blob: 7ad2262d2ecaa81d1bfd92754169bdc23b43c49d [file] [log] [blame]
Jens Axboe3d442232008-06-26 11:21:34 +02001/*
2 * Generic helpers for smp ipi calls
3 *
4 * (C) Jens Axboe <jens.axboe@oracle.com> 2008
Jens Axboe3d442232008-06-26 11:21:34 +02005 */
Jens Axboe3d442232008-06-26 11:21:34 +02006#include <linux/rcupdate.h>
Linus Torvalds59190f42008-07-15 14:02:33 -07007#include <linux/rculist.h>
Ingo Molnar0b13fda2009-02-25 16:52:11 +01008#include <linux/module.h>
9#include <linux/percpu.h>
10#include <linux/init.h>
Jens Axboe3d442232008-06-26 11:21:34 +020011#include <linux/smp.h>
Peter Zijlstra8969a5e2009-02-25 13:59:47 +010012#include <linux/cpu.h>
Jens Axboe3d442232008-06-26 11:21:34 +020013
14static DEFINE_PER_CPU(struct call_single_queue, call_single_queue);
Peter Zijlstra8969a5e2009-02-25 13:59:47 +010015
16static struct {
17 struct list_head queue;
18 spinlock_t lock;
Ingo Molnar0b13fda2009-02-25 16:52:11 +010019} call_function __cacheline_aligned_in_smp =
20 {
21 .queue = LIST_HEAD_INIT(call_function.queue),
22 .lock = __SPIN_LOCK_UNLOCKED(call_function.lock),
23 };
Jens Axboe3d442232008-06-26 11:21:34 +020024
25enum {
Peter Zijlstra6e275632009-02-25 13:59:48 +010026 CSD_FLAG_LOCK = 0x01,
Jens Axboe3d442232008-06-26 11:21:34 +020027};
28
29struct call_function_data {
Ingo Molnar0b13fda2009-02-25 16:52:11 +010030 struct call_single_data csd;
31 spinlock_t lock;
32 unsigned int refs;
33 cpumask_var_t cpumask;
Jens Axboe3d442232008-06-26 11:21:34 +020034};
35
36struct call_single_queue {
Ingo Molnar0b13fda2009-02-25 16:52:11 +010037 struct list_head list;
38 spinlock_t lock;
Jens Axboe3d442232008-06-26 11:21:34 +020039};
40
Peter Zijlstra8969a5e2009-02-25 13:59:47 +010041static DEFINE_PER_CPU(struct call_function_data, cfd_data) = {
Ingo Molnar0b13fda2009-02-25 16:52:11 +010042 .lock = __SPIN_LOCK_UNLOCKED(cfd_data.lock),
Peter Zijlstra8969a5e2009-02-25 13:59:47 +010043};
44
45static int
46hotplug_cfd(struct notifier_block *nfb, unsigned long action, void *hcpu)
47{
48 long cpu = (long)hcpu;
49 struct call_function_data *cfd = &per_cpu(cfd_data, cpu);
50
51 switch (action) {
52 case CPU_UP_PREPARE:
53 case CPU_UP_PREPARE_FROZEN:
54 if (!alloc_cpumask_var_node(&cfd->cpumask, GFP_KERNEL,
55 cpu_to_node(cpu)))
56 return NOTIFY_BAD;
57 break;
58
59#ifdef CONFIG_CPU_HOTPLUG
60 case CPU_UP_CANCELED:
61 case CPU_UP_CANCELED_FROZEN:
62
63 case CPU_DEAD:
64 case CPU_DEAD_FROZEN:
65 free_cpumask_var(cfd->cpumask);
66 break;
67#endif
68 };
69
70 return NOTIFY_OK;
71}
72
73static struct notifier_block __cpuinitdata hotplug_cfd_notifier = {
Ingo Molnar0b13fda2009-02-25 16:52:11 +010074 .notifier_call = hotplug_cfd,
Peter Zijlstra8969a5e2009-02-25 13:59:47 +010075};
76
Eduard - Gabriel Munteanu7babe8d2008-07-25 19:45:11 -070077static int __cpuinit init_call_single_data(void)
Jens Axboe3d442232008-06-26 11:21:34 +020078{
