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Commit | Line | Data |
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e5d355d1 AL |
1 | /* |
2 | * Wrappers around mutex/cond/thread functions | |
3 | * | |
4 | * Copyright Red Hat, Inc. 2009 | |
5 | * | |
6 | * Author: | |
7 | * Marcelo Tosatti <mtosatti@redhat.com> | |
8 | * | |
9 | * This work is licensed under the terms of the GNU GPL, version 2 or later. | |
10 | * See the COPYING file in the top-level directory. | |
11 | * | |
12 | */ | |
aafd7584 | 13 | #include "qemu/osdep.h" |
1de7afc9 | 14 | #include "qemu/thread.h" |
c7c4d063 | 15 | #include "qemu/atomic.h" |
ef57137f | 16 | #include "qemu/notify.h" |
f1aff7aa | 17 | #include "qemu-thread-common.h" |
ce9f0e5b | 18 | #include "qemu/tsan.h" |
7730f32c | 19 | #include "qemu/bitmap.h" |
e5d355d1 | 20 | |
3ada67a3 BS |
21 | #ifdef CONFIG_PTHREAD_SET_NAME_NP |
22 | #include <pthread_np.h> | |
23 | #endif | |
24 | ||
8f480de0 DDAG |
25 | static bool name_threads; |
26 | ||
27 | void qemu_thread_naming(bool enable) | |
28 | { | |
29 | name_threads = enable; | |
5c312079 | 30 | |
10f6b231 | 31 | #if !defined CONFIG_PTHREAD_SETNAME_NP_W_TID && \ |
3ada67a3 BS |
32 | !defined CONFIG_PTHREAD_SETNAME_NP_WO_TID && \ |
33 | !defined CONFIG_PTHREAD_SET_NAME_NP | |
5c312079 DDAG |
34 | /* This is a debugging option, not fatal */ |
35 | if (enable) { | |
36 | fprintf(stderr, "qemu: thread naming not supported on this host\n"); | |
37 | } | |
38 | #endif | |
8f480de0 DDAG |
39 | } |
40 | ||
e5d355d1 AL |
41 | static void error_exit(int err, const char *msg) |
42 | { | |
43 | fprintf(stderr, "qemu: %s: %s\n", msg, strerror(err)); | |
53380ac3 | 44 | abort(); |
e5d355d1 AL |
45 | } |
46 | ||
657ac98b LM |
47 | static inline clockid_t qemu_timedwait_clockid(void) |
48 | { | |
49 | #ifdef CONFIG_PTHREAD_CONDATTR_SETCLOCK | |
50 | return CLOCK_MONOTONIC; | |
51 | #else | |
52 | return CLOCK_REALTIME; | |
53 | #endif | |
54 | } | |
55 | ||
3dcc9c6e YK |
56 | static void compute_abs_deadline(struct timespec *ts, int ms) |
57 | { | |
657ac98b LM |
58 | clock_gettime(qemu_timedwait_clockid(), ts); |
59 | ts->tv_nsec += (ms % 1000) * 1000000; | |
60 | ts->tv_sec += ms / 1000; | |
3dcc9c6e YK |
61 | if (ts->tv_nsec >= 1000000000) { |
62 | ts->tv_sec++; | |
63 | ts->tv_nsec -= 1000000000; | |
64 | } | |
65 | } | |
66 | ||
e5d355d1 AL |
67 | void qemu_mutex_init(QemuMutex *mutex) |
68 | { | |
69 | int err; | |
70 | ||
24fa9049 | 71 | err = pthread_mutex_init(&mutex->lock, NULL); |
e5d355d1 AL |
72 | if (err) |
73 | error_exit(err, __func__); | |
f1aff7aa | 74 | qemu_mutex_post_init(mutex); |
e5d355d1 AL |
75 | } |
76 | ||
313b1d69 CC |
77 | void qemu_mutex_destroy(QemuMutex *mutex) |
78 | { | |
79 | int err; | |
80 | ||
c096358e FZ |
81 | assert(mutex->initialized); |
82 | mutex->initialized = false; | |
313b1d69 CC |
83 | err = pthread_mutex_destroy(&mutex->lock); |
84 | if (err) | |
85 | error_exit(err, __func__); | |
86 | } | |
87 | ||
