_SOFT_MODE);
285
286 if (disable && (file->flags & FTRACE_EVENT_FL_ENABLED)) {
287 clear_bit(FTRACE_EVENT_FL_ENABLED_BIT, &file->flags);
Steven Rostedtae63b312012-05-03 23:09:03 -0400288 if (file->flags & FTRACE_EVENT_FL_RECORDED_CMD) {
Li Zefane870e9a2010-07-02 11:07:32 +0800289 tracing_stop_cmdline_record();
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400290 clear_bit(FTRACE_EVENT_FL_RECORDED_CMD_BIT, &file->flags);
Li Zefane870e9a2010-07-02 11:07:32 +0800291 }
Steven Rostedtae63b312012-05-03 23:09:03 -0400292 call->class->reg(call, TRACE_REG_UNREGISTER, file);
Steven Rostedtfd994982009-02-28 02:41:25 -0500293 }
Tom Zanussi3baa5e42013-06-29 00:08:07 -0500294 /* If in SOFT_MODE, just set the SOFT_DISABLE_BIT, else clear it */
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400295 if (file->flags & FTRACE_EVENT_FL_SOFT_MODE)
296 set_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &file->flags);
Tom Zanussi3baa5e42013-06-29 00:08:07 -0500297 else
298 clear_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &file->flags);
Steven Rostedtfd994982009-02-28 02:41:25 -0500299 break;
300 case 1:
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400301 /*
302 * When soft_disable is set and enable is set, we want to
303 * register the tracepoint for the event, but leave the event
304 * as is. That means, if the event was already enabled, we do
305 * nothing (but set SOFT_MODE). If the event is disabled, we
306 * set SOFT_DISABLED before enabling the event tracepoint, so
307 * it still seems to be disabled.
308 */
309 if (!soft_disable)
310 clear_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &file->flags);
Masami Hiramatsu1cf4c072013-05-09 14:44:29 +0900311 else {
312 if (atomic_inc_return(&file->sm_ref) > 1)
313 break;
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400314 set_bit(FTRACE_EVENT_FL_SOFT_MODE_BIT, &file->flags);
Masami Hiramatsu1cf4c072013-05-09 14:44:29 +0900315 }
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400316
Steven Rostedtae63b312012-05-03 23:09:03 -0400317 if (!(file->flags & FTRACE_EVENT_FL_ENABLED)) {
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400318
319 /* Keep the event disabled, when going to SOFT_MODE. */
320 if (soft_disable)
321 set_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &file->flags);
322
Li Zefane870e9a2010-07-02 11:07:32 +0800323 if (trace_flags & TRACE_ITER_RECORD_CMD) {
324 tracing_start_cmdline_record();
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400325 set_bit(FTRACE_EVENT_FL_RECORDED_CMD_BIT, &file->flags);
Li Zefane870e9a2010-07-02 11:07:32 +0800326 }
Steven Rostedtae63b312012-05-03 23:09:03 -0400327 ret = call->class->reg(call, TRACE_REG_REGISTER, file);
Li Zefan3b8e4272009-12-08 11:14:52 +0800328 if (ret) {
329 tracing_stop_cmdline_record();
330 pr_info("event trace: Could not enable event "
331 "%s\n", call->name);
332 break;
333 }
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400334 set_bit(FTRACE_EVENT_FL_ENABLED_BIT, &file->flags);
Steven Rostedt (Red Hat)575380d2013-03-04 23:05:12 -0500335
336 /* WAS_ENABLED gets set but never cleared. */
337 call->flags |= TRACE_EVENT_FL_WAS_ENABLED;
Steven Rostedtfd994982009-02-28 02:41:25 -0500338 }
Steven Rostedtfd994982009-02-28 02:41:25 -0500339 break;
340 }
Li Zefan3b8e4272009-12-08 11:14:52 +0800341
342 return ret;
Steven Rostedtfd994982009-02-28 02:41:25 -0500343}
344
Tom Zanussi85f2b082013-10-24 08:59:24 -0500345int trace_event_enable_disable(struct ftrace_event_file *file,
346 int enable, int soft_disable)
347{
348 return __ftrace_event_enable_disable(file, enable, soft_disable);
349}
350
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400351static int ftrace_event_enable_disable(struct ftrace_event_file *file,
352 int enable)
353{
354 return __ftrace_event_enable_disable(file, enable, 0);
355}
356
Steven Rostedtae63b312012-05-03 23:09:03 -0400357static void ftrace_clear_events(struct trace_array *tr)
Zhaolei0e907c92009-05-25 18:13:59 +0800358{
Steven Rostedtae63b312012-05-03 23:09:03 -0400359 struct ftrace_event_file *file;
Zhaolei0e907c92009-05-25 18:13:59 +0800360
361 mutex_lock(&event_mutex);
Steven Rostedtae63b312012-05-03 23:09:03 -0400362 list_for_each_entry(file, &tr->events, list) {
363 ftrace_event_enable_disable(file, 0);
Zhaolei0e907c92009-05-25 18:13:59 +0800364 }
365 mutex_unlock(&event_mutex);
366}
367
Steven Rostedte9dbfae2011-07-05 11:36:06 -0400368static void __put_system(struct event_subsystem *system)
369{
370 struct event_filter *filter = system->filter;
371
Steven Rostedt6e94a782013-06-27 10:58:31 -0400372 WARN_ON_ONCE(system_refcount(system) == 0);
373 if (system_refcount_dec(system))
Steven Rostedte9dbfae2011-07-05 11:36:06 -0400374 return;
375
Steven Rostedtae63b312012-05-03 23:09:03 -0400376 list_del(&system->list);
377
Steven Rostedte9dbfae2011-07-05 11:36:06 -0400378 if (filter) {
379 kfree(filter->filter_string);
380 kfree(filter);
381 }
Steven Rostedt6e94a782013-06-27 10:58:31 -0400382 if (system->ref_count & SYSTEM_FL_FREE_NAME)
383 kfree(system->name);
Steven Rostedte9dbfae2011-07-05 11:36:06 -0400384 kfree(system);
385}
386
387static void __get_system(struct event_subsystem *system)
388{
Steven Rostedt6e94a782013-06-27 10:58:31 -0400389 WARN_ON_ONCE(system_refcount(system) == 0);
390 system_refcount_inc(system);
Steven Rostedte9dbfae2011-07-05 11:36:06 -0400391}
392
Steven Rostedtae63b312012-05-03 23:09:03 -0400393static void __get_system_dir(struct ftrace_subsystem_dir *dir)
394{
395 WARN_ON_ONCE(dir->ref_count == 0);
396 dir->ref_count++;
397 __get_system(dir->subsystem);
398}
399
400static void __put_system_dir(struct ftrace_subsystem_dir *dir)
401{
402 WARN_ON_ONCE(dir->ref_count == 0);
403 /* If the subsystem is about to be freed, the dir must be too */
Steven Rostedt6e94a782013-06-27 10:58:31 -0400404 WARN_ON_ONCE(system_refcount(dir->subsystem) == 1 && dir->ref_count != 1);
Steven Rostedtae63b312012-05-03 23:09:03 -0400405
406 __put_system(dir->subsystem);
407 if (!--dir->ref_count)
408 kfree(dir);
409}
410
411static void put_system(struct ftrace_subsystem_dir *dir)
Steven Rostedte9dbfae2011-07-05 11:36:06 -0400412{
413 mutex_lock(&event_mutex);
Steven Rostedtae63b312012-05-03 23:09:03 -0400414 __put_system_dir(dir);
Steven Rostedte9dbfae2011-07-05 11:36:06 -0400415 mutex_unlock(&event_mutex);
416}
417
Oleg Nesterovf6a84bd2013-07-26 19:25:47 +0200418static void remove_subsystem(struct ftrace_subsystem_dir *dir)
419{
420 if (!dir)
421 return;
422
423 if (!--dir->nr_events) {
424 debugfs_remove_recursive(dir->entry);
425 list_del(&dir->list);
426 __put_system_dir(dir);
427 }
428}
429
Oleg Nesterovf6a84bd2013-07-26 19:25:47 +0200430static void remove_event_file_dir(struct ftrace_event_file *file)
431{
Oleg Nesterovbf682c32013-07-28 20:35:27 +0200432 struct dentry *dir = file->dir;
433 struct dentry *child;
434
435 if (dir) {
436 spin_lock(&dir->d_lock); /* probably unneeded */
437 list_for_each_entry(child, &dir->d_subdirs, d_u.d_child) {
438 if (child->d_inode) /* probably unneeded */
439 child->d_inode->i_private = NULL;
440 }
441 spin_unlock(&dir->d_lock);
442
443 debugfs_remove_recursive(dir);
444 }
445
Oleg Nesterovf6a84bd2013-07-26 19:25:47 +0200446 list_del(&file->list);
Oleg Nesterovf6a84bd2013-07-26 19:25:47 +0200447 remove_subsystem(file->system);
448 kmem_cache_free(file_cachep, file);
449}
450
Li Zefan8f31bfe2009-05-08 10:31:42 +0800451/*
452 * __ftrace_set_clr_event(NULL, NULL, NULL, set) will set/unset all events.
453 */
Steven Rostedt (Red Hat)2a6c24a2013-07-02 14:48:23 -0400454static int
455__ftrace_set_clr_event_nolock(struct trace_array *tr, const char *match,
456 const char *sub, const char *event, int set)
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500457{
Steven Rostedtae63b312012-05-03 23:09:03 -0400458 struct ftrace_event_file *file;
Steven Rostedta59fd602009-04-10 13:52:20 -0400459 struct ftrace_event_call *call;
Steven Rostedt29f93942009-05-08 16:06:47 -0400460 int ret = -EINVAL;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500461
Steven Rostedtae63b312012-05-03 23:09:03 -0400462 list_for_each_entry(file, &tr->events, list) {
463
464 call = file->event_call;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500465
Steven Rostedta1d0ce82010-06-08 11:22:06 -0400466 if (!call->name || !call->class || !call->class->reg)
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500467 continue;
Steven Rostedt1473e442009-02-24 14:15:08 -0500468
Steven Rostedt9b637762012-05-10 15:55:43 -0400469 if (call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)
470 continue;
471
Steven Rostedtb628b3e2009-02-27 23:32:58 -0500472 if (match &&
473 strcmp(match, call->name) != 0 &&
Steven Rostedt8f082012010-04-20 10:47:33 -0400474 strcmp(match, call->class->system) != 0)
Steven Rostedtb628b3e2009-02-27 23:32:58 -0500475 continue;
476
Steven Rostedt8f082012010-04-20 10:47:33 -0400477 if (sub && strcmp(sub, call->class->system) != 0)
Steven Rostedtb628b3e2009-02-27 23:32:58 -0500478 continue;
479
480 if (event && strcmp(event, call->name) != 0)
Steven Rostedt1473e442009-02-24 14:15:08 -0500481 continue;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500482
Steven Rostedtae63b312012-05-03 23:09:03 -0400483 ftrace_event_enable_disable(file, set);
Steven Rostedtfd994982009-02-28 02:41:25 -0500484
Steven Rostedtb628b3e2009-02-27 23:32:58 -0500485 ret = 0;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500486 }
Steven Rostedt (Red Hat)2a6c24a2013-07-02 14:48:23 -0400487
488 return ret;
489}
490
491static int __ftrace_set_clr_event(struct trace_array *tr, const char *match,
492 const char *sub, const char *event, int set)
493{
494 int ret;
495
496 mutex_lock(&event_mutex);
497 ret = __ftrace_set_clr_event_nolock(tr, match, sub, event, set);
Steven Rostedt11a241a2009-03-02 11:49:04 -0500498 mutex_unlock(&event_mutex);
499
Steven Rostedtb628b3e2009-02-27 23:32:58 -0500500 return ret;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500501}
502
Steven Rostedtae63b312012-05-03 23:09:03 -0400503static int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set)
Li Zefan8f31bfe2009-05-08 10:31:42 +0800504{
505 char *event = NULL, *sub = NULL, *match;
506
507 /*
508 * The buf format can be <subsystem>:<event-name>
509 * *:<event-name> means any event by that name.
510 * :<event-name> is the same.
511 *
512 * <subsystem>:* means all events in that subsystem
513 * <subsystem>: means the same.
514 *
515 * <name> (no ':') means all events in a subsystem with
516 * the name <name> or any event that matches <name>
517 */
518
519 match = strsep(&buf, ":");
520 if (buf) {
521 sub = match;
522 event = buf;
523 match = NULL;
524
525 if (!strlen(sub) || strcmp(sub, "*") == 0)
526 sub = NULL;
527 if (!strlen(event) || strcmp(event, "*") == 0)
528 event = NULL;
529 }
530
Steven Rostedtae63b312012-05-03 23:09:03 -0400531 return __ftrace_set_clr_event(tr, match, sub, event, set);
Li Zefan8f31bfe2009-05-08 10:31:42 +0800532}
533
Steven Rostedt4671c792009-05-08 16:27:41 -0400534/**
535 * trace_set_clr_event - enable or disable an event
536 * @system: system name to match (NULL for any system)
537 * @event: event name to match (NULL for all events, within system)
538 * @set: 1 to enable, 0 to disable
539 *
540 * This is a way for other parts of the kernel to enable or disable
541 * event recording.
542 *
543 * Returns 0 on success, -EINVAL if the parameters do not match any
544 * registered events.
545 */
546int trace_set_clr_event(const char *system, const char *event, int set)
547{
Steven Rostedtae63b312012-05-03 23:09:03 -0400548 struct trace_array *tr = top_trace_array();
549
550 return __ftrace_set_clr_event(tr, NULL, system, event, set);
Steven Rostedt4671c792009-05-08 16:27:41 -0400551}
Yuanhan Liu56355b82010-11-08 14:05:12 +0800552EXPORT_SYMBOL_GPL(trace_set_clr_event);
Steven Rostedt4671c792009-05-08 16:27:41 -0400553
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500554/* 128 should be much more than enough */
555#define EVENT_BUF_SIZE 127
556
557static ssize_t
558ftrace_event_write(struct file *file, const char __user *ubuf,
559 size_t cnt, loff_t *ppos)
560{
jolsa@redhat.com48966362009-09-11 17:29:28 +0200561 struct trace_parser parser;
Steven Rostedtae63b312012-05-03 23:09:03 -0400562 struct seq_file *m = file->private_data;
563 struct trace_array *tr = m->private;
Li Zefan4ba79782009-09-22 13:52:20 +0800564 ssize_t read, ret;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500565
Li Zefan4ba79782009-09-22 13:52:20 +0800566 if (!cnt)
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500567 return 0;
568
Steven Rostedt1852fcc2009-03-11 14:33:00 -0400569 ret = tracing_update_buffers();
570 if (ret < 0)
571 return ret;
572
jolsa@redhat.com48966362009-09-11 17:29:28 +0200573 if (trace_parser_get_init(&parser, EVENT_BUF_SIZE + 1))
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500574 return -ENOMEM;
575
jolsa@redhat.com48966362009-09-11 17:29:28 +0200576 read = trace_get_user(&parser, ubuf, cnt, ppos);
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500577
Li Zefan4ba79782009-09-22 13:52:20 +0800578 if (read >= 0 && trace_parser_loaded((&parser))) {
jolsa@redhat.com48966362009-09-11 17:29:28 +0200579 int set = 1;
580
581 if (*parser.buffer == '!')