Peter Zijlstra8969a5e2009-02-25 13:59:47 +010079 void *cpu = (void *)(long)smp_processor_id();
Jens Axboe3d442232008-06-26 11:21:34 +020080 int i;
81
82 for_each_possible_cpu(i) {
83 struct call_single_queue *q = &per_cpu(call_single_queue, i);
84
85 spin_lock_init(&q->lock);
86 INIT_LIST_HEAD(&q->list);
87 }
Peter Zijlstra8969a5e2009-02-25 13:59:47 +010088
89 hotplug_cfd(&hotplug_cfd_notifier, CPU_UP_PREPARE, cpu);
90 register_cpu_notifier(&hotplug_cfd_notifier);
91
Eduard - Gabriel Munteanu7babe8d2008-07-25 19:45:11 -070092 return 0;
Jens Axboe3d442232008-06-26 11:21:34 +020093}
Eduard - Gabriel Munteanu7babe8d2008-07-25 19:45:11 -070094early_initcall(init_call_single_data);
Jens Axboe3d442232008-06-26 11:21:34 +020095
Peter Zijlstra8969a5e2009-02-25 13:59:47 +010096/*
Peter Zijlstra8969a5e2009-02-25 13:59:47 +010097 * csd_lock/csd_unlock used to serialize access to per-cpu csd resources
98 *
Ingo Molnar0b13fda2009-02-25 16:52:11 +010099 * For non-synchronous ipi calls the csd can still be in use by the
100 * previous function call. For multi-cpu calls its even more interesting
101 * as we'll have to ensure no other cpu is observing our csd.
Peter Zijlstra8969a5e2009-02-25 13:59:47 +0100102 */
Peter Zijlstra6e275632009-02-25 13:59:48 +0100103static void csd_lock_wait(struct call_single_data *data)
Peter Zijlstra8969a5e2009-02-25 13:59:47 +0100104{
105 while (data->flags & CSD_FLAG_LOCK)
106 cpu_relax();
Peter Zijlstra6e275632009-02-25 13:59:48 +0100107}
108
109static void csd_lock(struct call_single_data *data)
110{
111 csd_lock_wait(data);
Peter Zijlstra8969a5e2009-02-25 13:59:47 +0100112 data->flags = CSD_FLAG_LOCK;
113
114 /*
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100115 * prevent CPU from reordering the above assignment
116 * to ->flags with any subsequent assignments to other
117 * fields of the specified call_single_data structure:
Peter Zijlstra8969a5e2009-02-25 13:59:47 +0100118 */
Peter Zijlstra8969a5e2009-02-25 13:59:47 +0100119 smp_mb();
120}
121
122static void csd_unlock(struct call_single_data *data)
123{
124 WARN_ON(!(data->flags & CSD_FLAG_LOCK));
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100125
Peter Zijlstra8969a5e2009-02-25 13:59:47 +0100126 /*
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100127 * ensure we're all done before releasing data:
Peter Zijlstra8969a5e2009-02-25 13:59:47 +0100128 */
129 smp_mb();
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100130
Peter Zijlstra8969a5e2009-02-25 13:59:47 +0100131 data->flags &= ~CSD_FLAG_LOCK;
Jens Axboe3d442232008-06-26 11:21:34 +0200132}
133
134/*
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100135 * Insert a previously allocated call_single_data element
136 * for execution on the given CPU. data must already have
137 * ->func, ->info, and ->flags set.