6c27a0de | 88 | void qemu_mutex_lock_impl(QemuMutex *mutex, const char *file, const int line) |
e5d355d1 AL |
89 | { |
90 | int err; | |
91 | ||
c096358e | 92 | assert(mutex->initialized); |
f1aff7aa | 93 | qemu_mutex_pre_lock(mutex, file, line); |
e5d355d1 AL |
94 | err = pthread_mutex_lock(&mutex->lock); |
95 | if (err) | |
96 | error_exit(err, __func__); | |
f1aff7aa | 97 | qemu_mutex_post_lock(mutex, file, line); |
e5d355d1 AL |
98 | } |
99 | ||
6c27a0de | 100 | int qemu_mutex_trylock_impl(QemuMutex *mutex, const char *file, const int line) |
e5d355d1 | 101 | { |
31f5a726 JRZ |
102 | int err; |
103 | ||
c096358e | 104 | assert(mutex->initialized); |
31f5a726 JRZ |
105 | err = pthread_mutex_trylock(&mutex->lock); |
106 | if (err == 0) { | |
f1aff7aa | 107 | qemu_mutex_post_lock(mutex, file, line); |
31f5a726 JRZ |
108 | return 0; |
109 | } | |
110 | if (err != EBUSY) { | |
111 | error_exit(err, __func__); | |
112 | } | |
113 | return -EBUSY; | |
e5d355d1 AL |
114 | } |
115 | ||
6c27a0de | 116 | void qemu_mutex_unlock_impl(QemuMutex *mutex, const char *file, const int line) |
e5d355d1 AL |
117 | { |
118 | int err; | |
119 | ||
c096358e | 120 | assert(mutex->initialized); |
f1aff7aa | 121 | qemu_mutex_pre_unlock(mutex, file, line); |
e5d355d1 AL |
122 | err = pthread_mutex_unlock(&mutex->lock); |
123 | if (err) | |
124 | error_exit(err, __func__); | |
125 | } | |
126 | ||
feadec63 PB |
127 | void qemu_rec_mutex_init(QemuRecMutex *mutex) |
128 | { | |
129 | int err; | |
130 | pthread_mutexattr_t attr; | |
131 | ||
132 | pthread_mutexattr_init(&attr); | |
133 | pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE); | |
6c98635e | 134 | err = pthread_mutex_init(&mutex->m.lock, &attr); |
feadec63 PB |
135 | pthread_mutexattr_destroy(&attr); |
136 | if (err) { | |
137 | error_exit(err, __func__); | |
138 | } | |
6c98635e | 139 | mutex->m.initialized = true; |
feadec63 PB |
140 | } |
141 | ||
4b193bb7 RH |
142 | void qemu_rec_mutex_destroy(QemuRecMutex *mutex) |
143 | { | |
6c98635e | 144 | qemu_mutex_destroy(&mutex->m); |
4b193bb7 RH |
145 | } |
146 | ||
147 | void qemu_rec_mutex_lock_impl(QemuRecMutex *mutex, const char *file, int line) | |
148 | { | |
6c98635e | 149 | qemu_mutex_lock_impl(&mutex->m, file, line); |
4b193bb7 RH |
150 | } |
151 | ||
152 | int qemu_rec_mutex_trylock_impl(QemuRecMutex *mutex, const char *file, int line) | |
153 | { | |
6c98635e | 154 | return qemu_mutex_trylock_impl(&mutex->m, file, line); |
4b193bb7 RH |
155 | } |
156 | ||
9c75bae7 | 157 | void qemu_rec_mutex_unlock_impl(QemuRecMutex *mutex, const char *file, int line) |
4b193bb7 | 158 | { |
6c98635e | 159 | qemu_mutex_unlock_impl(&mutex->m, file, line); |
4b193bb7 RH |
160 | } |
161 | ||
e5d355d1 AL |
162 | void qemu_cond_init(QemuCond *cond) |
163 | { | |
657ac98b | 164 | pthread_condattr_t attr; |
e5d355d1 AL |
165 | int err; |
166 | ||
657ac98b LM |
167 | err = pthread_condattr_init(&attr); |
168 | if (err) { | |
169 | error_exit(err, __func__); | |
170 | } | |
171 | #ifdef CONFIG_PTHREAD_CONDATTR_SETCLOCK | |