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500582 set = 0;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500583
jolsa@redhat.com48966362009-09-11 17:29:28 +0200584 parser.buffer[parser.idx] = 0;
585
Steven Rostedtae63b312012-05-03 23:09:03 -0400586 ret = ftrace_set_clr_event(tr, parser.buffer + !set, set);
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500587 if (ret)
jolsa@redhat.com48966362009-09-11 17:29:28 +0200588 goto out_put;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500589 }
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500590
591 ret = read;
592
jolsa@redhat.com48966362009-09-11 17:29:28 +0200593 out_put:
594 trace_parser_put(&parser);
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500595
596 return ret;
597}
598
599static void *
600t_next(struct seq_file *m, void *v, loff_t *pos)
601{
Steven Rostedtae63b312012-05-03 23:09:03 -0400602 struct ftrace_event_file *file = v;
603 struct ftrace_event_call *call;
604 struct trace_array *tr = m->private;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500605
606 (*pos)++;
607
Steven Rostedtae63b312012-05-03 23:09:03 -0400608 list_for_each_entry_continue(file, &tr->events, list) {
609 call = file->event_call;
Steven Rostedt40e26812009-03-10 11:32:40 -0400610 /*
611 * The ftrace subsystem is for showing formats only.
612 * They can not be enabled or disabled via the event files.
613 */
Steven Rostedta1d0ce82010-06-08 11:22:06 -0400614 if (call->class && call->class->reg)
Steven Rostedtae63b312012-05-03 23:09:03 -0400615 return file;
Steven Rostedt40e26812009-03-10 11:32:40 -0400616 }
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500617
Li Zefan30bd39c2009-09-18 14:07:05 +0800618 return NULL;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500619}
620
621static void *t_start(struct seq_file *m, loff_t *pos)
622{
Steven Rostedtae63b312012-05-03 23:09:03 -0400623 struct ftrace_event_file *file;
624 struct trace_array *tr = m->private;
Li Zefane1c7e2a2009-06-24 09:52:29 +0800625 loff_t l;
626
Li Zefan20c89282009-05-06 10:33:45 +0800627 mutex_lock(&event_mutex);
Li Zefane1c7e2a2009-06-24 09:52:29 +0800628
Steven Rostedtae63b312012-05-03 23:09:03 -0400629 file = list_entry(&tr->events, struct ftrace_event_file, list);
Li Zefane1c7e2a2009-06-24 09:52:29 +0800630 for (l = 0; l <= *pos; ) {
Steven Rostedtae63b312012-05-03 23:09:03 -0400631 file = t_next(m, file, &l);
632 if (!file)
Li Zefane1c7e2a2009-06-24 09:52:29 +0800633 break;
634 }
Steven Rostedtae63b312012-05-03 23:09:03 -0400635 return file;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500636}
637
638static void *
639s_next(struct seq_file *m, void *v, loff_t *pos)
640{
Steven Rostedtae63b312012-05-03 23:09:03 -0400641 struct ftrace_event_file *file = v;
642 struct trace_array *tr = m->private;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500643
644 (*pos)++;
645
Steven Rostedtae63b312012-05-03 23:09:03 -0400646 list_for_each_entry_continue(file, &tr->events, list) {
647 if (file->flags & FTRACE_EVENT_FL_ENABLED)
648 return file;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500649 }
650
Li Zefan30bd39c2009-09-18 14:07:05 +0800651 return NULL;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500652}
653
654static void *s_start(struct seq_file *m, loff_t *pos)
655{
Steven Rostedtae63b312012-05-03 23:09:03 -0400656 struct ftrace_event_file *file;
657 struct trace_array *tr = m->private;
Li Zefane1c7e2a2009-06-24 09:52:29 +0800658 loff_t l;
659
Li Zefan20c89282009-05-06 10:33:45 +0800660 mutex_lock(&event_mutex);
Li Zefane1c7e2a2009-06-24 09:52:29 +0800661
Steven Rostedtae63b312012-05-03 23:09:03 -0400662 file = list_entry(&tr->events, struct ftrace_event_file, list);
Li Zefane1c7e2a2009-06-24 09:52:29 +0800663 for (l = 0; l <= *pos; ) {
Steven Rostedtae63b312012-05-03 23:09:03 -0400664 file = s_next(m, file, &l);
665 if (!file)
Li Zefane1c7e2a2009-06-24 09:52:29 +0800666 break;
667 }
Steven Rostedtae63b312012-05-03 23:09:03 -0400668 return file;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500669}
670
671static int t_show(struct seq_file *m, void *v)
672{
Steven Rostedtae63b312012-05-03 23:09:03 -0400673 struct ftrace_event_file *file = v;
674 struct ftrace_event_call *call = file->event_call;
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500675
Steven Rostedt8f082012010-04-20 10:47:33 -0400676 if (strcmp(call->class->system, TRACE_SYSTEM) != 0)
677 seq_printf(m, "%s:", call->class->system);
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500678 seq_printf(m, "%s\n", call->name);
679
680 return 0;
681}
682
683static void t_stop(struct seq_file *m, void *p)
684{
Li Zefan20c89282009-05-06 10:33:45 +0800685 mutex_unlock(&event_mutex);
Steven Rostedtb77e38a2009-02-24 10:21:36 -0500686}
687
Steven Rostedt1473e442009-02-24 14:15:08 -0500688static ssize_t
689event_enable_read(struct file *filp, char __user *ubuf, size_t cnt,
690 loff_t *ppos)
691{
Oleg Nesterovbc6f6b02013-07-26 19:25:36 +0200692 struct ftrace_event_file *file;
693 unsigned long flags;
Tom Zanussia4390592013-06-29 00:08:04 -0500694 char buf[4] = "0";
Steven Rostedt1473e442009-02-24 14:15:08 -0500695
Oleg Nesterovbc6f6b02013-07-26 19:25:36 +0200696 mutex_lock(&event_mutex);
697 file = event_file_data(filp);
698 if (likely(file))
699 flags = file->flags;
700 mutex_unlock(&event_mutex);
701
702 if (!file)
703 return -ENODEV;
704
705 if (flags & FTRACE_EVENT_FL_ENABLED &&
706 !(flags & FTRACE_EVENT_FL_SOFT_DISABLED))
Tom Zanussia4390592013-06-29 00:08:04 -0500707 strcpy(buf, "1");
708
Oleg Nesterovbc6f6b02013-07-26 19:25:36 +0200709 if (flags & FTRACE_EVENT_FL_SOFT_DISABLED ||
710 flags & FTRACE_EVENT_FL_SOFT_MODE)
Tom Zanussia4390592013-06-29 00:08:04 -0500711 strcat(buf, "*");
712
713 strcat(buf, "\n");
Steven Rostedt1473e442009-02-24 14:15:08 -0500714
Steven Rostedt (Red Hat)417944c2013-03-12 13:26:18 -0400715 return simple_read_from_buffer(ubuf, cnt, ppos, buf, strlen(buf));
Steven Rostedt1473e442009-02-24 14:15:08 -0500716}
717
718static ssize_t
719event_enable_write(struct file *filp, const char __user *ubuf, size_t cnt,
720 loff_t *ppos)
721{
Oleg Nesterovbc6f6b02013-07-26 19:25:36 +0200722 struct ftrace_event_file *file;
Steven Rostedt1473e442009-02-24 14:15:08 -0500723 unsigned long val;
724 int ret;
725
Peter Huewe22fe9b52011-06-07 21:58:27 +0200726 ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
727 if (ret)
Steven Rostedt1473e442009-02-24 14:15:08 -0500728 return ret;
729
Steven Rostedt1852fcc2009-03-11 14:33:00 -0400730 ret = tracing_update_buffers();
731 if (ret < 0)
732 return ret;
733
Steven Rostedt1473e442009-02-24 14:15:08 -0500734 switch (val) {
735 case 0:
Steven Rostedt1473e442009-02-24 14:15:08 -0500736 case 1:
Oleg Nesterovbc6f6b02013-07-26 19:25:36 +0200737 ret = -ENODEV;
Steven Rostedt11a241a2009-03-02 11:49:04 -0500738 mutex_lock(&event_mutex);
Oleg Nesterovbc6f6b02013-07-26 19:25:36 +0200739 file = event_file_data(filp);
740 if (likely(file))
741 ret = ftrace_event_enable_disable(file, val);
Steven Rostedt11a241a2009-03-02 11:49:04 -0500742 mutex_unlock(&event_mutex);
Steven Rostedt1473e442009-02-24 14:15:08 -0500743 break;
744
745 default:
746 return -EINVAL;
747 }
748
749 *ppos += cnt;
750
Li Zefan3b8e4272009-12-08 11:14:52 +0800751 return ret ? ret : cnt;
Steven Rostedt1473e442009-02-24 14:15:08 -0500752}
753
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400754static ssize_t
755system_enable_read(struct file *filp, char __user *ubuf, size_t cnt,
756 loff_t *ppos)
757{
Li Zefanc142b152009-05-08 10:32:05 +0800758 const char set_to_char[4] = { '?', '0', '1', 'X' };
Steven Rostedtae63b312012-05-03 23:09:03 -0400759 struct ftrace_subsystem_dir *dir = filp->private_data;
760 struct event_subsystem *system = dir->subsystem;
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400761 struct ftrace_event_call *call;
Steven Rostedtae63b312012-05-03 23:09:03 -0400762 struct ftrace_event_file *file;
763 struct trace_array *tr = dir->tr;
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400764 char buf[2];
Li Zefanc142b152009-05-08 10:32:05 +0800765 int set = 0;
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400766 int ret;
767
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400768 mutex_lock(&event_mutex);
Steven Rostedtae63b312012-05-03 23:09:03 -0400769 list_for_each_entry(file, &tr->events, list) {
770 call = file->event_call;
Steven Rostedta1d0ce82010-06-08 11:22:06 -0400771 if (!call->name || !call->class || !call->class->reg)
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400772 continue;
773
Steven Rostedt40ee4df2011-07-05 14:32:51 -0400774 if (system && strcmp(call->class->system, system->name) != 0)
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400775 continue;
776
777 /*
778 * We need to find out if all the events are set
779 * or if all events or cleared, or if we have
780 * a mixture.
781 */
Steven Rostedtae63b312012-05-03 23:09:03 -0400782 set |= (1 << !!(file->flags & FTRACE_EVENT_FL_ENABLED));
Li Zefanc142b152009-05-08 10:32:05 +0800783
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400784 /*
785 * If we have a mixture, no need to look further.
786 */
Li Zefanc142b152009-05-08 10:32:05 +0800787 if (set == 3)
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400788 break;
789 }
790 mutex_unlock(&event_mutex);
791
Li Zefanc142b152009-05-08 10:32:05 +0800792 buf[0] = set_to_char[set];
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400793 buf[1] = '\n';
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400794
795 ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, 2);
796
797 return ret;
798}
799
800static ssize_t
801system_enable_write(struct file *filp, const char __user *ubuf, size_t cnt,
802 loff_t *ppos)
803{
Steven Rostedtae63b312012-05-03 23:09:03 -0400804 struct ftrace_subsystem_dir *dir = filp->private_data;
805 struct event_subsystem *system = dir->subsystem;
Steven Rostedt40ee4df2011-07-05 14:32:51 -0400806 const char *name = NULL;
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400807 unsigned long val;
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400808 ssize_t ret;
809
Peter Huewe22fe9b52011-06-07 21:58:27 +0200810 ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
811 if (ret)
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400812 return ret;
813
814 ret = tracing_update_buffers();
815 if (ret < 0)
816 return ret;
817
Li Zefan8f31bfe2009-05-08 10:31:42 +0800818 if (val != 0 && val != 1)
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400819 return -EINVAL;
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400820
Steven Rostedt40ee4df2011-07-05 14:32:51 -0400821 /*
822 * Opening of "enable" adds a ref count to system,
823 * so the name is safe to use.
824 */
825 if (system)
826 name = system->name;
827
Steven Rostedtae63b312012-05-03 23:09:03 -0400828 ret = __ftrace_set_clr_event(dir->tr, NULL, name, NULL, val);
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400829 if (ret)
Li Zefan8f31bfe2009-05-08 10:31:42 +0800830 goto out;
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400831
832 ret = cnt;
833
Li Zefan8f31bfe2009-05-08 10:31:42 +0800834out:
Steven Rostedt8ae79a12009-05-06 22:52:15 -0400835 *ppos += cnt;
836
837 return ret;
838}
839
Steven Rostedt2a37a3d2010-06-03 15:21:34 -0400840enum {
841 FORMAT_HEADER = 1,
Li Zefan86397dc2010-08-17 13:53:06 +0800842 FORMAT_FIELD_SEPERATOR = 2,
843 FORMAT_PRINTFMT = 3,
Steven Rostedt2a37a3d2010-06-03 15:21:34 -0400844};
845
846static void *f_next(struct seq_file *m, void *v, loff_t *pos)
Steven Rostedt981d0812009-03-02 13:53:59 -0500847{
Oleg Nesterovc5a44a12013-07-26 19:25:43 +0200848 struct ftrace_event_call *call = event_file_data(m->private);
Li Zefan86397dc2010-08-17 13:53:06 +0800849 struct list_head *common_head = &ftrace_common_fields;
850 struct list_head *head = trace_get_fields(call);
Oleg Nesterov7710b632013-07-18 20:47:10 +0200851 struct list_head *node = v;
Steven Rostedt981d0812009-03-02 13:53:59 -0500852
Steven Rostedt2a37a3d2010-06-03 15:21:34 -0400853 (*pos)++;
Lai Jiangshan5a65e952009-12-15 15:39:53 +0800854
Steven Rostedt2a37a3d2010-06-03 15:21:34 -0400855 switch ((unsigned long)v) {
856 case FORMAT_HEADER:
Oleg Nesterov7710b632013-07-18 20:47:10 +0200857 node = common_head;
858 break;
Li Zefan86397dc2010-08-17 13:53:06 +0800859
860 case FORMAT_FIELD_SEPERATOR:
Oleg Nesterov7710b632013-07-18 20:47:10 +0200861 node = head;
862 break;
Lai Jiangshan5a65e952009-12-15 15:39:53 +0800863
Steven Rostedt2a37a3d2010-06-03 15:21:34 -0400864 case FORMAT_PRINTFMT:
865 /* all done */
866 return NULL;
Lai Jiangshan5a65e952009-12-15 15:39:53 +0800867 }
868
Oleg Nesterov7710b632013-07-18 20:47:10 +0200869 node = node->prev;
870 if (node == common_head)
Li Zefan86397dc2010-08-17 13:53:06 +0800871 return (void *)FORMAT_FIELD_SEPERATOR;
Oleg Nesterov7710b632013-07-18 20:47:10 +0200872 else if (node == head)
Steven Rostedt2a37a3d2010-06-03 15:21:34 -0400873 return (void *)FORMAT_PRINTFMT;
Oleg Nesterov7710b632013-07-18 20:47:10 +0200874 else
875 return node;
Steven Rostedt2a37a3d2010-06-03 15:21:34 -0400876}
877
878static int f_show(struct seq_file *m, void *v)
879{
Oleg Nesterovc5a44a12013-07-26 19:25:43 +0200880 struct ftrace_event_call *call = event_file_data(m->private);
Steven Rostedt2a37a3d2010-06-03 15:21:34 -0400881 struct ftrace_event_field *field;
882 const char *array_descriptor;
883
884 switch ((unsigned long)v) {
885 case FORMAT_HEADER:
886 seq_printf(m, "name: %s\n", call->name);
887 seq_printf(m, "ID: %d\n", call->event.type);
888 seq_printf(m, "format:\n");
Li Zefan8728fe52010-05-24 16:22:49 +0800889 return 0;
890
Li Zefan86397dc2010-08-17 13:53:06 +0800891 case FORMAT_FIELD_SEPERATOR:
892 seq_putc(m, '\n');
893 return 0;
894
Steven Rostedt2a37a3d2010-06-03 15:21:34 -0400895 case FORMAT_PRINTFMT:
896 seq_printf(m, "\nprint fmt: %s\n",
897 call->print_fmt);
898 return 0;
Steven Rostedt981d0812009-03-02 13:53:59 -0500899 }
900
Oleg Nesterov7710b632013-07-18 20:47:10 +0200901 field = list_entry(v, struct ftrace_event_field, link);
Steven Rostedt2a37a3d2010-06-03 15:21:34 -0400902 /*
903 * Smartly shows the array type(except dynamic array).
