Merge "Fix the POSIX timers fix."
diff --git a/libc/bionic/posix_timers.cpp b/libc/bionic/posix_timers.cpp
index e9190b2..59933ec 100644
--- a/libc/bionic/posix_timers.cpp
+++ b/libc/bionic/posix_timers.cpp
@@ -63,7 +63,6 @@
pthread_t callback_thread;
void (*callback)(sigval_t);
sigval_t callback_argument;
- volatile int exiting;
};
static __kernel_timer_t to_kernel_timer_id(timer_t timer) {
@@ -90,8 +89,7 @@
timer->callback(timer->callback_argument);
} else if (si.si_code == SI_TKILL) {
// This signal was sent because someone wants us to exit.
- timer->exiting = 1;
- __futex_wake(&timer->exiting, INT32_MAX);
+ free(timer);
return NULL;
}
}
@@ -99,46 +97,35 @@
static void __timer_thread_stop(PosixTimer* timer) {
pthread_kill(timer->callback_thread, TIMER_SIGNAL);
-
- // If this is being called from within the callback thread, do nothing else.
- if (pthread_self() != timer->callback_thread) {
- // We can't pthread_join because POSIX says "the threads created in response to a timer
- // expiration are created detached, or in an unspecified way if the thread attribute's
- // detachstate is PTHREAD_CREATE_JOINABLE".
- while (timer->exiting == 0) {
- __futex_wait(&timer->exiting, 0, NULL);
- }
- }
}
// http://pubs.opengroup.org/onlinepubs/9699919799/functions/timer_create.html
int timer_create(clockid_t clock_id, sigevent* evp, timer_t* timer_id) {
- PosixTimer* new_timer = reinterpret_cast<PosixTimer*>(malloc(sizeof(PosixTimer)));
- if (new_timer == NULL) {
+ PosixTimer* timer = reinterpret_cast<PosixTimer*>(malloc(sizeof(PosixTimer)));
+ if (timer == NULL) {
return -1;
}
- new_timer->sigev_notify = (evp == NULL) ? SIGEV_SIGNAL : evp->sigev_notify;
+ timer->sigev_notify = (evp == NULL) ? SIGEV_SIGNAL : evp->sigev_notify;
// If not a SIGEV_THREAD timer, the kernel can handle it without our help.
- if (new_timer->sigev_notify != SIGEV_THREAD) {
- if (__timer_create(clock_id, evp, &new_timer->kernel_timer_id) == -1) {
- free(new_timer);
+ if (timer->sigev_notify != SIGEV_THREAD) {
+ if (__timer_create(clock_id, evp, &timer->kernel_timer_id) == -1) {
+ free(timer);
return -1;
}
- *timer_id = new_timer;
+ *timer_id = timer;
return 0;
}
// Otherwise, this must be SIGEV_THREAD timer...
- new_timer->callback = evp->sigev_notify_function;
- new_timer->callback_argument = evp->sigev_value;
- new_timer->exiting = 0;
+ timer->callback = evp->sigev_notify_function;
+ timer->callback_argument = evp->sigev_value;
// Check arguments that the kernel doesn't care about but we do.
- if (new_timer->callback == NULL) {
- free(new_timer);
+ if (timer->callback == NULL) {
+ free(timer);
errno = EINVAL;
return -1;
}
@@ -159,12 +146,12 @@
kernel_sigset_t old_sigset;
pthread_sigmask(SIG_BLOCK, sigset.get(), old_sigset.get());
- int rc = pthread_create(&new_timer->callback_thread, &thread_attributes, __timer_thread_start, new_timer);
+ int rc = pthread_create(&timer->callback_thread, &thread_attributes, __timer_thread_start, timer);
pthread_sigmask(SIG_SETMASK, old_sigset.get(), NULL);
if (rc != 0) {
- free(new_timer);
+ free(timer);
errno = rc;
return -1;
}
@@ -172,20 +159,19 @@
sigevent se = *evp;
se.sigev_signo = TIMER_SIGNAL;
se.sigev_notify = SIGEV_THREAD_ID;
- se.sigev_notify_thread_id = __pthread_gettid(new_timer->callback_thread);
- if (__timer_create(clock_id, &se, &new_timer->kernel_timer_id) == -1) {
- __timer_thread_stop(new_timer);
- free(new_timer);
+ se.sigev_notify_thread_id = __pthread_gettid(timer->callback_thread);
+ if (__timer_create(clock_id, &se, &timer->kernel_timer_id) == -1) {
+ __timer_thread_stop(timer);
return -1;
}
// Give the thread a meaningful name.
// It can't do this itself because the kernel timer isn't created until after it's running.
char name[32];
- snprintf(name, sizeof(name), "POSIX interval timer %d", to_kernel_timer_id(new_timer));
- pthread_setname_np(new_timer->callback_thread, name);
+ snprintf(name, sizeof(name), "POSIX interval timer %d", to_kernel_timer_id(timer));
+ pthread_setname_np(timer->callback_thread, name);
- *timer_id = new_timer;
+ *timer_id = timer;
return 0;
}
@@ -197,14 +183,14 @@
}
PosixTimer* timer = reinterpret_cast<PosixTimer*>(id);
-
- // Make sure the timer's thread has exited before we free the timer data.
if (timer->sigev_notify == SIGEV_THREAD) {
+ // Stopping the timer's thread frees the timer data when it's safe.
__timer_thread_stop(timer);
+ } else {
+ // For timers without threads, we can just free right away.
+ free(timer);
}
- free(timer);
-
return 0;
}