172 | err = pthread_condattr_setclock(&attr, qemu_timedwait_clockid()); | |
173 | if (err) { | |
e5d355d1 | 174 | error_exit(err, __func__); |
657ac98b LM |
175 | } |
176 | #endif | |
177 | err = pthread_cond_init(&cond->cond, &attr); | |
178 | if (err) { | |
179 | error_exit(err, __func__); | |
180 | } | |
181 | err = pthread_condattr_destroy(&attr); | |
182 | if (err) { | |
183 | error_exit(err, __func__); | |
184 | } | |
c096358e | 185 | cond->initialized = true; |
e5d355d1 AL |
186 | } |
187 | ||
313b1d69 CC |
188 | void qemu_cond_destroy(QemuCond *cond) |
189 | { | |
190 | int err; | |
191 | ||
c096358e FZ |
192 | assert(cond->initialized); |
193 | cond->initialized = false; | |
313b1d69 CC |
194 | err = pthread_cond_destroy(&cond->cond); |
195 | if (err) | |
196 | error_exit(err, __func__); | |
197 | } | |
198 | ||
e5d355d1 AL |
199 | void qemu_cond_signal(QemuCond *cond) |
200 | { | |
201 | int err; | |
202 | ||
c096358e | 203 | assert(cond->initialized); |
e5d355d1 AL |
204 | err = pthread_cond_signal(&cond->cond); |
205 | if (err) | |
206 | error_exit(err, __func__); | |
207 | } | |
208 | ||
209 | void qemu_cond_broadcast(QemuCond *cond) | |
210 | { | |
211 | int err; | |
212 | ||
c096358e | 213 | assert(cond->initialized); |
e5d355d1 AL |
214 | err = pthread_cond_broadcast(&cond->cond); |
215 | if (err) | |
216 | error_exit(err, __func__); | |
217 | } | |
218 | ||
6c27a0de | 219 | void qemu_cond_wait_impl(QemuCond *cond, QemuMutex *mutex, const char *file, const int line) |
e5d355d1 AL |
220 | { |
221 | int err; | |
222 | ||
c096358e | 223 | assert(cond->initialized); |
f1aff7aa | 224 | qemu_mutex_pre_unlock(mutex, file, line); |
e5d355d1 | 225 | err = pthread_cond_wait(&cond->cond, &mutex->lock); |
f1aff7aa | 226 | qemu_mutex_post_lock(mutex, file, line); |
e5d355d1 AL |
227 | if (err) |
228 | error_exit(err, __func__); | |
229 | } | |
230 | ||
deb9c2ad | 231 | static bool TSA_NO_TSA |
a0d45db8 LM |
232 | qemu_cond_timedwait_ts(QemuCond *cond, QemuMutex *mutex, struct timespec *ts, |
233 | const char *file, const int line) | |
3dcc9c6e YK |
234 | { |
235 | int err; | |
3dcc9c6e YK |
236 | |
237 | assert(cond->initialized); | |
238 | trace_qemu_mutex_unlock(mutex, file, line); | |
a0d45db8 | 239 | err = pthread_cond_timedwait(&cond->cond, &mutex->lock, ts); |
3dcc9c6e YK |
240 | trace_qemu_mutex_locked(mutex, file, line); |
241 | if (err && err != ETIMEDOUT) { | |
242 | error_exit(err, __func__); | |
243 | } | |
244 | return err != ETIMEDOUT; | |
245 | } | |
246 | ||
a0d45db8 LM |
247 | bool qemu_cond_timedwait_impl(QemuCond *cond, QemuMutex *mutex, int ms, |
248 | const char *file, const int line) | |
249 | { | |
250 | struct timespec ts; | |
251 | ||
252 | compute_abs_deadline(&ts, ms); | |
253 | return qemu_cond_timedwait_ts(cond, mutex, &ts, file, line); | |
254 | } | |
255 | ||
38b14db3 PB |
256 | void qemu_sem_init(QemuSemaphore *sem, int init) |
257 | { | |
a0d45db8 LM |
258 | qemu_mutex_init(&sem->mutex); |
259 | qemu_cond_init(&sem->cond); | |
38b14db3 | 260 | |
c166cb72 PB |