904 * Normal:
905 * field:TYPE VAR
906 * If TYPE := TYPE[LEN], it is shown:
907 * field:TYPE VAR[LEN]
908 */
909 array_descriptor = strchr(field->type, '[');
910
911 if (!strncmp(field->type, "__data_loc", 10))
912 array_descriptor = NULL;
913
914 if (!array_descriptor)
915 seq_printf(m, "\tfield:%s %s;\toffset:%u;\tsize:%u;\tsigned:%d;\n",
916 field->type, field->name, field->offset,
917 field->size, !!field->is_signed);
918 else
919 seq_printf(m, "\tfield:%.*s %s%s;\toffset:%u;\tsize:%u;\tsigned:%d;\n",
920 (int)(array_descriptor - field->type),
921 field->type, field->name,
922 array_descriptor, field->offset,
923 field->size, !!field->is_signed);
924
925 return 0;
926}
927
Oleg Nesterov7710b632013-07-18 20:47:10 +0200928static void *f_start(struct seq_file *m, loff_t *pos)
929{
930 void *p = (void *)FORMAT_HEADER;
931 loff_t l = 0;
932
Oleg Nesterovc5a44a12013-07-26 19:25:43 +0200933 /* ->stop() is called even if ->start() fails */
934 mutex_lock(&event_mutex);
935 if (!event_file_data(m->private))
936 return ERR_PTR(-ENODEV);
937
Oleg Nesterov7710b632013-07-18 20:47:10 +0200938 while (l < *pos && p)
939 p = f_next(m, p, &l);
940
941 return p;
942}
943
Steven Rostedt2a37a3d2010-06-03 15:21:34 -0400944static void f_stop(struct seq_file *m, void *p)
945{
Oleg Nesterovc5a44a12013-07-26 19:25:43 +0200946 mutex_unlock(&event_mutex);
Steven Rostedt2a37a3d2010-06-03 15:21:34 -0400947}
948
949static const struct seq_operations trace_format_seq_ops = {
950 .start = f_start,
951 .next = f_next,
952 .stop = f_stop,
953 .show = f_show,
954};
955
956static int trace_format_open(struct inode *inode, struct file *file)
957{
Steven Rostedt2a37a3d2010-06-03 15:21:34 -0400958 struct seq_file *m;
959 int ret;
960
961 ret = seq_open(file, &trace_format_seq_ops);
962 if (ret < 0)
963 return ret;
964
965 m = file->private_data;
Oleg Nesterovc5a44a12013-07-26 19:25:43 +0200966 m->private = file;
Steven Rostedt2a37a3d2010-06-03 15:21:34 -0400967
968 return 0;
Steven Rostedt981d0812009-03-02 13:53:59 -0500969}
970
Peter Zijlstra23725ae2009-03-19 20:26:13 +0100971static ssize_t
972event_id_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos)
973{
Oleg Nesterov1a111262013-07-26 19:25:32 +0200974 int id = (long)event_file_data(filp);
Oleg Nesterovcd458ba2013-07-18 20:47:12 +0200975 char buf[32];
976 int len;
Peter Zijlstra23725ae2009-03-19 20:26:13 +0100977
978 if (*ppos)
979 return 0;
980
Oleg Nesterov1a111262013-07-26 19:25:32 +0200981 if (unlikely(!id))
982 return -ENODEV;
983
984 len = sprintf(buf, "%d\n", id);
985
Oleg Nesterovcd458ba2013-07-18 20:47:12 +0200986 return simple_read_from_buffer(ubuf, cnt, ppos, buf, len);
Peter Zijlstra23725ae2009-03-19 20:26:13 +0100987}
988
Tom Zanussi7ce7e422009-03-22 03:31:04 -0500989static ssize_t
990event_filter_read(struct file *filp, char __user *ubuf, size_t cnt,
991 loff_t *ppos)
992{
Tom Zanussif306cc82013-10-24 08:34:17 -0500993 struct ftrace_event_file *file;
Tom Zanussi7ce7e422009-03-22 03:31:04 -0500994 struct trace_seq *s;
Oleg Nesterove2912b02013-07-26 19:25:40 +0200995 int r = -ENODEV;
Tom Zanussi7ce7e422009-03-22 03:31:04 -0500996
997 if (*ppos)
998 return 0;
999
1000 s = kmalloc(sizeof(*s), GFP_KERNEL);
Oleg Nesterove2912b02013-07-26 19:25:40 +02001001
Tom Zanussi7ce7e422009-03-22 03:31:04 -05001002 if (!s)
1003 return -ENOMEM;
1004
1005 trace_seq_init(s);
1006
Oleg Nesterove2912b02013-07-26 19:25:40 +02001007 mutex_lock(&event_mutex);
Tom Zanussif306cc82013-10-24 08:34:17 -05001008 file = event_file_data(filp);
1009 if (file)
1010 print_event_filter(file, s);
Oleg Nesterove2912b02013-07-26 19:25:40 +02001011 mutex_unlock(&event_mutex);
1012
Tom Zanussif306cc82013-10-24 08:34:17 -05001013 if (file)
Oleg Nesterove2912b02013-07-26 19:25:40 +02001014 r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, s->len);
Tom Zanussi7ce7e422009-03-22 03:31:04 -05001015
1016 kfree(s);
1017
1018 return r;
1019}
1020
1021static ssize_t
1022event_filter_write(struct file *filp, const char __user *ubuf, size_t cnt,
1023 loff_t *ppos)
1024{
Tom Zanussif306cc82013-10-24 08:34:17 -05001025 struct ftrace_event_file *file;
Tom Zanussi8b372562009-04-28 03:04:59 -05001026 char *buf;
Oleg Nesterove2912b02013-07-26 19:25:40 +02001027 int err = -ENODEV;
Tom Zanussi7ce7e422009-03-22 03:31:04 -05001028
Tom Zanussi8b372562009-04-28 03:04:59 -05001029 if (cnt >= PAGE_SIZE)
Tom Zanussi7ce7e422009-03-22 03:31:04 -05001030 return -EINVAL;
1031
Tom Zanussi8b372562009-04-28 03:04:59 -05001032 buf = (char *)__get_free_page(GFP_TEMPORARY);
1033 if (!buf)
Tom Zanussi7ce7e422009-03-22 03:31:04 -05001034 return -ENOMEM;
1035
Tom Zanussi8b372562009-04-28 03:04:59 -05001036 if (copy_from_user(buf, ubuf, cnt)) {
1037 free_page((unsigned long) buf);
1038 return -EFAULT;
1039 }
1040 buf[cnt] = '\0';
1041
Oleg Nesterove2912b02013-07-26 19:25:40 +02001042 mutex_lock(&event_mutex);
Tom Zanussif306cc82013-10-24 08:34:17 -05001043 file = event_file_data(filp);
1044 if (file)
1045 err = apply_event_filter(file, buf);
Oleg Nesterove2912b02013-07-26 19:25:40 +02001046 mutex_unlock(&event_mutex);
1047
Tom Zanussi8b372562009-04-28 03:04:59 -05001048 free_page((unsigned long) buf);
1049 if (err < 0)
Tom Zanussi7ce7e422009-03-22 03:31:04 -05001050 return err;
Tom Zanussi0a19e532009-04-13 03:17:50 -05001051
Tom Zanussi7ce7e422009-03-22 03:31:04 -05001052 *ppos += cnt;
1053
1054 return cnt;
1055}
1056
Steven Rostedte9dbfae2011-07-05 11:36:06 -04001057static LIST_HEAD(event_subsystems);
1058
1059static int subsystem_open(struct inode *inode, struct file *filp)
1060{
1061 struct event_subsystem *system = NULL;
Steven Rostedtae63b312012-05-03 23:09:03 -04001062 struct ftrace_subsystem_dir *dir = NULL; /* Initialize for gcc */
1063 struct trace_array *tr;
Steven Rostedte9dbfae2011-07-05 11:36:06 -04001064 int ret;
1065
Geyslan G. Bemd6d35232013-11-06 16:02:51 -03001066 if (tracing_is_disabled())
1067 return -ENODEV;
1068
Steven Rostedte9dbfae2011-07-05 11:36:06 -04001069 /* Make sure the system still exists */
Alexander Z Lama8227412013-07-01 19:37:54 -07001070 mutex_lock(&trace_types_lock);
Steven Rostedte9dbfae2011-07-05 11:36:06 -04001071 mutex_lock(&event_mutex);
Steven Rostedtae63b312012-05-03 23:09:03 -04001072 list_for_each_entry(tr, &ftrace_trace_arrays, list) {
1073 list_for_each_entry(dir, &tr->systems, list) {
1074 if (dir == inode->i_private) {
1075 /* Don't open systems with no events */
1076 if (dir->nr_events) {
1077 __get_system_dir(dir);
1078 system = dir->subsystem;
1079 }
1080 goto exit_loop;
Steven Rostedte9dbfae2011-07-05 11:36:06 -04001081 }
Steven Rostedte9dbfae2011-07-05 11:36:06 -04001082 }
1083 }
Steven Rostedtae63b312012-05-03 23:09:03 -04001084 exit_loop:
Steven Rostedte9dbfae2011-07-05 11:36:06 -04001085 mutex_unlock(&event_mutex);
Alexander Z Lama8227412013-07-01 19:37:54 -07001086 mutex_unlock(&trace_types_lock);
Steven Rostedte9dbfae2011-07-05 11:36:06 -04001087
Steven Rostedtae63b312012-05-03 23:09:03 -04001088 if (!system)
Steven Rostedte9dbfae2011-07-05 11:36:06 -04001089 return -ENODEV;
1090
Steven Rostedtae63b312012-05-03 23:09:03 -04001091 /* Some versions of gcc think dir can be uninitialized here */
1092 WARN_ON(!dir);
1093
Steven Rostedt (Red Hat)8e2e2fa2013-07-02 15:30:53 -04001094 /* Still need to increment the ref count of the system */
1095 if (trace_array_get(tr) < 0) {
Steven Rostedtae63b312012-05-03 23:09:03 -04001096 put_system(dir);
Steven Rostedt (Red Hat)8e2e2fa2013-07-02 15:30:53 -04001097 return -ENODEV;
1098 }
1099
1100 ret = tracing_open_generic(inode, filp);
1101 if (ret < 0) {
1102 trace_array_put(tr);
1103 put_system(dir);
1104 }
Steven Rostedtae63b312012-05-03 23:09:03 -04001105
1106 return ret;
1107}
1108
1109static int system_tr_open(struct inode *inode, struct file *filp)
1110{
1111 struct ftrace_subsystem_dir *dir;
1112 struct trace_array *tr = inode->i_private;
1113 int ret;
1114
Geyslan G. Bemd6d35232013-11-06 16:02:51 -03001115 if (tracing_is_disabled())
1116 return -ENODEV;
1117
Steven Rostedt (Red Hat)8e2e2fa2013-07-02 15:30:53 -04001118 if (trace_array_get(tr) < 0)
1119 return -ENODEV;
1120
Steven Rostedtae63b312012-05-03 23:09:03 -04001121 /* Make a temporary dir that has no system but points to tr */
1122 dir = kzalloc(sizeof(*dir), GFP_KERNEL);
Steven Rostedt (Red Hat)8e2e2fa2013-07-02 15:30:53 -04001123 if (!dir) {
1124 trace_array_put(tr);
Steven Rostedtae63b312012-05-03 23:09:03 -04001125 return -ENOMEM;
Steven Rostedt (Red Hat)8e2e2fa2013-07-02 15:30:53 -04001126 }
Steven Rostedtae63b312012-05-03 23:09:03 -04001127
1128 dir->tr = tr;
1129
1130 ret = tracing_open_generic(inode, filp);
Steven Rostedt (Red Hat)8e2e2fa2013-07-02 15:30:53 -04001131 if (ret < 0) {
1132 trace_array_put(tr);
Steven Rostedtae63b312012-05-03 23:09:03 -04001133 kfree(dir);
Geyslan G. Bemd6d35232013-11-06 16:02:51 -03001134 return ret;
Steven Rostedt (Red Hat)8e2e2fa2013-07-02 15:30:53 -04001135 }
Steven Rostedtae63b312012-05-03 23:09:03 -04001136
1137 filp->private_data = dir;
Steven Rostedte9dbfae2011-07-05 11:36:06 -04001138
Geyslan G. Bemd6d35232013-11-06 16:02:51 -03001139 return 0;
Steven Rostedte9dbfae2011-07-05 11:36:06 -04001140}
1141
1142static int subsystem_release(struct inode *inode, struct file *file)
1143{
Steven Rostedtae63b312012-05-03 23:09:03 -04001144 struct ftrace_subsystem_dir *dir = file->private_data;
Steven Rostedte9dbfae2011-07-05 11:36:06 -04001145
Steven Rostedt (Red Hat)8e2e2fa2013-07-02 15:30:53 -04001146 trace_array_put(dir->tr);
1147
Steven Rostedtae63b312012-05-03 23:09:03 -04001148 /*
1149 * If dir->subsystem is NULL, then this is a temporary
1150 * descriptor that was made for a trace_array to enable
1151 * all subsystems.