Jens Axboe3d442232008-06-26 11:21:34 +0200138 */
Peter Zijlstra6e275632009-02-25 13:59:48 +0100139static
140void generic_exec_single(int cpu, struct call_single_data *data, int wait)
Jens Axboe3d442232008-06-26 11:21:34 +0200141{
142 struct call_single_queue *dst = &per_cpu(call_single_queue, cpu);
Jens Axboe3d442232008-06-26 11:21:34 +0200143 unsigned long flags;
Peter Zijlstra6e275632009-02-25 13:59:48 +0100144 int ipi;
Jens Axboe3d442232008-06-26 11:21:34 +0200145
146 spin_lock_irqsave(&dst->lock, flags);
147 ipi = list_empty(&dst->list);
148 list_add_tail(&data->list, &dst->list);
149 spin_unlock_irqrestore(&dst->lock, flags);
150
Suresh Siddha561920a02008-10-30 18:28:41 +0100151 /*
Nick Piggin15d0d3b2009-02-25 06:22:45 +0100152 * The list addition should be visible before sending the IPI
153 * handler locks the list to pull the entry off it because of
154 * normal cache coherency rules implied by spinlocks.
155 *
156 * If IPIs can go out of order to the cache coherency protocol
157 * in an architecture, sufficient synchronisation should be added
158 * to arch code to make it appear to obey cache coherency WRT
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100159 * locking and barrier primitives. Generic code isn't really
160 * equipped to do the right thing...
Suresh Siddha561920a02008-10-30 18:28:41 +0100161 */
Jens Axboe3d442232008-06-26 11:21:34 +0200162 if (ipi)
163 arch_send_call_function_single_ipi(cpu);
164
165 if (wait)
Peter Zijlstra6e275632009-02-25 13:59:48 +0100166 csd_lock_wait(data);
Jens Axboe3d442232008-06-26 11:21:34 +0200167}
168
169/*
170 * Invoked by arch to handle an IPI for call function. Must be called with
171 * interrupts disabled.
172 */
173void generic_smp_call_function_interrupt(void)
174{
175 struct call_function_data *data;
176 int cpu = get_cpu();
177
178 /*
Nick Piggin15d0d3b2009-02-25 06:22:45 +0100179 * Ensure entry is visible on call_function_queue after we have
180 * entered the IPI. See comment in smp_call_function_many.
181 * If we don't have this, then we may miss an entry on the list
182 * and never get another IPI to process it.
183 */
184 smp_mb();
185
186 /*
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100187 * It's ok to use list_for_each_rcu() here even though we may
188 * delete 'pos', since list_del_rcu() doesn't clear ->next
Jens Axboe3d442232008-06-26 11:21:34 +0200189 */
Peter Zijlstra8969a5e2009-02-25 13:59:47 +0100190 list_for_each_entry_rcu(data, &call_function.queue, csd.list) {
Jens Axboe3d442232008-06-26 11:21:34 +0200191 int refs;
192
Peter Zijlstra8969a5e2009-02-25 13:59:47 +0100193 spin_lock(&data->lock);
194 if (!cpumask_test_cpu(cpu, data->cpumask)) {
195 spin_unlock(&data->lock);
Jens Axboe3d442232008-06-26 11:21:34 +0200196 continue;
Peter Zijlstra8969a5e2009-02-25 13:59:47 +0100197 }
198 cpumask_clear_cpu(cpu, data->cpumask);
199 spin_unlock(&data->lock);
Jens Axboe3d442232008-06-26 11:21:34 +0200200
201 data->csd.func(data->csd.info);
202
203 spin_lock(&data->lock);
Jens Axboe3d442232008-06-26 11:21:34 +0200204 WARN_ON(data->refs == 0);
Peter Zijlstra8969a5e2009-02-25 13:59:47 +0100205 refs = --data->refs;
206 if (!refs) {
207 spin_lock(&call_function.lock);
208 list_del_rcu(&data->csd.list);
209 spin_unlock(&call_function.lock);
210 }
Jens Axboe3d442232008-06-26 11:21:34 +0200211 spin_unlock(&data->lock);
212
213 if (refs)
214 continue;
215
Peter Zijlstra8969a5e2009-02-25 13:59:47 +0100216 csd_unlock(&data->csd);
Jens Axboe3d442232008-06-26 11:21:34 +0200217 }
Jens Axboe3d442232008-06-26 11:21:34 +0200218
219 put_cpu();
220}
221
222/*
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100223 * Invoked by arch to handle an IPI for call function single. Must be
224 * called from the arch with interrupts disabled.