261 | if (init < 0) { |
262 | error_exit(EINVAL, __func__); | |
263 | } | |
264 | sem->count = init; | |
38b14db3 PB |
265 | } |
266 | ||
267 | void qemu_sem_destroy(QemuSemaphore *sem) | |
268 | { | |
a0d45db8 LM |
269 | qemu_cond_destroy(&sem->cond); |
270 | qemu_mutex_destroy(&sem->mutex); | |
38b14db3 PB |
271 | } |
272 | ||
273 | void qemu_sem_post(QemuSemaphore *sem) | |
274 | { | |
a0d45db8 | 275 | qemu_mutex_lock(&sem->mutex); |
79761c66 | 276 | if (sem->count == UINT_MAX) { |
a0d45db8 | 277 | error_exit(EINVAL, __func__); |
c166cb72 | 278 | } else { |
79761c66 | 279 | sem->count++; |
a0d45db8 | 280 | qemu_cond_signal(&sem->cond); |
c166cb72 | 281 | } |
a0d45db8 | 282 | qemu_mutex_unlock(&sem->mutex); |
c166cb72 PB |
283 | } |
284 | ||
38b14db3 PB |
285 | int qemu_sem_timedwait(QemuSemaphore *sem, int ms) |
286 | { | |
a0d45db8 | 287 | bool rc = true; |
c166cb72 PB |
288 | struct timespec ts; |
289 | ||
c166cb72 | 290 | compute_abs_deadline(&ts, ms); |
a0d45db8 | 291 | qemu_mutex_lock(&sem->mutex); |
79761c66 | 292 | while (sem->count == 0) { |
8ab30264 PB |
293 | if (ms == 0) { |
294 | rc = false; | |
295 | } else { | |
296 | rc = qemu_cond_timedwait_ts(&sem->cond, &sem->mutex, &ts, | |
297 | __FILE__, __LINE__); | |
298 | } | |
a0d45db8 | 299 | if (!rc) { /* timeout */ |
c166cb72 PB |
300 | break; |
301 | } | |
c166cb72 | 302 | } |
a0d45db8 | 303 | if (rc) { |
79761c66 IT |
304 | --sem->count; |
305 | } | |
a0d45db8 LM |
306 | qemu_mutex_unlock(&sem->mutex); |
307 | return (rc ? 0 : -1); | |
38b14db3 PB |
308 | } |
309 | ||
310 | void qemu_sem_wait(QemuSemaphore *sem) | |
311 | { | |
a0d45db8 | 312 | qemu_mutex_lock(&sem->mutex); |
79761c66 | 313 | while (sem->count == 0) { |
a0d45db8 | 314 | qemu_cond_wait(&sem->cond, &sem->mutex); |
c166cb72 | 315 | } |
79761c66 | 316 | --sem->count; |
a0d45db8 | 317 | qemu_mutex_unlock(&sem->mutex); |
38b14db3 PB |
318 | } |
319 | ||
c7c4d063 | 320 | #ifdef __linux__ |
fbcc3e50 | 321 | #include "qemu/futex.h" |
c7c4d063 | 322 | #else |
fbcc3e50 | 323 | static inline void qemu_futex_wake(QemuEvent *ev, int n) |
c7c4d063 | 324 | { |
c096358e | 325 | assert(ev->initialized); |
158ef8cb | 326 | pthread_mutex_lock(&ev->lock); |
c7c4d063 PB |
327 | if (n == 1) { |
328 | pthread_cond_signal(&ev->cond); | |
329 | } else { | |
330 | pthread_cond_broadcast(&ev->cond); | |
331 | } | |
158ef8cb | 332 | pthread_mutex_unlock(&ev->lock); |
c7c4d063 PB |
333 | } |
334 | ||
fbcc3e50 | 335 | static inline void qemu_futex_wait(QemuEvent *ev, unsigned val) |
c7c4d063 | 336 | { |
c096358e | 337 | assert(ev->initialized); |
c7c4d063 PB |
338 | pthread_mutex_lock(&ev->lock); |
339 | if (ev->value == val) { | |
340 | pthread_cond_wait(&ev->cond, &ev->lock); | |
341 | } | |
342 | pthread_mutex_unlock(&ev->lock); | |
343 | } | |
344 | #endif | |
345 | ||
346 | /* Valid transitions: | |
347 | * - free->set, when setting the event | |
fbcc3e50 | 348 | * - busy->set, when setting the event, followed by qemu_futex_wake |
c7c4d063 PB |