1152 */
1153 if (dir->subsystem)
1154 put_system(dir);
1155 else
1156 kfree(dir);
Steven Rostedte9dbfae2011-07-05 11:36:06 -04001157
1158 return 0;
1159}
1160
Tom Zanussicfb180f2009-03-22 03:31:17 -05001161static ssize_t
1162subsystem_filter_read(struct file *filp, char __user *ubuf, size_t cnt,
1163 loff_t *ppos)
1164{
Steven Rostedtae63b312012-05-03 23:09:03 -04001165 struct ftrace_subsystem_dir *dir = filp->private_data;
1166 struct event_subsystem *system = dir->subsystem;
Tom Zanussicfb180f2009-03-22 03:31:17 -05001167 struct trace_seq *s;
1168 int r;
1169
1170 if (*ppos)
1171 return 0;
1172
1173 s = kmalloc(sizeof(*s), GFP_KERNEL);
1174 if (!s)
1175 return -ENOMEM;
1176
1177 trace_seq_init(s);
1178
Tom Zanussi8b372562009-04-28 03:04:59 -05001179 print_subsystem_event_filter(system, s);
Tom Zanussi4bda2d52009-03-24 02:14:31 -05001180 r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, s->len);
Tom Zanussicfb180f2009-03-22 03:31:17 -05001181
1182 kfree(s);
1183
1184 return r;
1185}
1186
1187static ssize_t
1188subsystem_filter_write(struct file *filp, const char __user *ubuf, size_t cnt,
1189 loff_t *ppos)
1190{
Steven Rostedtae63b312012-05-03 23:09:03 -04001191 struct ftrace_subsystem_dir *dir = filp->private_data;
Tom Zanussi8b372562009-04-28 03:04:59 -05001192 char *buf;
Tom Zanussicfb180f2009-03-22 03:31:17 -05001193 int err;
1194
Tom Zanussi8b372562009-04-28 03:04:59 -05001195 if (cnt >= PAGE_SIZE)
Tom Zanussicfb180f2009-03-22 03:31:17 -05001196 return -EINVAL;
1197
Tom Zanussi8b372562009-04-28 03:04:59 -05001198 buf = (char *)__get_free_page(GFP_TEMPORARY);
1199 if (!buf)
Tom Zanussicfb180f2009-03-22 03:31:17 -05001200 return -ENOMEM;
1201
Tom Zanussi8b372562009-04-28 03:04:59 -05001202 if (copy_from_user(buf, ubuf, cnt)) {
1203 free_page((unsigned long) buf);
1204 return -EFAULT;
Tom Zanussicfb180f2009-03-22 03:31:17 -05001205 }
Tom Zanussi8b372562009-04-28 03:04:59 -05001206 buf[cnt] = '\0';
Tom Zanussicfb180f2009-03-22 03:31:17 -05001207
Steven Rostedtae63b312012-05-03 23:09:03 -04001208 err = apply_subsystem_event_filter(dir, buf);
Tom Zanussi8b372562009-04-28 03:04:59 -05001209 free_page((unsigned long) buf);
1210 if (err < 0)
Li Zefan44e9c8b2009-04-11 15:55:28 +08001211 return err;
Tom Zanussicfb180f2009-03-22 03:31:17 -05001212
1213 *ppos += cnt;
1214
1215 return cnt;
1216}
1217
Steven Rostedtd1b182a2009-04-15 16:53:47 -04001218static ssize_t
1219show_header(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos)
1220{
1221 int (*func)(struct trace_seq *s) = filp->private_data;
1222 struct trace_seq *s;
1223 int r;
1224
1225 if (*ppos)
1226 return 0;
1227
1228 s = kmalloc(sizeof(*s), GFP_KERNEL);
1229 if (!s)
1230 return -ENOMEM;
1231
1232 trace_seq_init(s);
1233
1234 func(s);
1235 r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, s->len);
1236
1237 kfree(s);
1238
1239 return r;
1240}
1241
Steven Rostedt15075ca2012-05-03 14:57:28 -04001242static int ftrace_event_avail_open(struct inode *inode, struct file *file);
1243static int ftrace_event_set_open(struct inode *inode, struct file *file);
Alexander Z Lamf77d09a2013-07-18 11:18:44 -07001244static int ftrace_event_release(struct inode *inode, struct file *file);
Steven Rostedt15075ca2012-05-03 14:57:28 -04001245
Steven Rostedtb77e38a2009-02-24 10:21:36 -05001246static const struct seq_operations show_event_seq_ops = {
1247 .start = t_start,
1248 .next = t_next,
1249 .show = t_show,
1250 .stop = t_stop,
1251};
1252
1253static const struct seq_operations show_set_event_seq_ops = {
1254 .start = s_start,
1255 .next = s_next,
1256 .show = t_show,
1257 .stop = t_stop,
1258};
1259
Steven Rostedt2314c4a2009-03-10 12:04:02 -04001260static const struct file_operations ftrace_avail_fops = {
Steven Rostedt15075ca2012-05-03 14:57:28 -04001261 .open = ftrace_event_avail_open,
Steven Rostedt2314c4a2009-03-10 12:04:02 -04001262 .read = seq_read,
1263 .llseek = seq_lseek,
1264 .release = seq_release,
1265};
1266
Steven Rostedtb77e38a2009-02-24 10:21:36 -05001267static const struct file_operations ftrace_set_event_fops = {
Steven Rostedt15075ca2012-05-03 14:57:28 -04001268 .open = ftrace_event_set_open,
Steven Rostedtb77e38a2009-02-24 10:21:36 -05001269 .read = seq_read,
1270 .write = ftrace_event_write,
1271 .llseek = seq_lseek,
Alexander Z Lamf77d09a2013-07-18 11:18:44 -07001272 .release = ftrace_event_release,
Steven Rostedtb77e38a2009-02-24 10:21:36 -05001273};
1274
Steven Rostedt1473e442009-02-24 14:15:08 -05001275static const struct file_operations ftrace_enable_fops = {
Oleg Nesterovbf682c32013-07-28 20:35:27 +02001276 .open = tracing_open_generic,
Steven Rostedt1473e442009-02-24 14:15:08 -05001277 .read = event_enable_read,
1278 .write = event_enable_write,
Arnd Bergmann6038f372010-08-15 18:52:59 +02001279 .llseek = default_llseek,
Steven Rostedt1473e442009-02-24 14:15:08 -05001280};
1281
Steven Rostedt981d0812009-03-02 13:53:59 -05001282static const struct file_operations ftrace_event_format_fops = {
Steven Rostedt2a37a3d2010-06-03 15:21:34 -04001283 .open = trace_format_open,
1284 .read = seq_read,
1285 .llseek = seq_lseek,
1286 .release = seq_release,
Steven Rostedt981d0812009-03-02 13:53:59 -05001287};
1288
Peter Zijlstra23725ae2009-03-19 20:26:13 +01001289static const struct file_operations ftrace_event_id_fops = {
Peter Zijlstra23725ae2009-03-19 20:26:13 +01001290 .read = event_id_read,
Arnd Bergmann6038f372010-08-15 18:52:59 +02001291 .llseek = default_llseek,
Peter Zijlstra23725ae2009-03-19 20:26:13 +01001292};
1293
Tom Zanussi7ce7e422009-03-22 03:31:04 -05001294static const struct file_operations ftrace_event_filter_fops = {
1295 .open = tracing_open_generic,
1296 .read = event_filter_read,
1297 .write = event_filter_write,
Arnd Bergmann6038f372010-08-15 18:52:59 +02001298 .llseek = default_llseek,
Tom Zanussi7ce7e422009-03-22 03:31:04 -05001299};
1300
Tom Zanussicfb180f2009-03-22 03:31:17 -05001301static const struct file_operations ftrace_subsystem_filter_fops = {
Steven Rostedte9dbfae2011-07-05 11:36:06 -04001302 .open = subsystem_open,
Tom Zanussicfb180f2009-03-22 03:31:17 -05001303 .read = subsystem_filter_read,
1304 .write = subsystem_filter_write,
Arnd Bergmann6038f372010-08-15 18:52:59 +02001305 .llseek = default_llseek,
Steven Rostedte9dbfae2011-07-05 11:36:06 -04001306 .release = subsystem_release,
Tom Zanussicfb180f2009-03-22 03:31:17 -05001307};
1308
Steven Rostedt8ae79a12009-05-06 22:52:15 -04001309static const struct file_operations ftrace_system_enable_fops = {
Steven Rostedt40ee4df2011-07-05 14:32:51 -04001310 .open = subsystem_open,
Steven Rostedt8ae79a12009-05-06 22:52:15 -04001311 .read = system_enable_read,
1312 .write = system_enable_write,
Arnd Bergmann6038f372010-08-15 18:52:59 +02001313 .llseek = default_llseek,
Steven Rostedt40ee4df2011-07-05 14:32:51 -04001314 .release = subsystem_release,
Steven Rostedt8ae79a12009-05-06 22:52:15 -04001315};
1316
Steven Rostedtae63b312012-05-03 23:09:03 -04001317static const struct file_operations ftrace_tr_enable_fops = {
1318 .open = system_tr_open,
1319 .read = system_enable_read,
1320 .write = system_enable_write,
1321 .llseek = default_llseek,
1322 .release = subsystem_release,
1323};
1324
Steven Rostedtd1b182a2009-04-15 16:53:47 -04001325static const struct file_operations ftrace_show_header_fops = {
1326 .open = tracing_open_generic,
1327 .read = show_header,
Arnd Bergmann6038f372010-08-15 18:52:59 +02001328 .llseek = default_llseek,
Steven Rostedtd1b182a2009-04-15 16:53:47 -04001329};
1330
Steven Rostedtae63b312012-05-03 23:09:03 -04001331static int
1332ftrace_event_open(struct inode *inode, struct file *file,
1333 const struct seq_operations *seq_ops)
Steven Rostedt1473e442009-02-24 14:15:08 -05001334{
Steven Rostedtae63b312012-05-03 23:09:03 -04001335 struct seq_file *m;
1336 int ret;
Steven Rostedt1473e442009-02-24 14:15:08 -05001337
Steven Rostedtae63b312012-05-03 23:09:03 -04001338 ret = seq_open(file, seq_ops);
1339 if (ret < 0)
1340 return ret;
1341 m = file->private_data;
1342 /* copy tr over to seq ops */
1343 m->private = inode->i_private;
Steven Rostedt1473e442009-02-24 14:15:08 -05001344
Steven Rostedtae63b312012-05-03 23:09:03 -04001345 return ret;
Steven Rostedt1473e442009-02-24 14:15:08 -05001346}
1347
Alexander Z Lamf77d09a2013-07-18 11:18:44 -07001348static int ftrace_event_release(struct inode *inode, struct file *file)
1349{
1350 struct trace_array *tr = inode->i_private;
1351
1352 trace_array_put(tr);
1353
1354 return seq_release(inode, file);
1355}
1356
Steven Rostedt15075ca2012-05-03 14:57:28 -04001357static int
1358ftrace_event_avail_open(struct inode *inode, struct file *file)
1359{
1360 const struct seq_operations *seq_ops = &show_event_seq_ops;
1361
Steven Rostedtae63b312012-05-03 23:09:03 -04001362 return ftrace_event_open(inode, file, seq_ops);
Steven Rostedt15075ca2012-05-03 14:57:28 -04001363}
1364
1365static int
1366ftrace_event_set_open(struct inode *inode, struct file *file)
1367{
1368 const struct seq_operations *seq_ops = &show_set_event_seq_ops;
Steven Rostedtae63b312012-05-03 23:09:03 -04001369 struct trace_array *tr = inode->i_private;
Alexander Z Lamf77d09a2013-07-18 11:18:44 -07001370 int ret;
1371
1372 if (trace_array_get(tr) < 0)
1373 return -ENODEV;
Steven Rostedt15075ca2012-05-03 14:57:28 -04001374
1375 if ((file->f_mode & FMODE_WRITE) &&
1376 (file->f_flags & O_TRUNC))
Steven Rostedtae63b312012-05-03 23:09:03 -04001377 ftrace_clear_events(tr);
Steven Rostedt15075ca2012-05-03 14:57:28 -04001378
Alexander Z Lamf77d09a2013-07-18 11:18:44 -07001379 ret = ftrace_event_open(inode, file, seq_ops);
1380 if (ret < 0)
1381 trace_array_put(tr);
1382 return ret;
Steven Rostedt15075ca2012-05-03 14:57:28 -04001383}
1384
Steven Rostedtae63b312012-05-03 23:09:03 -04001385static struct event_subsystem *
1386create_new_subsystem(const char *name)
Steven Rostedt6ecc2d12009-02-27 21:33:02 -05001387{
1388 struct event_subsystem *system;
Steven Rostedt6ecc2d12009-02-27 21:33:02 -05001389
1390 /* need to create new entry */
1391 system = kmalloc(sizeof(*system), GFP_KERNEL);
Steven Rostedtae63b312012-05-03 23:09:03 -04001392 if (!system)
1393 return NULL;
Steven Rostedt6ecc2d12009-02-27 21:33:02 -05001394
Steven Rostedte9dbfae2011-07-05 11:36:06 -04001395 system->ref_count = 1;
Steven Rostedt6e94a782013-06-27 10:58:31 -04001396
1397 /* Only allocate if dynamic (kprobes and modules) */
1398 if (!core_kernel_data((unsigned long)name)) {
1399 system->ref_count |= SYSTEM_FL_FREE_NAME;
1400 system->name = kstrdup(name, GFP_KERNEL);
1401 if (!system->name)
1402 goto out_free;
1403 } else
1404 system->name = name;
Steven Rostedt6ecc2d12009-02-27 21:33:02 -05001405
Tom Zanussi30e673b2009-04-28 03:04:47 -05001406 system->filter = NULL;
Tom Zanussicfb180f2009-03-22 03:31:17 -05001407
Tom Zanussi8b372562009-04-28 03:04:59 -05001408 system->filter = kzalloc(sizeof(struct event_filter), GFP_KERNEL);
Steven Rostedtae63b312012-05-03 23:09:03 -04001409 if (!system->filter)
1410 goto out_free;
1411
1412 list_add(&system->list, &event_subsystems);
1413
1414 return system;
1415
1416 out_free:
Steven Rostedt6e94a782013-06-27 10:58:31 -04001417 if (system->ref_count & SYSTEM_FL_FREE_NAME)
1418 kfree(system->name);
Steven Rostedtae63b312012-05-03 23:09:03 -04001419 kfree(system);
1420 return NULL;
1421}
1422
1423static struct dentry *
1424event_subsystem_dir(struct trace_array *tr, const char *name,
1425 struct ftrace_event_file *file, struct dentry *parent)
1426{
1427 struct ftrace_subsystem_dir *dir;
1428 struct event_subsystem *system;
1429 struct dentry *entry;
1430
1431 /* First see if we did not already create this dir */
1432 list_for_each_entry(dir, &tr->systems, list) {
1433 system = dir->subsystem;
1434 if (strcmp(system->name, name) == 0) {
1435 dir->nr_events++;
1436 file->system = dir;
1437 return dir->entry;
1438 }
Tom Zanussi8b372562009-04-28 03:04:59 -05001439 }
1440
Steven Rostedtae63b312012-05-03 23:09:03 -04001441 /* Now see if the system itself exists. */
1442 list_for_each_entry(system, &event_subsystems, list) {
1443 if (strcmp(system->name, name) == 0)
1444 break;
1445 }
1446 /* Reset system variable when not found */
1447 if (&system->list == &event_subsystems)
1448 system = NULL;
1449
1450 dir = kmalloc(sizeof(*dir), GFP_KERNEL);
1451 if (!dir)
1452 goto out_fail;
1453
1454 if (!system) {
1455 system = create_new_subsystem(name);
1456 if (!system)
1457 goto out_free;
1458 } else
1459 __get_system(system);
1460
1461 dir->entry = debugfs_create_dir(name, parent);
1462 if (!dir->entry) {
1463 pr_warning("Failed to create system directory %s\n", name);
1464 __put_system(system);
1465 goto out_free;
1466 }
1467
1468 dir->tr = tr;
1469 dir->ref_count = 1;
1470 dir->nr_events = 1;
1471 dir->subsystem = system;
1472 file->system = dir;
1473
1474 entry = debugfs_create_file("filter", 0644, dir->entry, dir,
Tom Zanussie1112b42009-03-31 00:48:49 -05001475 &ftrace_subsystem_filter_fops);
Tom Zanussi8b372562009-04-28 03:04:59 -05001476 if (!entry) {
1477 kfree(system->filter);
1478 system->filter = NULL;
Steven Rostedtae63b312012-05-03 23:09:03 -04001479 pr_warning("Could not create debugfs '%s/filter' entry\n", name);
Tom Zanussi8b372562009-04-28 03:04:59 -05001480 }
Tom Zanussie1112b42009-03-31 00:48:49 -05001481
Steven Rostedtae63b312012-05-03 23:09:03 -04001482 trace_create_file("enable", 0644, dir->entry, dir,
Frederic Weisbeckerf3f3f002009-09-24 15:27:41 +02001483 &ftrace_system_enable_fops);
Steven Rostedt8ae79a12009-05-06 22:52:15 -04001484
Steven Rostedtae63b312012-05-03 23:09:03 -04001485 list_add(&dir->list, &tr->systems);
1486
1487 return dir->entry;
1488
1489 out_free:
1490 kfree(dir);
1491 out_fail:
1492 /* Only print this message if failed on memory allocation */
1493 if (!dir || !system)
1494 pr_warning("No memory to create event subsystem %s\n",
1495 name);
1496 return NULL;
Steven Rostedt6ecc2d12009-02-27 21:33:02 -05001497}
1498
Steven Rostedt1473e442009-02-24 14:15:08 -05001499static int
Oleg Nesterov620a30e2013-07-31 19:31:35 +02001500event_create_dir(struct dentry *parent, struct ftrace_event_file *file)
Steven Rostedt1473e442009-02-24 14:15:08 -05001501{
Steven Rostedtae63b312012-05-03 23:09:03 -04001502 struct ftrace_event_call *call = file->event_call;
1503 struct trace_array *tr = file->tr;
Steven Rostedt2e33af02010-04-22 10:35:55 -04001504 struct list_head *head;
Steven Rostedtae63b312012-05-03 23:09:03 -04001505 struct dentry *d_events;
Steven Rostedtfd994982009-02-28 02:41:25 -05001506 int ret;
Steven Rostedt1473e442009-02-24 14:15:08 -05001507
Steven Rostedt6ecc2d12009-02-27 21:33:02 -05001508 /*
1509 * If the trace point header did not define TRACE_SYSTEM
1510 * then the system would be called "TRACE_SYSTEM".