Jens Axboe3d442232008-06-26 11:21:34 +0200225 */
226void generic_smp_call_function_single_interrupt(void)
227{
228 struct call_single_queue *q = &__get_cpu_var(call_single_queue);
Nick Piggin15d0d3b2009-02-25 06:22:45 +0100229 unsigned int data_flags;
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100230 LIST_HEAD(list);
Jens Axboe3d442232008-06-26 11:21:34 +0200231
Nick Piggin15d0d3b2009-02-25 06:22:45 +0100232 spin_lock(&q->lock);
233 list_replace_init(&q->list, &list);
234 spin_unlock(&q->lock);
Jens Axboe3d442232008-06-26 11:21:34 +0200235
Nick Piggin15d0d3b2009-02-25 06:22:45 +0100236 while (!list_empty(&list)) {
237 struct call_single_data *data;
Jens Axboe3d442232008-06-26 11:21:34 +0200238
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100239 data = list_entry(list.next, struct call_single_data, list);
Nick Piggin15d0d3b2009-02-25 06:22:45 +0100240 list_del(&data->list);
Jens Axboe3d442232008-06-26 11:21:34 +0200241
Jens Axboe3d442232008-06-26 11:21:34 +0200242 /*
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100243 * 'data' can be invalid after this call if flags == 0
244 * (when called through generic_exec_single()),
245 * so save them away before making the call:
Jens Axboe3d442232008-06-26 11:21:34 +0200246 */
Nick Piggin15d0d3b2009-02-25 06:22:45 +0100247 data_flags = data->flags;
248
249 data->func(data->info);
250
Peter Zijlstra8969a5e2009-02-25 13:59:47 +0100251 /*
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100252 * Unlocked CSDs are valid through generic_exec_single():
Peter Zijlstra8969a5e2009-02-25 13:59:47 +0100253 */
254 if (data_flags & CSD_FLAG_LOCK)
255 csd_unlock(data);
Jens Axboe3d442232008-06-26 11:21:34 +0200256 }
257}
258
Steven Rostedtd7240b92009-01-29 10:08:01 -0500259static DEFINE_PER_CPU(struct call_single_data, csd_data);
260
Jens Axboe3d442232008-06-26 11:21:34 +0200261/*
262 * smp_call_function_single - Run a function on a specific CPU
263 * @func: The function to run. This must be fast and non-blocking.
264 * @info: An arbitrary pointer to pass to the function.
Jens Axboe3d442232008-06-26 11:21:34 +0200265 * @wait: If true, wait until function has completed on other CPUs.
266 *
267 * Returns 0 on success, else a negative status code. Note that @wait
268 * will be implicitly turned on in case of allocation failures, since
269 * we fall back to on-stack allocation.