349 | * - set->free, when resetting the event |
350 | * - free->busy, when waiting | |
351 | * | |
352 | * set->busy does not happen (it can be observed from the outside but | |
353 | * it really is set->free->busy). | |
354 | * | |
355 | * busy->free provably cannot happen; to enforce it, the set->free transition | |
356 | * is done with an OR, which becomes a no-op if the event has concurrently | |
357 | * transitioned to free or busy. | |
358 | */ | |
359 | ||
360 | #define EV_SET 0 | |
361 | #define EV_FREE 1 | |
362 | #define EV_BUSY -1 | |
363 | ||
364 | void qemu_event_init(QemuEvent *ev, bool init) | |
365 | { | |
366 | #ifndef __linux__ | |
367 | pthread_mutex_init(&ev->lock, NULL); | |
368 | pthread_cond_init(&ev->cond, NULL); | |
369 | #endif | |
370 | ||
371 | ev->value = (init ? EV_SET : EV_FREE); | |
c096358e | 372 | ev->initialized = true; |
c7c4d063 PB |
373 | } |
374 | ||
375 | void qemu_event_destroy(QemuEvent *ev) | |
376 | { | |
c096358e FZ |
377 | assert(ev->initialized); |
378 | ev->initialized = false; | |
c7c4d063 PB |
379 | #ifndef __linux__ |
380 | pthread_mutex_destroy(&ev->lock); | |
381 | pthread_cond_destroy(&ev->cond); | |
382 | #endif | |
383 | } | |
384 | ||
385 | void qemu_event_set(QemuEvent *ev) | |
386 | { | |
9586a132 PB |
387 | assert(ev->initialized); |
388 | ||
389 | /* | |
390 | * Pairs with both qemu_event_reset() and qemu_event_wait(). | |
391 | * | |
392 | * qemu_event_set has release semantics, but because it *loads* | |
374293ca PB |
393 | * ev->value we need a full memory barrier here. |
394 | */ | |
395 | smp_mb(); | |
d73415a3 | 396 | if (qatomic_read(&ev->value) != EV_SET) { |
9586a132 PB |
397 | int old = qatomic_xchg(&ev->value, EV_SET); |
398 | ||
399 | /* Pairs with memory barrier in kernel futex_wait system call. */ | |
400 | smp_mb__after_rmw(); | |
401 | if (old == EV_BUSY) { | |
c7c4d063 | 402 | /* There were waiters, wake them up. */ |
fbcc3e50 | 403 | qemu_futex_wake(ev, INT_MAX); |
c7c4d063 PB |
404 | } |
405 | } | |
406 | } | |
407 | ||
408 | void qemu_event_reset(QemuEvent *ev) | |
409 | { | |
c096358e | 410 | assert(ev->initialized); |
9586a132 PB |
411 | |
412 | /* | |
413 | * If there was a concurrent reset (or even reset+wait), | |
414 | * do nothing. Otherwise change EV_SET->EV_FREE. | |
415 | */ | |
416 | qatomic_or(&ev->value, EV_FREE); | |
417 | ||
418 | /* | |
419 | * Order reset before checking the condition in the caller. | |
420 | * Pairs with the first memory barrier in qemu_event_set(). | |
421 | */ | |
422 | smp_mb__after_rmw(); | |
c7c4d063 PB |
423 | } |
424 | ||
425 | void qemu_event_wait(QemuEvent *ev) | |
426 | { | |
427 | unsigned value; | |
428 | ||
c096358e | 429 | assert(ev->initialized); |
9586a132 PB |
430 | |
431 | /* | |
432 | * qemu_event_wait must synchronize with qemu_event_set even if it does | |
433 | * not go down the slow path, so this load-acquire is needed that | |
434 | * synchronizes with the first memory barrier in qemu_event_set(). | |
435 | * | |