1511 */
Steven Rostedtae63b312012-05-03 23:09:03 -04001512 if (strcmp(call->class->system, TRACE_SYSTEM) != 0) {
1513 d_events = event_subsystem_dir(tr, call->class->system, file, parent);
1514 if (!d_events)
1515 return -ENOMEM;
1516 } else
1517 d_events = parent;
Steven Rostedt6ecc2d12009-02-27 21:33:02 -05001518
Steven Rostedtae63b312012-05-03 23:09:03 -04001519 file->dir = debugfs_create_dir(call->name, d_events);
1520 if (!file->dir) {
1521 pr_warning("Could not create debugfs '%s' directory\n",
1522 call->name);
Steven Rostedt1473e442009-02-24 14:15:08 -05001523 return -1;
1524 }
1525
Steven Rostedt9b637762012-05-10 15:55:43 -04001526 if (call->class->reg && !(call->flags & TRACE_EVENT_FL_IGNORE_ENABLE))
Steven Rostedtae63b312012-05-03 23:09:03 -04001527 trace_create_file("enable", 0644, file->dir, file,
Oleg Nesterov620a30e2013-07-31 19:31:35 +02001528 &ftrace_enable_fops);
Steven Rostedt1473e442009-02-24 14:15:08 -05001529
Steven Rostedt22392912010-04-21 12:27:06 -04001530#ifdef CONFIG_PERF_EVENTS
Steven Rostedta1d0ce82010-06-08 11:22:06 -04001531 if (call->event.type && call->class->reg)
Oleg Nesterov1a111262013-07-26 19:25:32 +02001532 trace_create_file("id", 0444, file->dir,
Oleg Nesterov620a30e2013-07-31 19:31:35 +02001533 (void *)(long)call->event.type,
1534 &ftrace_event_id_fops);
Steven Rostedt22392912010-04-21 12:27:06 -04001535#endif
Peter Zijlstra23725ae2009-03-19 20:26:13 +01001536
Li Zefanc9d932c2010-05-24 16:24:28 +08001537 /*
1538 * Other events may have the same class. Only update
1539 * the fields if they are not already defined.
1540 */
1541 head = trace_get_fields(call);
1542 if (list_empty(head)) {
1543 ret = call->class->define_fields(call);
1544 if (ret < 0) {
1545 pr_warning("Could not initialize trace point"
1546 " events/%s\n", call->name);
Steven Rostedtae63b312012-05-03 23:09:03 -04001547 return -1;
Tom Zanussicf027f62009-03-22 03:30:39 -05001548 }
1549 }
Tom Zanussif306cc82013-10-24 08:34:17 -05001550 trace_create_file("filter", 0644, file->dir, file,
Oleg Nesterov620a30e2013-07-31 19:31:35 +02001551 &ftrace_event_filter_fops);
Tom Zanussicf027f62009-03-22 03:30:39 -05001552
Tom Zanussi85f2b082013-10-24 08:59:24 -05001553 trace_create_file("trigger", 0644, file->dir, file,
1554 &event_trigger_fops);
1555
Steven Rostedtae63b312012-05-03 23:09:03 -04001556 trace_create_file("format", 0444, file->dir, call,
Oleg Nesterov620a30e2013-07-31 19:31:35 +02001557 &ftrace_event_format_fops);
Steven Rostedtfd994982009-02-28 02:41:25 -05001558
Steven Rostedt1473e442009-02-24 14:15:08 -05001559 return 0;
1560}
1561
Steven Rostedtae63b312012-05-03 23:09:03 -04001562static void remove_event_from_tracers(struct ftrace_event_call *call)
1563{
1564 struct ftrace_event_file *file;
1565 struct trace_array *tr;
1566
1567 do_for_each_event_file_safe(tr, file) {
Steven Rostedtae63b312012-05-03 23:09:03 -04001568 if (file->event_call != call)
1569 continue;
1570
Oleg Nesterovf6a84bd2013-07-26 19:25:47 +02001571 remove_event_file_dir(file);
Steven Rostedtae63b312012-05-03 23:09:03 -04001572 /*
1573 * The do_for_each_event_file_safe() is
1574 * a double loop. After finding the call for this
1575 * trace_array, we use break to jump to the next
1576 * trace_array.
1577 */
1578 break;
1579 } while_for_each_event_file();
1580}
1581
Ezequiel Garcia87819152012-09-12 11:47:57 -03001582static void event_remove(struct ftrace_event_call *call)
1583{
Steven Rostedtae63b312012-05-03 23:09:03 -04001584 struct trace_array *tr;
1585 struct ftrace_event_file *file;
1586
1587 do_for_each_event_file(tr, file) {
1588 if (file->event_call != call)
1589 continue;
1590 ftrace_event_enable_disable(file, 0);
Tom Zanussif306cc82013-10-24 08:34:17 -05001591 destroy_preds(file);
Steven Rostedtae63b312012-05-03 23:09:03 -04001592 /*
1593 * The do_for_each_event_file() is
1594 * a double loop. After finding the call for this
1595 * trace_array, we use break to jump to the next
1596 * trace_array.
1597 */
1598 break;
1599 } while_for_each_event_file();
1600
Ezequiel Garcia87819152012-09-12 11:47:57 -03001601 if (call->event.funcs)
1602 __unregister_ftrace_event(&call->event);
Steven Rostedtae63b312012-05-03 23:09:03 -04001603 remove_event_from_tracers(call);
Ezequiel Garcia87819152012-09-12 11:47:57 -03001604 list_del(&call->list);
1605}
1606
1607static int event_init(struct ftrace_event_call *call)
1608{
1609 int ret = 0;
1610
1611 if (WARN_ON(!call->name))
1612 return -EINVAL;
1613
1614 if (call->class->raw_init) {
1615 ret = call->class->raw_init(call);
1616 if (ret < 0 && ret != -ENOSYS)
1617 pr_warn("Could not initialize trace events/%s\n",
1618 call->name);
1619 }
1620
1621 return ret;
1622}
1623
Li Zefan67ead0a2010-05-24 16:25:13 +08001624static int
Steven Rostedtae63b312012-05-03 23:09:03 -04001625__register_event(struct ftrace_event_call *call, struct module *mod)
Masami Hiramatsubd1a5c82009-08-13 16:34:53 -04001626{
Masami Hiramatsubd1a5c82009-08-13 16:34:53 -04001627 int ret;
Steven Rostedt6d723732009-04-10 14:53:50 -04001628
Ezequiel Garcia87819152012-09-12 11:47:57 -03001629 ret = event_init(call);
1630 if (ret < 0)
1631 return ret;
Steven Rostedt701970b2009-04-24 23:11:22 -04001632
Steven Rostedtae63b312012-05-03 23:09:03 -04001633 list_add(&call->list, &ftrace_events);
Li Zefan67ead0a2010-05-24 16:25:13 +08001634 call->mod = mod;
Masami Hiramatsu88f70d72009-09-25 11:20:54 -07001635
Steven Rostedtae63b312012-05-03 23:09:03 -04001636 return 0;
Masami Hiramatsubd1a5c82009-08-13 16:34:53 -04001637}
1638
Steven Rostedt (Red Hat)da511bf2013-05-09 15:00:07 -04001639static struct ftrace_event_file *
1640trace_create_new_event(struct ftrace_event_call *call,
1641 struct trace_array *tr)
1642{
1643 struct ftrace_event_file *file;
1644
1645 file = kmem_cache_alloc(file_cachep, GFP_TRACE);
1646 if (!file)
1647 return NULL;
1648
1649 file->event_call = call;
1650 file->tr = tr;
1651 atomic_set(&file->sm_ref, 0);
Tom Zanussi85f2b082013-10-24 08:59:24 -05001652 atomic_set(&file->tm_ref, 0);
1653 INIT_LIST_HEAD(&file->triggers);
Steven Rostedt (Red Hat)da511bf2013-05-09 15:00:07 -04001654 list_add(&file->list, &tr->events);
1655
1656 return file;
1657}
1658
Steven Rostedtae63b312012-05-03 23:09:03 -04001659/* Add an event to a trace directory */
1660static int
Oleg Nesterov620a30e2013-07-31 19:31:35 +02001661__trace_add_new_event(struct ftrace_event_call *call, struct trace_array *tr)
Steven Rostedtae63b312012-05-03 23:09:03 -04001662{
1663 struct ftrace_event_file *file;
1664
Steven Rostedt (Red Hat)da511bf2013-05-09 15:00:07 -04001665 file = trace_create_new_event(call, tr);
Steven Rostedtae63b312012-05-03 23:09:03 -04001666 if (!file)
1667 return -ENOMEM;
1668
Oleg Nesterov620a30e2013-07-31 19:31:35 +02001669 return event_create_dir(tr->event_dir, file);
Steven Rostedtae63b312012-05-03 23:09:03 -04001670}
1671
Steven Rostedt77248222013-02-27 16:28:06 -05001672/*
1673 * Just create a decriptor for early init. A descriptor is required
1674 * for enabling events at boot. We want to enable events before
1675 * the filesystem is initialized.
1676 */
1677static __init int
1678__trace_early_add_new_event(struct ftrace_event_call *call,
1679 struct trace_array *tr)
1680{
1681 struct ftrace_event_file *file;
1682
Steven Rostedt (Red Hat)da511bf2013-05-09 15:00:07 -04001683 file = trace_create_new_event(call, tr);
Steven Rostedt77248222013-02-27 16:28:06 -05001684 if (!file)
1685 return -ENOMEM;
1686
Steven Rostedt77248222013-02-27 16:28:06 -05001687 return 0;
1688}
1689
Steven Rostedtae63b312012-05-03 23:09:03 -04001690struct ftrace_module_file_ops;
Oleg Nesterov779c5e32013-07-31 19:31:32 +02001691static void __add_event_to_tracers(struct ftrace_event_call *call);
Steven Rostedtae63b312012-05-03 23:09:03 -04001692
Masami Hiramatsubd1a5c82009-08-13 16:34:53 -04001693/* Add an additional event_call dynamically */
1694int trace_add_event_call(struct ftrace_event_call *call)
1695{
1696 int ret;
Alexander Z Lama8227412013-07-01 19:37:54 -07001697 mutex_lock(&trace_types_lock);
Masami Hiramatsubd1a5c82009-08-13 16:34:53 -04001698 mutex_lock(&event_mutex);
Steven Rostedtae63b312012-05-03 23:09:03 -04001699
1700 ret = __register_event(call, NULL);
1701 if (ret >= 0)
Oleg Nesterov779c5e32013-07-31 19:31:32 +02001702 __add_event_to_tracers(call);
Steven Rostedtae63b312012-05-03 23:09:03 -04001703
Masami Hiramatsubd1a5c82009-08-13 16:34:53 -04001704 mutex_unlock(&event_mutex);
Alexander Z Lama8227412013-07-01 19:37:54 -07001705 mutex_unlock(&trace_types_lock);
Masami Hiramatsubd1a5c82009-08-13 16:34:53 -04001706 return ret;
1707}
Steven Rostedt701970b2009-04-24 23:11:22 -04001708
Masami Hiramatsu4fead8e2009-09-14 16:49:12 -04001709/*
Alexander Z Lama8227412013-07-01 19:37:54 -07001710 * Must be called under locking of trace_types_lock, event_mutex and
1711 * trace_event_sem.
