ABORT("sem_wait failed");
}
}
+# ifdef GC_ASSERTIONS
+ sem_getvalue(&GC_suspend_ack_sem, &i);
+ GC_ASSERT(0 == i);
+# endif
+}
+
+static int resend_lost_signals(int n_live_threads,
+ int (*suspend_restart_all)(void))
+{
+# define WAIT_UNIT 3000
+# define RETRY_INTERVAL 100000
+
+ if (n_live_threads > 0) {
+ unsigned long wait_usecs = 0; /* Total wait since retry. */
+ for (;;) {
+ int ack_count;
+
+ sem_getvalue(&GC_suspend_ack_sem, &ack_count);
+ if (ack_count == n_live_threads)
+ break;
+ if (wait_usecs > RETRY_INTERVAL) {
+ int newly_sent = suspend_restart_all();
+
+ GC_COND_LOG_PRINTF("Resent %d signals after timeout\n", newly_sent);
+ sem_getvalue(&GC_suspend_ack_sem, &ack_count);
+ if (newly_sent < n_live_threads - ack_count) {
+ WARN("Lost some threads while stoping or starting world?!\n", 0);
+ n_live_threads = ack_count + newly_sent;
+ }
+ wait_usecs = 0;
+ }
+
+# ifdef LINT2
+ /* Workaround "waiting while holding a lock" warning. */
+# undef WAIT_UNIT
+# define WAIT_UNIT 1
+ sched_yield();
+# elif defined(CPPCHECK) /* || _POSIX_C_SOURCE >= 199309L */
+ {
+ struct timespec ts;
+
+ ts.tv_sec = 0;
+ ts.tv_nsec = WAIT_UNIT * 1000;
+ (void)nanosleep(&ts, NULL);
+ }
+# else
+ usleep(WAIT_UNIT);
+# endif
+ wait_usecs += WAIT_UNIT;
+ }
+ }
+ return n_live_threads;
}
STATIC void GC_restart_handler(int sig)
# endif
pthread_t self = pthread_self();
-# ifdef DEBUG_THREADS
- GC_stopping_thread = self;
- GC_stopping_pid = getpid();
-# endif
for (i = 0; i < THREAD_TABLE_SZ; i++) {
for (p = GC_threads[i]; p != 0; p = p -> next) {
if (!THREAD_EQUAL(p -> id, self)) {
unsigned long num_sleeps = 0;
# ifdef DEBUG_THREADS
- GC_log_printf("pthread_stop_world: num_threads %d\n",
+ GC_log_printf("pthread_stop_world: num_threads=%d\n",
GC_nacl_num_gc_threads - 1);
# endif
GC_nacl_thread_parker = pthread_self();
GC_nacl_park_threads_now = 1;
-# ifdef DEBUG_THREADS
- GC_stopping_thread = GC_nacl_thread_parker;
- GC_stopping_pid = getpid();
-# endif
while (1) {
int num_threads_parked = 0;
# endif
GC_ASSERT(I_HOLD_LOCK());
# ifdef DEBUG_THREADS
- GC_log_printf("Stopping the world from %p\n", (void *)pthread_self());
+ GC_stopping_thread = pthread_self();
+ GC_stopping_pid = getpid();
+ GC_log_printf("Stopping the world from %p\n", (void *)GC_stopping_thread);
# endif
/* Make sure all free list construction has stopped before we start. */
/* Only concurrent reads are possible. */
AO_store_release(&GC_world_is_stopped, TRUE);
n_live_threads = GC_suspend_all();
-
- if (GC_retry_signals && n_live_threads > 0) {
- unsigned long wait_usecs = 0; /* Total wait since retry. */
-# define WAIT_UNIT 3000
-# define RETRY_INTERVAL 100000
- for (;;) {
- int ack_count;
-
- sem_getvalue(&GC_suspend_ack_sem, &ack_count);
- if (ack_count == n_live_threads) break;
- if (wait_usecs > RETRY_INTERVAL) {
- int newly_sent = GC_suspend_all();
-
- GC_COND_LOG_PRINTF("Resent %d signals after timeout\n", newly_sent);
- sem_getvalue(&GC_suspend_ack_sem, &ack_count);
- if (newly_sent < n_live_threads - ack_count) {
- WARN("Lost some threads during GC_stop_world?!\n",0);
- n_live_threads = ack_count + newly_sent;
- }
- wait_usecs = 0;
- }
-
-# ifdef LINT2
- /* Workaround "waiting while holding a lock" warning. */
-# undef WAIT_UNIT
-# define WAIT_UNIT 1
- sched_yield();
-# elif defined(CPPCHECK) /* || _POSIX_C_SOURCE >= 199309L */
- {
- struct timespec ts;
-
- ts.tv_sec = 0;
- ts.tv_nsec = WAIT_UNIT * 1000;
- (void)nanosleep(&ts, NULL);
- }
-# else
- usleep(WAIT_UNIT);
-# endif
- wait_usecs += WAIT_UNIT;
- }
- }
+ if (GC_retry_signals)
+ n_live_threads = resend_lost_signals(n_live_threads, GC_suspend_all);
suspend_restart_barrier(n_live_threads);
# endif
GC_nacl_num_gc_threads--;