436 | * If we do go down the slow path, there is no requirement at all: we | |
437 | * might miss a qemu_event_set() here but ultimately the memory barrier in | |
438 | * qemu_futex_wait() will ensure the check is done correctly. | |
439 | */ | |
440 | value = qatomic_load_acquire(&ev->value); | |
c7c4d063 PB |
441 | if (value != EV_SET) { |
442 | if (value == EV_FREE) { | |
443 | /* | |
9586a132 PB |
444 | * Leave the event reset and tell qemu_event_set that there are |
445 | * waiters. No need to retry, because there cannot be a concurrent | |
446 | * busy->free transition. After the CAS, the event will be either | |
447 | * set or busy. | |
448 | * | |
449 | * This cmpxchg doesn't have particular ordering requirements if it | |
450 | * succeeds (moving the store earlier can only cause qemu_event_set() | |
451 | * to issue _more_ wakeups), the failing case needs acquire semantics | |
452 | * like the load above. | |
c7c4d063 | 453 | */ |
d73415a3 | 454 | if (qatomic_cmpxchg(&ev->value, EV_FREE, EV_BUSY) == EV_SET) { |
c7c4d063 PB |
455 | return; |
456 | } | |
457 | } | |
9586a132 PB |
458 | |
459 | /* | |
460 | * This is the final check for a concurrent set, so it does need | |
461 | * a smp_mb() pairing with the second barrier of qemu_event_set(). | |
462 | * The barrier is inside the FUTEX_WAIT system call. | |
463 | */ | |
fbcc3e50 | 464 | qemu_futex_wait(ev, EV_BUSY); |
c7c4d063 PB |
465 | } |
466 | } | |
467 | ||
a458774a | 468 | static __thread NotifierList thread_exit; |
ef57137f | 469 | |
a458774a PM |
470 | /* |
471 | * Note that in this implementation you can register a thread-exit | |
472 | * notifier for the main thread, but it will never be called. | |
473 | * This is OK because main thread exit can only happen when the | |
474 | * entire process is exiting, and the API allows notifiers to not | |
475 | * be called on process exit. | |
476 | */ | |
ef57137f PB |
477 | void qemu_thread_atexit_add(Notifier *notifier) |
478 | { | |
a458774a | 479 | notifier_list_add(&thread_exit, notifier); |
ef57137f PB |
480 | } |
481 | ||
482 | void qemu_thread_atexit_remove(Notifier *notifier) | |
483 | { | |
ef57137f | 484 | notifier_remove(notifier); |
ef57137f PB |
485 | } |
486 | ||
a458774a | 487 | static void qemu_thread_atexit_notify(void *arg) |
ef57137f | 488 | { |
a458774a PM |
489 | /* |
490 | * Called when non-main thread exits (via qemu_thread_exit() | |
491 | * or by returning from its start routine.) | |
492 | */ | |
493 | notifier_list_notify(&thread_exit, NULL); | |
ef57137f PB |
494 | } |
495 | ||
68a93982 | 496 | typedef struct { |
497 | void *(*start_routine)(void *); | |
498 | void *arg; | |
499 | char *name; | |
500 | } QemuThreadArgs; | |
501 | ||
502 | static void *qemu_thread_start(void *args) | |
503 | { | |
504 | QemuThreadArgs *qemu_thread_args = args; | |
505 | void *(*start_routine)(void *) = qemu_thread_args->start_routine; | |
506 | void *arg = qemu_thread_args->arg; | |
a458774a | 507 | void *r; |
68a93982 | 508 | |
509 | /* Attempt to set the threads name; note that this is for debug, so | |