Masami Hiramatsu4fead8e2009-09-14 16:49:12 -04001712 */
Masami Hiramatsubd1a5c82009-08-13 16:34:53 -04001713static void __trace_remove_event_call(struct ftrace_event_call *call)
1714{
Ezequiel Garcia87819152012-09-12 11:47:57 -03001715 event_remove(call);
Masami Hiramatsubd1a5c82009-08-13 16:34:53 -04001716 trace_destroy_fields(call);
Tom Zanussif306cc82013-10-24 08:34:17 -05001717 destroy_call_preds(call);
Masami Hiramatsubd1a5c82009-08-13 16:34:53 -04001718}
1719
Oleg Nesterov2816c552013-07-29 19:50:33 +02001720static int probe_remove_event_call(struct ftrace_event_call *call)
Masami Hiramatsubd1a5c82009-08-13 16:34:53 -04001721{
Oleg Nesterov2816c552013-07-29 19:50:33 +02001722 struct trace_array *tr;
1723 struct ftrace_event_file *file;
1724
1725#ifdef CONFIG_PERF_EVENTS
1726 if (call->perf_refcount)
1727 return -EBUSY;
1728#endif
1729 do_for_each_event_file(tr, file) {
1730 if (file->event_call != call)
1731 continue;
1732 /*
1733 * We can't rely on ftrace_event_enable_disable(enable => 0)
1734 * we are going to do, FTRACE_EVENT_FL_SOFT_MODE can suppress
1735 * TRACE_REG_UNREGISTER.
1736 */
1737 if (file->flags & FTRACE_EVENT_FL_ENABLED)
1738 return -EBUSY;
Steven Rostedt (Red Hat)2ba64032013-07-31 13:16:22 -04001739 /*
1740 * The do_for_each_event_file_safe() is
1741 * a double loop. After finding the call for this
1742 * trace_array, we use break to jump to the next
1743 * trace_array.
1744 */
Oleg Nesterov2816c552013-07-29 19:50:33 +02001745 break;
1746 } while_for_each_event_file();
1747
1748 __trace_remove_event_call(call);
1749
1750 return 0;
1751}
1752
1753/* Remove an event_call */
1754int trace_remove_event_call(struct ftrace_event_call *call)
1755{
1756 int ret;
1757
Alexander Z Lama8227412013-07-01 19:37:54 -07001758 mutex_lock(&trace_types_lock);
Masami Hiramatsubd1a5c82009-08-13 16:34:53 -04001759 mutex_lock(&event_mutex);
zhangwei(Jovi)52f6ad62013-03-11 15:14:03 +08001760 down_write(&trace_event_sem);
Oleg Nesterov2816c552013-07-29 19:50:33 +02001761 ret = probe_remove_event_call(call);
zhangwei(Jovi)52f6ad62013-03-11 15:14:03 +08001762 up_write(&trace_event_sem);
Masami Hiramatsubd1a5c82009-08-13 16:34:53 -04001763 mutex_unlock(&event_mutex);
Alexander Z Lama8227412013-07-01 19:37:54 -07001764 mutex_unlock(&trace_types_lock);
Oleg Nesterov2816c552013-07-29 19:50:33 +02001765
1766 return ret;
Masami Hiramatsubd1a5c82009-08-13 16:34:53 -04001767}
1768
1769#define for_each_event(event, start, end) \
1770 for (event = start; \
1771 (unsigned long)event < (unsigned long)end; \
1772 event++)
1773
1774#ifdef CONFIG_MODULES
1775
Steven Rostedt6d723732009-04-10 14:53:50 -04001776static void trace_module_add_events(struct module *mod)
1777{
Steven Rostedte4a9ea52011-01-27 09:15:30 -05001778 struct ftrace_event_call **call, **start, **end;
Steven Rostedt6d723732009-04-10 14:53:50 -04001779
Steven Rostedt (Red Hat)45ab28132014-02-26 13:37:38 -05001780 if (!mod->num_trace_events)
1781 return;
1782
1783 /* Don't add infrastructure for mods without tracepoints */
1784 if (trace_module_has_bad_taint(mod)) {
1785 pr_err("%s: module has bad taint, not creating trace events\n",
1786 mod->name);
1787 return;
1788 }
1789
Steven Rostedt6d723732009-04-10 14:53:50 -04001790 start = mod->trace_events;
1791 end = mod->trace_events + mod->num_trace_events;
1792
Steven Rostedt6d723732009-04-10 14:53:50 -04001793 for_each_event(call, start, end) {
Steven Rostedtae63b312012-05-03 23:09:03 -04001794 __register_event(*call, mod);
Oleg Nesterov779c5e32013-07-31 19:31:32 +02001795 __add_event_to_tracers(*call);
Steven Rostedt6d723732009-04-10 14:53:50 -04001796 }
1797}
1798
1799static void trace_module_remove_events(struct module *mod)
1800{
1801 struct ftrace_event_call *call, *p;
Steven Rostedt (Red Hat)575380d2013-03-04 23:05:12 -05001802 bool clear_trace = false;
Steven Rostedt6d723732009-04-10 14:53:50 -04001803
zhangwei(Jovi)52f6ad62013-03-11 15:14:03 +08001804 down_write(&trace_event_sem);
Steven Rostedt6d723732009-04-10 14:53:50 -04001805 list_for_each_entry_safe(call, p, &ftrace_events, list) {
1806 if (call->mod == mod) {
Steven Rostedt (Red Hat)575380d2013-03-04 23:05:12 -05001807 if (call->flags & TRACE_EVENT_FL_WAS_ENABLED)
1808 clear_trace = true;
Masami Hiramatsubd1a5c82009-08-13 16:34:53 -04001809 __trace_remove_event_call(call);
Steven Rostedt6d723732009-04-10 14:53:50 -04001810 }
1811 }
zhangwei(Jovi)52f6ad62013-03-11 15:14:03 +08001812 up_write(&trace_event_sem);
Steven Rostedt9456f0f2009-05-06 21:54:09 -04001813
1814 /*
1815 * It is safest to reset the ring buffer if the module being unloaded
Steven Rostedt (Red Hat)873c6422013-03-04 23:26:06 -05001816 * registered any events that were used. The only worry is if
1817 * a new module gets loaded, and takes on the same id as the events
1818 * of this module. When printing out the buffer, traced events left
1819 * over from this module may be passed to the new module events and
1820 * unexpected results may occur.
Steven Rostedt9456f0f2009-05-06 21:54:09 -04001821 */
Steven Rostedt (Red Hat)575380d2013-03-04 23:05:12 -05001822 if (clear_trace)
Steven Rostedt (Red Hat)873c6422013-03-04 23:26:06 -05001823 tracing_reset_all_online_cpus();
Steven Rostedt6d723732009-04-10 14:53:50 -04001824}
1825
Steven Rostedt61f919a2009-04-14 18:22:32 -04001826static int trace_module_notify(struct notifier_block *self,
1827 unsigned long val, void *data)
Steven Rostedt6d723732009-04-10 14:53:50 -04001828{
1829 struct module *mod = data;
1830
Alexander Z Lama8227412013-07-01 19:37:54 -07001831 mutex_lock(&trace_types_lock);
Steven Rostedt6d723732009-04-10 14:53:50 -04001832 mutex_lock(&event_mutex);
1833 switch (val) {
1834 case MODULE_STATE_COMING:
1835 trace_module_add_events(mod);
1836 break;
1837 case MODULE_STATE_GOING:
1838 trace_module_remove_events(mod);
1839 break;
1840 }
1841 mutex_unlock(&event_mutex);
Alexander Z Lama8227412013-07-01 19:37:54 -07001842 mutex_unlock(&trace_types_lock);
Steven Rostedt6d723732009-04-10 14:53:50 -04001843
1844 return 0;
1845}
Steven Rostedt (Red Hat)315326c2013-03-02 17:37:14 -05001846
Oleg Nesterov836d4812013-07-31 19:31:37 +02001847static struct notifier_block trace_module_nb = {
1848 .notifier_call = trace_module_notify,
1849 .priority = 0,
1850};
Steven Rostedt61f919a2009-04-14 18:22:32 -04001851#endif /* CONFIG_MODULES */
Steven Rostedt6d723732009-04-10 14:53:50 -04001852
Steven Rostedtae63b312012-05-03 23:09:03 -04001853/* Create a new event directory structure for a trace directory. */
1854static void
1855__trace_add_event_dirs(struct trace_array *tr)
1856{
Steven Rostedtae63b312012-05-03 23:09:03 -04001857 struct ftrace_event_call *call;
1858 int ret;
1859
1860 list_for_each_entry(call, &ftrace_events, list) {
Oleg Nesterov620a30e2013-07-31 19:31:35 +02001861 ret = __trace_add_new_event(call, tr);
Steven Rostedtae63b312012-05-03 23:09:03 -04001862 if (ret < 0)
1863 pr_warning("Could not create directory for event %s\n",
1864 call->name);
1865 }
1866}
1867
Tom Zanussi7862ad12013-10-24 08:59:28 -05001868struct ftrace_event_file *
Steven Rostedt (Red Hat)3cd715d2013-03-12 19:35:13 -04001869find_event_file(struct trace_array *tr, const char *system, const char *event)
1870{
1871 struct ftrace_event_file *file;
1872 struct ftrace_event_call *call;
1873
1874 list_for_each_entry(file, &tr->events, list) {
1875
1876 call = file->event_call;
1877
1878 if (!call->name || !call->class || !call->class->reg)
1879 continue;
1880
1881 if (call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)
1882 continue;
1883
1884 if (strcmp(event, call->name) == 0 &&
1885 strcmp(system, call->class->system) == 0)
1886 return file;
1887 }
1888 return NULL;
1889}
1890
Steven Rostedt (Red Hat)2875a082013-12-20 23:23:05 -05001891#ifdef CONFIG_DYNAMIC_FTRACE
1892
1893/* Avoid typos */
1894#define ENABLE_EVENT_STR "enable_event"
1895#define DISABLE_EVENT_STR "disable_event"
1896
1897struct event_probe_data {
1898 struct ftrace_event_file *file;
1899 unsigned long count;
1900 int ref;
1901 bool enable;
1902};
1903
Steven Rostedt (Red Hat)3cd715d2013-03-12 19:35:13 -04001904static void
1905event_enable_probe(unsigned long ip, unsigned long parent_ip, void **_data)
1906{
1907 struct event_probe_data **pdata = (struct event_probe_data **)_data;
1908 struct event_probe_data *data = *pdata;
1909
1910 if (!data)
1911 return;
1912
1913 if (data->enable)
1914 clear_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &data->file->flags);
1915 else
1916 set_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &data->file->flags);
1917}
1918
1919static void
1920event_enable_count_probe(unsigned long ip, unsigned long parent_ip, void **_data)
1921{
1922 struct event_probe_data **pdata = (struct event_probe_data **)_data;
1923 struct event_probe_data *data = *pdata;
1924
1925 if (!data)
1926 return;
1927
1928 if (!data->count)
1929 return;
1930
1931 /* Skip if the event is in a state we want to switch to */
1932 if (data->enable == !(data->file->flags & FTRACE_EVENT_FL_SOFT_DISABLED))
1933 return;
1934
1935 if (data->count != -1)
1936 (data->count)--;
1937
1938 event_enable_probe(ip, parent_ip, _data);
1939}
1940
1941static int
1942event_enable_print(struct seq_file *m, unsigned long ip,
1943 struct ftrace_probe_ops *ops, void *_data)
1944{
1945 struct event_probe_data *data = _data;
1946
1947 seq_printf(m, "%ps:", (void *)ip);
1948
1949 seq_printf(m, "%s:%s:%s",
1950 data->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR,
1951 data->file->event_call->class->system,
1952 data->file->event_call->name);
1953
1954 if (data->count == -1)
1955 seq_printf(m, ":unlimited\n");
1956 else
1957 seq_printf(m, ":count=%ld\n", data->count);
1958
1959 return 0;
1960}
1961
1962static int
1963event_enable_init(struct ftrace_probe_ops *ops, unsigned long ip,
1964 void **_data)
1965{
1966 struct event_probe_data **pdata = (struct event_probe_data **)_data;
1967 struct event_probe_data *data = *pdata;
1968
1969 data->ref++;
1970 return 0;
1971}
1972
1973static void
1974event_enable_free(struct ftrace_probe_ops *ops, unsigned long ip,
1975 void **_data)
1976{
1977 struct event_probe_data **pdata = (struct event_probe_data **)_data;
1978 struct event_probe_data *data = *pdata;
1979
1980 if (WARN_ON_ONCE(data->ref <= 0))
1981 return;
1982
1983 data->ref--;
1984 if (!data->ref) {
1985 /* Remove the SOFT_MODE flag */
1986 __ftrace_event_enable_disable(data->file, 0, 1);
1987 module_put(data->file->event_call->mod);
1988 kfree(data);
1989 }
1990 *pdata = NULL;
1991}
1992
1993static struct ftrace_probe_ops event_enable_probe_ops = {
1994 .func = event_enable_probe,
1995 .print = event_enable_print,
1996 .init = event_enable_init,
1997 .free = event_enable_free,
1998};
1999
2000static struct ftrace_probe_ops event_enable_count_probe_ops = {
2001 .func = event_enable_count_probe,
2002 .print = event_enable_print,
2003 .init = event_enable_init,
2004 .free = event_enable_free,
2005};
2006
2007static struct ftrace_probe_ops event_disable_probe_ops = {
2008 .func = event_enable_probe,
2009 .print = event_enable_print,
2010 .init = event_enable_init,
2011 .free = event_enable_free,
2012};
2013
2014static struct ftrace_probe_ops event_disable_count_probe_ops = {
2015 .func = event_enable_count_probe,
2016 .print = event_enable_print,
2017 .init = event_enable_init,
2018 .free = event_enable_free,
2019};
2020
2021static int
2022event_enable_func(struct ftrace_hash *hash,
2023 char *glob, char *cmd, char *param, int enabled)
2024{
2025 struct trace_array *tr = top_trace_array();
2026 struct ftrace_event_file *file;
2027 struct ftrace_probe_ops *ops;
2028 struct event_probe_data *data;
2029 const char *system;
2030 const char *event;
2031 char *number;
2032 bool enable;
2033 int ret;
2034
2035 /* hash funcs only work with set_ftrace_filter */
Harsh Prateek Bora8092e802013-05-24 12:52:17 +05302036 if (!enabled || !param)
Steven Rostedt (Red Hat)3cd715d2013-03-12 19:35:13 -04002037 return -EINVAL;
2038
2039 system = strsep(&param, ":");
2040 if (!param)
2041 return -EINVAL;
2042
2043 event = strsep(&param, ":");
2044
2045 mutex_lock(&event_mutex);
2046
2047 ret = -EINVAL;
2048 file = find_event_file(tr, system, event);
2049 if (!file)
2050 goto out;
2051
2052 enable = strcmp(cmd, ENABLE_EVENT_STR) == 0;
2053
2054 if (enable)
2055 ops = param ? &event_enable_count_probe_ops : &event_enable_probe_ops;
2056 else
2057 ops = param ? &event_disable_count_probe_ops : &event_disable_probe_ops;
2058
2059 if (glob[0] == '!') {
2060 unregister_ftrace_function_probe_func(glob+1, ops);
2061 ret = 0;
2062 goto out;
2063 }
2064
2065 ret = -ENOMEM;
2066 data = kzalloc(sizeof(*data), GFP_KERNEL);
2067 if (!data)
2068 goto out;
2069
2070 data->enable = enable;
2071 data->count = -1;
2072 data->file = file;
2073
2074 if (!param)
2075 goto out_reg;
2076
2077 number = strsep(&param, ":");
2078
2079 ret = -EINVAL;
2080 if (!strlen(number))
2081 goto out_free;
2082
2083 /*
2084 * We use the callback data field (which is a pointer)
2085 * as our counter.