pthread_mutex_unlock(&GC_nacl_thread_alloc_lock);
}
-#endif /* NACL */
-/* Caller holds allocation lock, and has held it continuously since */
-/* the world stopped. */
-GC_INNER void GC_start_world(void)
-{
-# ifndef NACL
- pthread_t self = pthread_self();
+#else /* !NACL */
+
+ /* Restart all threads that were suspended by the collector. */
+ /* Return the number of restart signals that were sent. */
+ STATIC int GC_restart_all(void)
+ {
+ int n_live_threads = 0;
int i;
+ pthread_t self = pthread_self();
GC_thread p;
# ifndef GC_OPENBSD_UTHREADS
- int n_live_threads = 0;
int result;
# endif
-# ifdef DEBUG_THREADS
- GC_log_printf("World starting\n");
-# endif
-
-# ifndef GC_OPENBSD_UTHREADS
- AO_store_release(&GC_world_is_stopped, FALSE);
- /* The updated value should now be visible to the */
- /* signal handler (note that pthread_kill is not on */
- /* the list of functions which synchronize memory). */
-# endif
for (i = 0; i < THREAD_TABLE_SZ; i++) {
- for (p = GC_threads[i]; p != 0; p = p -> next) {
+ for (p = GC_threads[i]; p != NULL; p = p -> next) {
if (!THREAD_EQUAL(p -> id, self)) {
- if ((p -> flags & FINISHED) != 0) continue;
- if (p -> thread_blocked) continue;
-# ifndef GC_OPENBSD_UTHREADS
-# ifdef GC_ENABLE_SUSPEND_THREAD
- if (p -> suspended_ext) continue;
-# endif
- n_live_threads++;
+ if ((p -> flags & FINISHED) != 0) continue;
+ if (p -> thread_blocked) continue;
+# ifndef GC_OPENBSD_UTHREADS
+# ifdef GC_ENABLE_SUSPEND_THREAD
+ if (p -> suspended_ext) continue;
# endif
-# ifdef DEBUG_THREADS
- GC_log_printf("Sending restart signal to %p\n", (void *)p->id);
-# endif
-
+ n_live_threads++;
+# endif
+# ifdef DEBUG_THREADS
+ GC_log_printf("Sending restart signal to %p\n", (void *)p->id);
+# endif
# ifdef GC_OPENBSD_UTHREADS
if (pthread_resume_np(p -> id) != 0)
ABORT("pthread_resume_np failed");
# else
result = RAISE_SIGNAL(p, GC_sig_thr_restart);
switch(result) {
- case ESRCH:
- /* Not really there anymore. Possible? */
- n_live_threads--;
- break;
- case 0:
- if (GC_on_thread_event)
- GC_on_thread_event(GC_EVENT_THREAD_UNSUSPENDED,
- (void *)(word)THREAD_SYSTEM_ID(p));
- break;
- default:
- ABORT_ARG1("pthread_kill failed at resume",
- ": errcode= %d", result);
+ case ESRCH:
+ /* Not really there anymore. Possible? */
+ n_live_threads--;
+ break;
+ case 0:
+ if (GC_on_thread_event)
+ GC_on_thread_event(GC_EVENT_THREAD_UNSUSPENDED,
+ (void *)(word)THREAD_SYSTEM_ID(p));
+ break;
+ default:
+ ABORT_ARG1("pthread_kill failed at resume",
+ ": errcode= %d", result);
}
# endif
}
}
}
-# ifdef GC_NETBSD_THREADS_WORKAROUND
- suspend_restart_barrier(n_live_threads);
+ return n_live_threads;
+ }
+#endif /* !NACL */
+
+/* Caller holds allocation lock, and has held it continuously since */
+/* the world stopped. */
+GC_INNER void GC_start_world(void)
+{
+# ifndef NACL
+ int n_live_threads;
+
+ GC_ASSERT(I_HOLD_LOCK());
+# ifdef DEBUG_THREADS
+ GC_log_printf("World starting\n");
# endif
-# if defined(GC_ASSERTIONS) && !defined(GC_OPENBSD_UTHREADS)
- {
- int ack_count;
- sem_getvalue(&GC_suspend_ack_sem, &ack_count);
- GC_ASSERT(0 == ack_count);
- }
+# ifndef GC_OPENBSD_UTHREADS
+ AO_store_release(&GC_world_is_stopped, FALSE);
+ /* The updated value should now be visible to the */
+ /* signal handler (note that pthread_kill is not on */
+ /* the list of functions which synchronize memory). */
+# endif
+ n_live_threads = GC_restart_all();
+# if !defined(GC_OPENBSD_UTHREADS) && defined(GC_NETBSD_THREADS_WORKAROUND)
+ suspend_restart_barrier(n_live_threads);
+# else
+ (void)n_live_threads;
# endif
# ifdef DEBUG_THREADS
GC_log_printf("World started\n");
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