270 */
271int smp_call_function_single(int cpu, void (*func) (void *info), void *info,
Jens Axboe8691e5a2008-06-06 11:18:06 +0200272 int wait)
Jens Axboe3d442232008-06-26 11:21:34 +0200273{
Peter Zijlstra8969a5e2009-02-25 13:59:47 +0100274 struct call_single_data d = {
275 .flags = 0,
276 };
Jens Axboe3d442232008-06-26 11:21:34 +0200277 unsigned long flags;
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100278 int this_cpu;
H. Peter Anvinf73be6d2008-08-25 17:07:14 -0700279 int err = 0;
Jens Axboe3d442232008-06-26 11:21:34 +0200280
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100281 /*
282 * prevent preemption and reschedule on another processor,
283 * as well as CPU removal
284 */
285 this_cpu = get_cpu();
286
Jens Axboe3d442232008-06-26 11:21:34 +0200287 /* Can deadlock when called with interrupts disabled */
288 WARN_ON(irqs_disabled());
289
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100290 if (cpu == this_cpu) {
Jens Axboe3d442232008-06-26 11:21:34 +0200291 local_irq_save(flags);
292 func(info);
293 local_irq_restore(flags);
H. Peter Anvinf73be6d2008-08-25 17:07:14 -0700294 } else {
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100295 if ((unsigned)cpu < nr_cpu_ids && cpu_online(cpu)) {
296 struct call_single_data *data = &d;
297
298 if (!wait)
299 data = &__get_cpu_var(csd_data);
300
301 csd_lock(data);
302
303 data->func = func;
304 data->info = info;
305 generic_exec_single(cpu, data, wait);
306 } else {
307 err = -ENXIO; /* CPU not online */
308 }
Jens Axboe3d442232008-06-26 11:21:34 +0200309 }
310
311 put_cpu();
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100312
H. Peter Anvinf73be6d2008-08-25 17:07:14 -0700313 return err;
Jens Axboe3d442232008-06-26 11:21:34 +0200314}
315EXPORT_SYMBOL(smp_call_function_single);
316
317/**
318 * __smp_call_function_single(): Run a function on another CPU
319 * @cpu: The CPU to run on.
320 * @data: Pre-allocated and setup data structure
321 *
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100322 * Like smp_call_function_single(), but allow caller to pass in a
323 * pre-allocated data structure. Useful for embedding @data inside
324 * other structures, for instance.
Jens Axboe3d442232008-06-26 11:21:34 +0200325 */
Peter Zijlstra6e275632009-02-25 13:59:48 +0100326void __smp_call_function_single(int cpu, struct call_single_data *data,
327 int wait)
Jens Axboe3d442232008-06-26 11:21:34 +0200328{
Peter Zijlstra6e275632009-02-25 13:59:48 +0100329 csd_lock(data);
Jens Axboe3d442232008-06-26 11:21:34 +0200330
Peter Zijlstra6e275632009-02-25 13:59:48 +0100331 /* Can deadlock when called with interrupts disabled */
332 WARN_ON(wait && irqs_disabled());
333
334 generic_exec_single(cpu, data, wait);
Jens Axboe3d442232008-06-26 11:21:34 +0200335}
336
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100337/* Deprecated: shim for archs using old arch_send_call_function_ipi API. */
338
Rusty Russellce47d972008-12-30 09:05:17 +1030339#ifndef arch_send_call_function_ipi_mask
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100340# define arch_send_call_function_ipi_mask(maskp) \
341 arch_send_call_function_ipi(*(maskp))
Rusty Russellce47d972008-12-30 09:05:17 +1030342#endif
343
Jens Axboe3d442232008-06-26 11:21:34 +0200344/**
Rusty Russell54b11e62008-12-30 09:05:16 +1030345 * smp_call_function_many(): Run a function on a set of other CPUs.
346 * @mask: The set of cpus to run on (only runs on online subset).
Jens Axboe3d442232008-06-26 11:21:34 +0200347 * @func: The function to run. This must be fast and non-blocking.
348 * @info: An arbitrary pointer to pass to the function.
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100349 * @wait: If true, wait (atomically) until function has completed
350 * on other CPUs.
Jens Axboe3d442232008-06-26 11:21:34 +0200351 *
Jens Axboe3d442232008-06-26 11:21:34 +0200352 * If @wait is true, then returns once @func has returned. Note that @wait
353 * will be implicitly turned on in case of allocation failures, since
354 * we fall back to on-stack allocation.