2086 */
2087 ret = kstrtoul(number, 0, &data->count);
2088 if (ret)
2089 goto out_free;
2090
2091 out_reg:
2092 /* Don't let event modules unload while probe registered */
2093 ret = try_module_get(file->event_call->mod);
Masami Hiramatsu6ed01062013-05-16 20:48:49 +09002094 if (!ret) {
2095 ret = -EBUSY;
Steven Rostedt (Red Hat)3cd715d2013-03-12 19:35:13 -04002096 goto out_free;
Masami Hiramatsu6ed01062013-05-16 20:48:49 +09002097 }
Steven Rostedt (Red Hat)3cd715d2013-03-12 19:35:13 -04002098
2099 ret = __ftrace_event_enable_disable(file, 1, 1);
2100 if (ret < 0)
2101 goto out_put;
2102 ret = register_ftrace_function_probe(glob, ops, data);
Steven Rostedt (Red Hat)ff305de2013-05-09 11:30:26 -04002103 /*
2104 * The above returns on success the # of functions enabled,
2105 * but if it didn't find any functions it returns zero.
2106 * Consider no functions a failure too.
2107 */
Masami Hiramatsua5b85bd2013-05-09 14:44:14 +09002108 if (!ret) {
2109 ret = -ENOENT;
Steven Rostedt (Red Hat)3cd715d2013-03-12 19:35:13 -04002110 goto out_disable;
Steven Rostedt (Red Hat)ff305de2013-05-09 11:30:26 -04002111 } else if (ret < 0)
2112 goto out_disable;
2113 /* Just return zero, not the number of enabled functions */
2114 ret = 0;
Steven Rostedt (Red Hat)3cd715d2013-03-12 19:35:13 -04002115 out:
2116 mutex_unlock(&event_mutex);
2117 return ret;
2118
2119 out_disable:
2120 __ftrace_event_enable_disable(file, 0, 1);
2121 out_put:
2122 module_put(file->event_call->mod);
2123 out_free:
2124 kfree(data);
2125 goto out;
2126}
2127
2128static struct ftrace_func_command event_enable_cmd = {
2129 .name = ENABLE_EVENT_STR,
2130 .func = event_enable_func,
2131};
2132
2133static struct ftrace_func_command event_disable_cmd = {
2134 .name = DISABLE_EVENT_STR,
2135 .func = event_enable_func,
2136};
2137
2138static __init int register_event_cmds(void)
2139{
2140 int ret;
2141
2142 ret = register_ftrace_command(&event_enable_cmd);
2143 if (WARN_ON(ret < 0))
2144 return ret;
2145 ret = register_ftrace_command(&event_disable_cmd);
2146 if (WARN_ON(ret < 0))
2147 unregister_ftrace_command(&event_enable_cmd);
2148 return ret;
2149}
2150#else
2151static inline int register_event_cmds(void) { return 0; }
2152#endif /* CONFIG_DYNAMIC_FTRACE */
2153
Steven Rostedt77248222013-02-27 16:28:06 -05002154/*
2155 * The top level array has already had its ftrace_event_file
2156 * descriptors created in order to allow for early events to
2157 * be recorded. This function is called after the debugfs has been
2158 * initialized, and we now have to create the files associated
2159 * to the events.
2160 */
2161static __init void
2162__trace_early_add_event_dirs(struct trace_array *tr)
2163{
2164 struct ftrace_event_file *file;
2165 int ret;
2166
2167
2168 list_for_each_entry(file, &tr->events, list) {
Oleg Nesterov620a30e2013-07-31 19:31:35 +02002169 ret = event_create_dir(tr->event_dir, file);
Steven Rostedt77248222013-02-27 16:28:06 -05002170 if (ret < 0)
2171 pr_warning("Could not create directory for event %s\n",
2172 file->event_call->name);
2173 }
2174}
2175
2176/*
2177 * For early boot up, the top trace array requires to have
2178 * a list of events that can be enabled. This must be done before
2179 * the filesystem is set up in order to allow events to be traced
2180 * early.
2181 */
2182static __init void
2183__trace_early_add_events(struct trace_array *tr)
2184{
2185 struct ftrace_event_call *call;
2186 int ret;
2187
2188 list_for_each_entry(call, &ftrace_events, list) {
2189 /* Early boot up should not have any modules loaded */
2190 if (WARN_ON_ONCE(call->mod))
2191 continue;
2192
2193 ret = __trace_early_add_new_event(call, tr);
2194 if (ret < 0)
2195 pr_warning("Could not create early event %s\n",
2196 call->name);
2197 }
2198}
2199
Steven Rostedt0c8916c2012-08-07 16:14:16 -04002200/* Remove the event directory structure for a trace directory. */
2201static void
2202__trace_remove_event_dirs(struct trace_array *tr)
2203{
2204 struct ftrace_event_file *file, *next;
2205
Oleg Nesterovf6a84bd2013-07-26 19:25:47 +02002206 list_for_each_entry_safe(file, next, &tr->events, list)
2207 remove_event_file_dir(file);
Steven Rostedt0c8916c2012-08-07 16:14:16 -04002208}
2209
Oleg Nesterov779c5e32013-07-31 19:31:32 +02002210static void __add_event_to_tracers(struct ftrace_event_call *call)
Steven Rostedtae63b312012-05-03 23:09:03 -04002211{
2212 struct trace_array *tr;
2213
Oleg Nesterov620a30e2013-07-31 19:31:35 +02002214 list_for_each_entry(tr, &ftrace_trace_arrays, list)
2215 __trace_add_new_event(call, tr);
Steven Rostedtae63b312012-05-03 23:09:03 -04002216}
2217
Steven Rostedte4a9ea52011-01-27 09:15:30 -05002218extern struct ftrace_event_call *__start_ftrace_events[];
2219extern struct ftrace_event_call *__stop_ftrace_events[];
Steven Rostedta59fd602009-04-10 13:52:20 -04002220
Li Zefan020e5f82009-07-01 10:47:05 +08002221static char bootup_event_buf[COMMAND_LINE_SIZE] __initdata;
2222
2223static __init int setup_trace_event(char *str)
2224{
2225 strlcpy(bootup_event_buf, str, COMMAND_LINE_SIZE);
Steven Rostedt (Red Hat)55034cd2013-03-07 22:48:09 -05002226 ring_buffer_expanded = true;
2227 tracing_selftest_disabled = true;
Li Zefan020e5f82009-07-01 10:47:05 +08002228
2229 return 1;
2230}
2231__setup("trace_event=", setup_trace_event);
2232
Steven Rostedt77248222013-02-27 16:28:06 -05002233/* Expects to have event_mutex held when called */
2234static int
2235create_event_toplevel_files(struct dentry *parent, struct trace_array *tr)
Steven Rostedtae63b312012-05-03 23:09:03 -04002236{
2237 struct dentry *d_events;
2238 struct dentry *entry;
2239
2240 entry = debugfs_create_file("set_event", 0644, parent,
2241 tr, &ftrace_set_event_fops);
2242 if (!entry) {
2243 pr_warning("Could not create debugfs 'set_event' entry\n");
2244 return -ENOMEM;
2245 }
2246
2247 d_events = debugfs_create_dir("events", parent);
Steven Rostedt277ba042012-08-03 16:10:49 -04002248 if (!d_events) {
Steven Rostedtae63b312012-05-03 23:09:03 -04002249 pr_warning("Could not create debugfs 'events' directory\n");
Steven Rostedt277ba042012-08-03 16:10:49 -04002250 return -ENOMEM;
2251 }
Steven Rostedtae63b312012-05-03 23:09:03 -04002252
2253 /* ring buffer internal formats */
2254 trace_create_file("header_page", 0444, d_events,
2255 ring_buffer_print_page_header,
2256 &ftrace_show_header_fops);
2257
2258 trace_create_file("header_event", 0444, d_events,
2259 ring_buffer_print_entry_header,
2260 &ftrace_show_header_fops);
2261
2262 trace_create_file("enable", 0644, d_events,
2263 tr, &ftrace_tr_enable_fops);
2264
2265 tr->event_dir = d_events;
Steven Rostedt77248222013-02-27 16:28:06 -05002266
2267 return 0;
2268}
2269
2270/**
2271 * event_trace_add_tracer - add a instance of a trace_array to events
2272 * @parent: The parent dentry to place the files/directories for events in
2273 * @tr: The trace array associated with these events
2274 *
2275 * When a new instance is created, it needs to set up its events
2276 * directory, as well as other files associated with events. It also
2277 * creates the event hierachry in the @parent/events directory.
2278 *
2279 * Returns 0 on success.
2280 */
2281int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr)
2282{
2283 int ret;
2284
2285 mutex_lock(&event_mutex);
2286
2287 ret = create_event_toplevel_files(parent, tr);
2288 if (ret)
2289 goto out_unlock;
2290
zhangwei(Jovi)52f6ad62013-03-11 15:14:03 +08002291 down_write(&trace_event_sem);
Steven Rostedtae63b312012-05-03 23:09:03 -04002292 __trace_add_event_dirs(tr);
zhangwei(Jovi)52f6ad62013-03-11 15:14:03 +08002293 up_write(&trace_event_sem);
Steven Rostedt277ba042012-08-03 16:10:49 -04002294
Steven Rostedt77248222013-02-27 16:28:06 -05002295 out_unlock:
Steven Rostedt277ba042012-08-03 16:10:49 -04002296 mutex_unlock(&event_mutex);
Steven Rostedtae63b312012-05-03 23:09:03 -04002297
Steven Rostedt77248222013-02-27 16:28:06 -05002298 return ret;
2299}
2300
2301/*
2302 * The top trace array already had its file descriptors created.
2303 * Now the files themselves need to be created.
2304 */
2305static __init int
2306early_event_add_tracer(struct dentry *parent, struct trace_array *tr)
2307{
2308 int ret;
2309
2310 mutex_lock(&event_mutex);
2311
2312 ret = create_event_toplevel_files(parent, tr);
2313 if (ret)
2314 goto out_unlock;
2315
zhangwei(Jovi)52f6ad62013-03-11 15:14:03 +08002316 down_write(&trace_event_sem);
Steven Rostedt77248222013-02-27 16:28:06 -05002317 __trace_early_add_event_dirs(tr);
zhangwei(Jovi)52f6ad62013-03-11 15:14:03 +08002318 up_write(&trace_event_sem);
Steven Rostedt77248222013-02-27 16:28:06 -05002319
2320 out_unlock:
2321 mutex_unlock(&event_mutex);
2322
2323 return ret;
Steven Rostedtae63b312012-05-03 23:09:03 -04002324}
2325
Steven Rostedt0c8916c2012-08-07 16:14:16 -04002326int event_trace_del_tracer(struct trace_array *tr)
2327{
Steven Rostedt0c8916c2012-08-07 16:14:16 -04002328 mutex_lock(&event_mutex);
2329
Tom Zanussi85f2b082013-10-24 08:59:24 -05002330 /* Disable any event triggers and associated soft-disabled events */
2331 clear_event_triggers(tr);
2332
Steven Rostedt (Red Hat)2a6c24a2013-07-02 14:48:23 -04002333 /* Disable any running events */
2334 __ftrace_set_clr_event_nolock(tr, NULL, NULL, NULL, 0);
2335
Steven Rostedt3ccb0122013-12-03 12:41:20 -05002336 /* Access to events are within rcu_read_lock_sched() */
2337 synchronize_sched();
2338
zhangwei(Jovi)52f6ad62013-03-11 15:14:03 +08002339 down_write(&trace_event_sem);
Steven Rostedt0c8916c2012-08-07 16:14:16 -04002340 __trace_remove_event_dirs(tr);
2341 debugfs_remove_recursive(tr->event_dir);
zhangwei(Jovi)52f6ad62013-03-11 15:14:03 +08002342 up_write(&trace_event_sem);
Steven Rostedt0c8916c2012-08-07 16:14:16 -04002343
2344 tr->event_dir = NULL;
2345
2346 mutex_unlock(&event_mutex);
2347
2348 return 0;
2349}
2350
Steven Rostedtd1a29142013-02-27 20:23:57 -05002351static __init int event_trace_memsetup(void)
2352{
2353 field_cachep = KMEM_CACHE(ftrace_event_field, SLAB_PANIC);
2354 file_cachep = KMEM_CACHE(ftrace_event_file, SLAB_PANIC);
2355 return 0;
2356}
2357
Ezequiel Garcia87819152012-09-12 11:47:57 -03002358static __init int event_trace_enable(void)
2359{
Steven Rostedtae63b312012-05-03 23:09:03 -04002360 struct trace_array *tr = top_trace_array();
Ezequiel Garcia87819152012-09-12 11:47:57 -03002361 struct ftrace_event_call **iter, *call;
2362 char *buf = bootup_event_buf;
2363 char *token;
2364 int ret;
2365
2366 for_each_event(iter, __start_ftrace_events, __stop_ftrace_events) {
2367
2368 call = *iter;
2369 ret = event_init(call);
2370 if (!ret)
2371 list_add(&call->list, &ftrace_events);
2372 }
2373
Steven Rostedt77248222013-02-27 16:28:06 -05002374 /*
2375 * We need the top trace array to have a working set of trace
2376 * points at early init, before the debug files and directories
2377 * are created. Create the file entries now, and attach them
2378 * to the actual file dentries later.