510 | * we're not going to fail if we can't set it. | |
511 | */ | |
d820fa5b | 512 | if (name_threads && qemu_thread_args->name) { |
479a5747 | 513 | # if defined(CONFIG_PTHREAD_SETNAME_NP_W_TID) |
d820fa5b | 514 | pthread_setname_np(pthread_self(), qemu_thread_args->name); |
479a5747 RB |
515 | # elif defined(CONFIG_PTHREAD_SETNAME_NP_WO_TID) |
516 | pthread_setname_np(qemu_thread_args->name); | |
3ada67a3 BS |
517 | # elif defined(CONFIG_PTHREAD_SET_NAME_NP) |
518 | pthread_set_name_np(pthread_self(), qemu_thread_args->name); | |
479a5747 | 519 | # endif |
d820fa5b | 520 | } |
ce9f0e5b | 521 | QEMU_TSAN_ANNOTATE_THREAD_NAME(qemu_thread_args->name); |
68a93982 | 522 | g_free(qemu_thread_args->name); |
523 | g_free(qemu_thread_args); | |
37daf1ba RH |
524 | |
525 | /* | |
526 | * GCC 11 with glibc 2.17 on PowerPC reports | |
527 | * | |
528 | * qemu-thread-posix.c:540:5: error: ‘__sigsetjmp’ accessing 656 bytes | |
529 | * in a region of size 528 [-Werror=stringop-overflow=] | |
530 | * 540 | pthread_cleanup_push(qemu_thread_atexit_notify, NULL); | |
531 | * | ^~~~~~~~~~~~~~~~~~~~ | |
532 | * | |
533 | * which is clearly nonsense. | |
534 | */ | |
535 | #pragma GCC diagnostic push | |
536 | #ifndef __clang__ | |
537 | #pragma GCC diagnostic ignored "-Wstringop-overflow" | |
538 | #endif | |
539 | ||
a458774a PM |
540 | pthread_cleanup_push(qemu_thread_atexit_notify, NULL); |
541 | r = start_routine(arg); | |
542 | pthread_cleanup_pop(1); | |
37daf1ba RH |
543 | |
544 | #pragma GCC diagnostic pop | |
545 | ||
a458774a | 546 | return r; |
5c312079 DDAG |
547 | } |
548 | ||
4900116e | 549 | void qemu_thread_create(QemuThread *thread, const char *name, |
e5d355d1 | 550 | void *(*start_routine)(void*), |
cf218714 | 551 | void *arg, int mode) |
e5d355d1 | 552 | { |
cf218714 | 553 | sigset_t set, oldset; |
e5d355d1 | 554 | int err; |
8763046b | 555 | pthread_attr_t attr; |
d820fa5b | 556 | QemuThreadArgs *qemu_thread_args; |
e5d355d1 | 557 | |
8763046b JK |
558 | err = pthread_attr_init(&attr); |
559 | if (err) { | |
560 | error_exit(err, __func__); | |
561 | } | |
55541c8a | 562 | |
68a93982 | 563 | if (mode == QEMU_THREAD_DETACHED) { |
564 | pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); | |
565 | } | |
566 | ||
cf218714 | 567 | /* Leave signal handling to the iothread. */ |
55541c8a | 568 | sigfillset(&set); |
21a43af0 RB |
569 | /* Blocking the signals can result in undefined behaviour. */ |
570 | sigdelset(&set, SIGSEGV); | |
571 | sigdelset(&set, SIGFPE); | |
572 | sigdelset(&set, SIGILL); | |
573 | /* TODO avoid SIGBUS loss on macOS */ | |
55541c8a | 574 | pthread_sigmask(SIG_SETMASK, &set, &oldset); |
55541c8a | 575 | |
d820fa5b PX |
576 | qemu_thread_args = g_new0(QemuThreadArgs, 1); |
577 | qemu_thread_args->name = g_strdup(name); | |
578 | qemu_thread_args->start_routine = start_routine; | |
579 | qemu_thread_args->arg = arg; | |
580 | ||
581 | err = pthread_create(&thread->thread, &attr, | |
582 | qemu_thread_start, qemu_thread_args); | |