355 *
356 * You must not call this function with disabled interrupts or from a
357 * hardware interrupt handler or from a bottom half handler. Preemption
358 * must be disabled when calling this function.
359 */
Rusty Russell54b11e62008-12-30 09:05:16 +1030360void smp_call_function_many(const struct cpumask *mask,
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100361 void (*func)(void *), void *info, bool wait)
Jens Axboe3d442232008-06-26 11:21:34 +0200362{
Rusty Russell54b11e62008-12-30 09:05:16 +1030363 struct call_function_data *data;
Jens Axboe3d442232008-06-26 11:21:34 +0200364 unsigned long flags;
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100365 int cpu, next_cpu, this_cpu = smp_processor_id();
Jens Axboe3d442232008-06-26 11:21:34 +0200366
367 /* Can deadlock when called with interrupts disabled */
368 WARN_ON(irqs_disabled());
369
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100370 /* So, what's a CPU they want? Ignoring this one. */
Rusty Russell54b11e62008-12-30 09:05:16 +1030371 cpu = cpumask_first_and(mask, cpu_online_mask);
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100372 if (cpu == this_cpu)
Rusty Russell54b11e62008-12-30 09:05:16 +1030373 cpu = cpumask_next_and(cpu, mask, cpu_online_mask);
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100374
Rusty Russell54b11e62008-12-30 09:05:16 +1030375 /* No online cpus? We're done. */
376 if (cpu >= nr_cpu_ids)
377 return;
Jens Axboe3d442232008-06-26 11:21:34 +0200378
Rusty Russell54b11e62008-12-30 09:05:16 +1030379 /* Do we have another CPU which isn't us? */
380 next_cpu = cpumask_next_and(cpu, mask, cpu_online_mask);
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100381 if (next_cpu == this_cpu)
Rusty Russell54b11e62008-12-30 09:05:16 +1030382 next_cpu = cpumask_next_and(next_cpu, mask, cpu_online_mask);
383
384 /* Fastpath: do that cpu by itself. */
385 if (next_cpu >= nr_cpu_ids) {
386 smp_call_function_single(cpu, func, info, wait);
387 return;
Jens Axboe3d442232008-06-26 11:21:34 +0200388 }
389
Peter Zijlstra8969a5e2009-02-25 13:59:47 +0100390 data = &__get_cpu_var(cfd_data);
391 csd_lock(&data->csd);
Jens Axboe3d442232008-06-26 11:21:34 +0200392
Peter Zijlstra8969a5e2009-02-25 13:59:47 +0100393 spin_lock_irqsave(&data->lock, flags);
Jens Axboe3d442232008-06-26 11:21:34 +0200394 data->csd.func = func;
395 data->csd.info = info;
Peter Zijlstra8969a5e2009-02-25 13:59:47 +0100396 cpumask_and(data->cpumask, mask, cpu_online_mask);
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100397 cpumask_clear_cpu(this_cpu, data->cpumask);
Peter Zijlstra8969a5e2009-02-25 13:59:47 +0100398 data->refs = cpumask_weight(data->cpumask);
Jens Axboe3d442232008-06-26 11:21:34 +0200399
Peter Zijlstra8969a5e2009-02-25 13:59:47 +0100400 spin_lock(&call_function.lock);
401 /*
402 * Place entry at the _HEAD_ of the list, so that any cpu still
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100403 * observing the entry in generic_smp_call_function_interrupt()
404 * will not miss any other list entries:
Peter Zijlstra8969a5e2009-02-25 13:59:47 +0100405 */
406 list_add_rcu(&data->csd.list, &call_function.queue);
407 spin_unlock(&call_function.lock);
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100408
Peter Zijlstra8969a5e2009-02-25 13:59:47 +0100409 spin_unlock_irqrestore(&data->lock, flags);
Jens Axboe3d442232008-06-26 11:21:34 +0200410
Suresh Siddha561920a02008-10-30 18:28:41 +0100411 /*
412 * Make the list addition visible before sending the ipi.