2379 */
2380 __trace_early_add_events(tr);
2381
Ezequiel Garcia87819152012-09-12 11:47:57 -03002382 while (true) {
2383 token = strsep(&buf, ",");
2384
2385 if (!token)
2386 break;
2387 if (!*token)
2388 continue;
2389
Steven Rostedtae63b312012-05-03 23:09:03 -04002390 ret = ftrace_set_clr_event(tr, token, 1);
Ezequiel Garcia87819152012-09-12 11:47:57 -03002391 if (ret)
2392 pr_warn("Failed to enable trace event: %s\n", token);
2393 }
Steven Rostedt81698832012-10-11 10:15:05 -04002394
2395 trace_printk_start_comm();
2396
Steven Rostedt (Red Hat)3cd715d2013-03-12 19:35:13 -04002397 register_event_cmds();
2398
Tom Zanussi85f2b082013-10-24 08:59:24 -05002399 register_trigger_cmds();
2400
Ezequiel Garcia87819152012-09-12 11:47:57 -03002401 return 0;
2402}
2403
Steven Rostedtb77e38a2009-02-24 10:21:36 -05002404static __init int event_trace_init(void)
2405{
Steven Rostedtae63b312012-05-03 23:09:03 -04002406 struct trace_array *tr;
Steven Rostedtb77e38a2009-02-24 10:21:36 -05002407 struct dentry *d_tracer;
2408 struct dentry *entry;
Steven Rostedt6d723732009-04-10 14:53:50 -04002409 int ret;
Steven Rostedtb77e38a2009-02-24 10:21:36 -05002410
Steven Rostedtae63b312012-05-03 23:09:03 -04002411 tr = top_trace_array();
2412
Steven Rostedtb77e38a2009-02-24 10:21:36 -05002413 d_tracer = tracing_init_dentry();
2414 if (!d_tracer)
2415 return 0;
2416
Steven Rostedt2314c4a2009-03-10 12:04:02 -04002417 entry = debugfs_create_file("available_events", 0444, d_tracer,
Steven Rostedtae63b312012-05-03 23:09:03 -04002418 tr, &ftrace_avail_fops);
Steven Rostedt2314c4a2009-03-10 12:04:02 -04002419 if (!entry)
2420 pr_warning("Could not create debugfs "
2421 "'available_events' entry\n");
2422
Li Zefan8728fe52010-05-24 16:22:49 +08002423 if (trace_define_common_fields())
2424 pr_warning("tracing: Failed to allocate common fields");
2425
Steven Rostedt77248222013-02-27 16:28:06 -05002426 ret = early_event_add_tracer(d_tracer, tr);
Steven Rostedtae63b312012-05-03 23:09:03 -04002427 if (ret)
2428 return ret;
Li Zefan020e5f82009-07-01 10:47:05 +08002429
Oleg Nesterov836d4812013-07-31 19:31:37 +02002430#ifdef CONFIG_MODULES
Steven Rostedt6d723732009-04-10 14:53:50 -04002431 ret = register_module_notifier(&trace_module_nb);
Ming Lei55379372009-05-18 23:04:46 +08002432 if (ret)
Steven Rostedt6d723732009-04-10 14:53:50 -04002433 pr_warning("Failed to register trace events module notifier\n");
Oleg Nesterov836d4812013-07-31 19:31:37 +02002434#endif
Steven Rostedtb77e38a2009-02-24 10:21:36 -05002435 return 0;
2436}
Steven Rostedtd1a29142013-02-27 20:23:57 -05002437early_initcall(event_trace_memsetup);
Ezequiel Garcia87819152012-09-12 11:47:57 -03002438core_initcall(event_trace_enable);
Steven Rostedtb77e38a2009-02-24 10:21:36 -05002439fs_initcall(event_trace_init);
Steven Rostedte6187002009-04-15 13:36:40 -04002440
2441#ifdef CONFIG_FTRACE_STARTUP_TEST
2442
2443static DEFINE_SPINLOCK(test_spinlock);
2444static DEFINE_SPINLOCK(test_spinlock_irq);
2445static DEFINE_MUTEX(test_mutex);
2446
2447static __init void test_work(struct work_struct *dummy)
2448{
2449 spin_lock(&test_spinlock);
2450 spin_lock_irq(&test_spinlock_irq);
2451 udelay(1);
2452 spin_unlock_irq(&test_spinlock_irq);
2453 spin_unlock(&test_spinlock);
2454
2455 mutex_lock(&test_mutex);
2456 msleep(1);
2457 mutex_unlock(&test_mutex);
2458}
2459
2460static __init int event_test_thread(void *unused)
2461{
2462 void *test_malloc;
2463
2464 test_malloc = kmalloc(1234, GFP_KERNEL);
2465 if (!test_malloc)
2466 pr_info("failed to kmalloc\n");
2467
2468 schedule_on_each_cpu(test_work);
2469
2470 kfree(test_malloc);
2471
2472 set_current_state(TASK_INTERRUPTIBLE);
2473 while (!kthread_should_stop())
2474 schedule();
2475
2476 return 0;
2477}
2478
2479/*
2480 * Do various things that may trigger events.
2481 */
2482static __init void event_test_stuff(void)
2483{
2484 struct task_struct *test_thread;
2485
2486 test_thread = kthread_run(event_test_thread, NULL, "test-events");
2487 msleep(1);
2488 kthread_stop(test_thread);
2489}
2490
2491/*
2492 * For every trace event defined, we will test each trace point separately,
2493 * and then by groups, and finally all trace points.
2494 */
Steven Rostedt9ea21c12009-04-16 12:15:44 -04002495static __init void event_trace_self_tests(void)
Steven Rostedte6187002009-04-15 13:36:40 -04002496{
Steven Rostedtae63b312012-05-03 23:09:03 -04002497 struct ftrace_subsystem_dir *dir;
2498 struct ftrace_event_file *file;
Steven Rostedte6187002009-04-15 13:36:40 -04002499 struct ftrace_event_call *call;
2500 struct event_subsystem *system;
Steven Rostedtae63b312012-05-03 23:09:03 -04002501 struct trace_array *tr;
Steven Rostedte6187002009-04-15 13:36:40 -04002502 int ret;
2503
Steven Rostedtae63b312012-05-03 23:09:03 -04002504 tr = top_trace_array();
2505
Steven Rostedte6187002009-04-15 13:36:40 -04002506 pr_info("Running tests on trace events:\n");
2507
Steven Rostedtae63b312012-05-03 23:09:03 -04002508 list_for_each_entry(file, &tr->events, list) {
2509
2510 call = file->event_call;
Steven Rostedte6187002009-04-15 13:36:40 -04002511
Steven Rostedt22392912010-04-21 12:27:06 -04002512 /* Only test those that have a probe */
2513 if (!call->class || !call->class->probe)
Steven Rostedte6187002009-04-15 13:36:40 -04002514 continue;
2515
Steven Rostedt1f5a6b42009-09-14 11:58:24 -04002516/*
2517 * Testing syscall events here is pretty useless, but
2518 * we still do it if configured. But this is time consuming.
2519 * What we really need is a user thread to perform the
2520 * syscalls as we test.
2521 */
2522#ifndef CONFIG_EVENT_TRACE_TEST_SYSCALLS
Steven Rostedt8f082012010-04-20 10:47:33 -04002523 if (call->class->system &&
2524 strcmp(call->class->system, "syscalls") == 0)
Steven Rostedt1f5a6b42009-09-14 11:58:24 -04002525 continue;
2526#endif
2527
Steven Rostedte6187002009-04-15 13:36:40 -04002528 pr_info("Testing event %s: ", call->name);
2529
2530 /*
2531 * If an event is already enabled, someone is using
2532 * it and the self test should not be on.
2533 */
Steven Rostedtae63b312012-05-03 23:09:03 -04002534 if (file->flags & FTRACE_EVENT_FL_ENABLED) {
Steven Rostedte6187002009-04-15 13:36:40 -04002535 pr_warning("Enabled event during self test!\n");
2536 WARN_ON_ONCE(1);
2537 continue;
2538 }
2539
Steven Rostedtae63b312012-05-03 23:09:03 -04002540 ftrace_event_enable_disable(file, 1);
Steven Rostedte6187002009-04-15 13:36:40 -04002541 event_test_stuff();
Steven Rostedtae63b312012-05-03 23:09:03 -04002542 ftrace_event_enable_disable(file, 0);
Steven Rostedte6187002009-04-15 13:36:40 -04002543
2544 pr_cont("OK\n");
2545 }
2546
2547 /* Now test at the sub system level */
2548
2549 pr_info("Running tests on trace event systems:\n");
2550
Steven Rostedtae63b312012-05-03 23:09:03 -04002551 list_for_each_entry(dir, &tr->systems, list) {
2552
2553 system = dir->subsystem;
Steven Rostedte6187002009-04-15 13:36:40 -04002554
2555 /* the ftrace system is special, skip it */
2556 if (strcmp(system->name, "ftrace") == 0)
2557 continue;
2558
2559 pr_info("Testing event system %s: ", system->name);
2560
Steven Rostedtae63b312012-05-03 23:09:03 -04002561 ret = __ftrace_set_clr_event(tr, NULL, system->name, NULL, 1);
Steven Rostedte6187002009-04-15 13:36:40 -04002562 if (WARN_ON_ONCE(ret)) {
2563 pr_warning("error enabling system %s\n",
2564 system->name);
2565 continue;
2566 }
2567
2568 event_test_stuff();
2569
Steven Rostedtae63b312012-05-03 23:09:03 -04002570 ret = __ftrace_set_clr_event(tr, NULL, system->name, NULL, 0);
Yuanhan Liu76bab1b2012-08-27 15:13:45 +08002571 if (WARN_ON_ONCE(ret)) {
Steven Rostedte6187002009-04-15 13:36:40 -04002572 pr_warning("error disabling system %s\n",
2573 system->name);
Yuanhan Liu76bab1b2012-08-27 15:13:45 +08002574 continue;
2575 }
Steven Rostedte6187002009-04-15 13:36:40 -04002576
2577 pr_cont("OK\n");
2578 }
2579
2580 /* Test with all events enabled */
2581
2582 pr_info("Running tests on all trace events:\n");
2583 pr_info("Testing all events: ");
2584
Steven Rostedtae63b312012-05-03 23:09:03 -04002585 ret = __ftrace_set_clr_event(tr, NULL, NULL, NULL, 1);
Steven Rostedte6187002009-04-15 13:36:40 -04002586 if (WARN_ON_ONCE(ret)) {
Steven Rostedte6187002009-04-15 13:36:40 -04002587 pr_warning("error enabling all events\n");
Steven Rostedt9ea21c12009-04-16 12:15:44 -04002588 return;
Steven Rostedte6187002009-04-15 13:36:40 -04002589 }
2590
2591 event_test_stuff();
2592
2593 /* reset sysname */
Steven Rostedtae63b312012-05-03 23:09:03 -04002594 ret = __ftrace_set_clr_event(tr, NULL, NULL, NULL, 0);
Steven Rostedte6187002009-04-15 13:36:40 -04002595 if (WARN_ON_ONCE(ret)) {
2596 pr_warning("error disabling all events\n");
Steven Rostedt9ea21c12009-04-16 12:15:44 -04002597 return;
Steven Rostedte6187002009-04-15 13:36:40 -04002598 }
2599
2600 pr_cont("OK\n");
Steven Rostedt9ea21c12009-04-16 12:15:44 -04002601}
2602
2603#ifdef CONFIG_FUNCTION_TRACER
2604
Tejun Heo245b2e72009-06-24 15:13:48 +09002605static DEFINE_PER_CPU(atomic_t, ftrace_test_event_disable);
Steven Rostedt9ea21c12009-04-16 12:15:44 -04002606
2607static void
Steven Rostedt2f5f6ad2011-08-08 16:57:47 -04002608function_test_events_call(unsigned long ip, unsigned long parent_ip,
Steven Rostedta1e2e312011-08-09 12:50:46 -04002609 struct ftrace_ops *op, struct pt_regs *pt_regs)
Steven Rostedt9ea21c12009-04-16 12:15:44 -04002610{
2611 struct ring_buffer_event *event;
Steven Rostedte77405a2009-09-02 14:17:06 -04002612 struct ring_buffer *buffer;
Steven Rostedt9ea21c12009-04-16 12:15:44 -04002613 struct ftrace_entry *entry;
2614 unsigned long flags;
2615 long disabled;
Steven Rostedt9ea21c12009-04-16 12:15:44 -04002616 int cpu;
2617 int pc;
2618
2619 pc = preempt_count();
Steven Rostedt5168ae52010-06-03 09:36:50 -04002620 preempt_disable_notrace();
Steven Rostedt9ea21c12009-04-16 12:15:44 -04002621 cpu = raw_smp_processor_id();
Tejun Heo245b2e72009-06-24 15:13:48 +09002622 disabled = atomic_inc_return(&per_cpu(ftrace_test_event_disable, cpu));
Steven Rostedt9ea21c12009-04-16 12:15:44 -04002623
2624 if (disabled != 1)
2625 goto out;
2626
2627 local_save_flags(flags);
2628
Steven Rostedte77405a2009-09-02 14:17:06 -04002629 event = trace_current_buffer_lock_reserve(&buffer,
2630 TRACE_FN, sizeof(*entry),
Steven Rostedt9ea21c12009-04-16 12:15:44 -04002631 flags, pc);
2632 if (!event)
2633 goto out;
2634 entry = ring_buffer_event_data(event);
2635 entry->ip = ip;
2636 entry->parent_ip = parent_ip;
2637
Steven Rostedt0d5c6e12012-11-01 20:54:21 -04002638 trace_buffer_unlock_commit(buffer, event, flags, pc);
Steven Rostedt9ea21c12009-04-16 12:15:44 -04002639
2640 out:
Tejun Heo245b2e72009-06-24 15:13:48 +09002641 atomic_dec(&per_cpu(ftrace_test_event_disable, cpu));
Steven Rostedt5168ae52010-06-03 09:36:50 -04002642 preempt_enable_notrace();
Steven Rostedt9ea21c12009-04-16 12:15:44 -04002643}
2644
2645static struct ftrace_ops trace_ops __initdata =
2646{
2647 .func = function_test_events_call,
Steven Rostedt47409742012-07-20 11:04:44 -04002648 .flags = FTRACE_OPS_FL_RECURSION_SAFE,
Steven Rostedt9ea21c12009-04-16 12:15:44 -04002649};
2650
2651static __init void event_trace_self_test_with_function(void)
2652{
Steven Rostedt17bb6152011-05-23 15:27:46 -04002653 int ret;
2654 ret = register_ftrace_function(&trace_ops);
2655 if (WARN_ON(ret < 0)) {
2656 pr_info("Failed to enable function tracer for event tests\n");
2657 return;
2658 }
Steven Rostedt9ea21c12009-04-16 12:15:44 -04002659 pr_info("Running tests again, along with the function tracer\n");
2660 event_trace_self_tests();
2661 unregister_ftrace_function(&trace_ops);
2662}
2663#else
2664static __init void event_trace_self_test_with_function(void)
2665{
2666}
2667#endif
2668
2669static __init int event_trace_self_tests_init(void)
2670{
Li Zefan020e5f82009-07-01 10:47:05 +08002671 if (!tracing_selftest_disabled) {
2672 event_trace_self_tests();
2673 event_trace_self_test_with_function();
2674 }
Steven Rostedte6187002009-04-15 13:36:40 -04002675
2676 return 0;
2677}
2678
Steven Rostedt28d20e22009-04-20 12:12:44 -04002679late_initcall(event_trace_self_tests_init);
Steven Rostedte6187002009-04-15 13:36:40 -04002680
2681#endif