4900116e | 583 | |
68a93982 | 584 | if (err) |
585 | error_exit(err, __func__); | |
586 | ||
55541c8a | 587 | pthread_sigmask(SIG_SETMASK, &oldset, NULL); |
8763046b JK |
588 | |
589 | pthread_attr_destroy(&attr); | |
e5d355d1 AL |
590 | } |
591 | ||
7730f32c DH |
592 | int qemu_thread_set_affinity(QemuThread *thread, unsigned long *host_cpus, |
593 | unsigned long nbits) | |
594 | { | |
595 | #if defined(CONFIG_PTHREAD_AFFINITY_NP) | |
596 | const size_t setsize = CPU_ALLOC_SIZE(nbits); | |
597 | unsigned long value; | |
598 | cpu_set_t *cpuset; | |
599 | int err; | |
600 | ||
601 | cpuset = CPU_ALLOC(nbits); | |
602 | g_assert(cpuset); | |
603 | ||
604 | CPU_ZERO_S(setsize, cpuset); | |
605 | value = find_first_bit(host_cpus, nbits); | |
606 | while (value < nbits) { | |
607 | CPU_SET_S(value, setsize, cpuset); | |
608 | value = find_next_bit(host_cpus, nbits, value + 1); | |
609 | } | |
610 | ||
611 | err = pthread_setaffinity_np(thread->thread, setsize, cpuset); | |
612 | CPU_FREE(cpuset); | |
613 | return err; | |
614 | #else | |
615 | return -ENOSYS; | |
616 | #endif | |
617 | } | |
618 | ||
619 | int qemu_thread_get_affinity(QemuThread *thread, unsigned long **host_cpus, | |
620 | unsigned long *nbits) | |
621 | { | |
622 | #if defined(CONFIG_PTHREAD_AFFINITY_NP) | |
623 | unsigned long tmpbits; | |
624 | cpu_set_t *cpuset; | |
625 | size_t setsize; | |
626 | int i, err; | |
627 | ||
628 | tmpbits = CPU_SETSIZE; | |
629 | while (true) { | |
630 | setsize = CPU_ALLOC_SIZE(tmpbits); | |
631 | cpuset = CPU_ALLOC(tmpbits); | |
632 | g_assert(cpuset); | |
633 | ||
634 | err = pthread_getaffinity_np(thread->thread, setsize, cpuset); | |
635 | if (err) { | |
636 | CPU_FREE(cpuset); | |
637 | if (err != -EINVAL) { | |
638 | return err; | |
639 | } | |
640 | tmpbits *= 2; | |
641 | } else { | |
642 | break; | |
643 | } | |
644 | } | |
645 | ||
646 | /* Convert the result into a proper bitmap. */ | |
647 | *nbits = tmpbits; | |
648 | *host_cpus = bitmap_new(tmpbits); | |
649 | for (i = 0; i < tmpbits; i++) { | |
650 | if (CPU_ISSET(i, cpuset)) { | |
651 | set_bit(i, *host_cpus); | |
652 | } | |
653 | } | |
654 | CPU_FREE(cpuset); | |
655 | return 0; | |
656 | #else | |
657 | return -ENOSYS; | |
658 | #endif | |
659 | } | |
660 | ||
b7680cb6 | 661 | void qemu_thread_get_self(QemuThread *thread) |
e5d355d1 AL |
662 | { |
663 | thread->thread = pthread_self(); | |
664 | } | |
665 | ||
2d797b65 | 666 | bool qemu_thread_is_self(QemuThread *thread) |
e5d355d1 | 667 | { |
b7680cb6 | 668 | return pthread_equal(pthread_self(), thread->thread); |
e5d355d1 AL |
669 | } |
670 | ||
313b1d69 CC |
671 | void qemu_thread_exit(void *retval) |
672 | { | |
673 | pthread_exit(retval); | |
674 | } | |
8763046b JK |
675 | |
676 | void *qemu_thread_join(QemuThread *thread) | |
677 | { | |
678 | int err; | |
679 | void *ret; | |
680 | ||
681 | err = pthread_join(thread->thread, &ret); | |
682 | if (err) { | |
683 | error_exit(err, __func__); | |
684 | } | |
685 | return ret; | |
686 | } |