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100413 * (IPIs must obey or appear to obey normal Linux cache
414 * coherency rules -- see comment in generic_exec_single).
Suresh Siddha561920a02008-10-30 18:28:41 +0100415 */
416 smp_mb();
417
Jens Axboe3d442232008-06-26 11:21:34 +0200418 /* Send a message to all CPUs in the map */
Peter Zijlstra8969a5e2009-02-25 13:59:47 +0100419 arch_send_call_function_ipi_mask(data->cpumask);
Jens Axboe3d442232008-06-26 11:21:34 +0200420
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100421 /* Optionally wait for the CPUs to complete */
Rusty Russell54b11e62008-12-30 09:05:16 +1030422 if (wait)
Peter Zijlstra6e275632009-02-25 13:59:48 +0100423 csd_lock_wait(&data->csd);
Jens Axboe3d442232008-06-26 11:21:34 +0200424}
Rusty Russell54b11e62008-12-30 09:05:16 +1030425EXPORT_SYMBOL(smp_call_function_many);
Jens Axboe3d442232008-06-26 11:21:34 +0200426
427/**
428 * smp_call_function(): Run a function on all other CPUs.
429 * @func: The function to run. This must be fast and non-blocking.
430 * @info: An arbitrary pointer to pass to the function.
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100431 * @wait: If true, wait (atomically) until function has completed
432 * on other CPUs.
Jens Axboe3d442232008-06-26 11:21:34 +0200433 *
Rusty Russell54b11e62008-12-30 09:05:16 +1030434 * Returns 0.
Jens Axboe3d442232008-06-26 11:21:34 +0200435 *
436 * If @wait is true, then returns once @func has returned; otherwise
437 * it returns just before the target cpu calls @func. In case of allocation
438 * failure, @wait will be implicitly turned on.
439 *
440 * You must not call this function with disabled interrupts or from a
441 * hardware interrupt handler or from a bottom half handler.
442 */
Jens Axboe8691e5a2008-06-06 11:18:06 +0200443int smp_call_function(void (*func)(void *), void *info, int wait)
Jens Axboe3d442232008-06-26 11:21:34 +0200444{
Jens Axboe3d442232008-06-26 11:21:34 +0200445 preempt_disable();
Rusty Russell54b11e62008-12-30 09:05:16 +1030446 smp_call_function_many(cpu_online_mask, func, info, wait);
Jens Axboe3d442232008-06-26 11:21:34 +0200447 preempt_enable();
Ingo Molnar0b13fda2009-02-25 16:52:11 +0100448
Rusty Russell54b11e62008-12-30 09:05:16 +1030449 return 0;
Jens Axboe3d442232008-06-26 11:21:34 +0200450}
451EXPORT_SYMBOL(smp_call_function);
452
453void ipi_call_lock(void)
454{
Peter Zijlstra8969a5e2009-02-25 13:59:47 +0100455 spin_lock(&call_function.lock);
Jens Axboe3d442232008-06-26 11:21:34 +0200456}
457
458void ipi_call_unlock(void)
459{
Peter Zijlstra8969a5e2009-02-25 13:59:47 +0100460 spin_unlock(&call_function.lock);
Jens Axboe3d442232008-06-26 11:21:34 +0200461}
462
463void ipi_call_lock_irq(void)
464{
Peter Zijlstra8969a5e2009-02-25 13:59:47 +0100465 spin_lock_irq(&call_function.lock);
Jens Axboe3d442232008-06-26 11:21:34 +0200466}
467
468void ipi_call_unlock_irq(void)
469{
Peter Zijlstra8969a5e2009-02-25 13:59:47 +0100470 spin_unlock_irq(&call_function.lock);
Jens Axboe3d442232008-06-26 11:21:34 +0200471}