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authorUlrich Drepper <drepper@redhat.com>2000-07-26 02:18:41 +0000
committerUlrich Drepper <drepper@redhat.com>2000-07-26 02:18:41 +0000
commit9ec9e34ee301ccfa4216939639be5498831f9d37 (patch)
treee61a7957abfbeb4816cb6dc545c116b8e18159b5 /linuxthreads
parenta956d04575bbd053a1ff61a05a5526867633d0d0 (diff)
downloadglibc-9ec9e34ee301ccfa4216939639be5498831f9d37.tar.gz
Update.
* internals.h (strict __pthread_descr_struct): Add p_sem_avail. * semaphore.c: Handle spurious wakeups. * sysdeps/pthread/pthread.h: Add back PTHREAD_MUTX_FAST_NP as an alias for PTHREAD_MUTEX_ADAPTIVE_NP for source code compatibility. * pthread.c (__pthread_set_own_extricate): Use THREAD_GETMEM. (__pthread_wait_for_restart): Likewise. * condvar.c (pthread_cond_wait): Also check whether thread is cancelable before aborting loop. (pthread_cond_timedwait): Likewise.
Diffstat (limited to 'linuxthreads')
-rw-r--r--linuxthreads/ChangeLog13
-rw-r--r--linuxthreads/condvar.c6
-rw-r--r--linuxthreads/internals.h1
-rw-r--r--linuxthreads/pthread.c8
-rw-r--r--linuxthreads/semaphore.c62
-rw-r--r--linuxthreads/sysdeps/pthread/pthread.h4
6 files changed, 74 insertions, 20 deletions
diff --git a/linuxthreads/ChangeLog b/linuxthreads/ChangeLog
index 880de6a0b9..b0ae0eea25 100644
--- a/linuxthreads/ChangeLog
+++ b/linuxthreads/ChangeLog
@@ -1,5 +1,18 @@
2000-07-25 Ulrich Drepper <drepper@redhat.com>
+ * internals.h (strict __pthread_descr_struct): Add p_sem_avail.
+ * semaphore.c: Handle spurious wakeups.
+
+ * sysdeps/pthread/pthread.h: Add back PTHREAD_MUTX_FAST_NP as an alias
+ for PTHREAD_MUTEX_ADAPTIVE_NP for source code compatibility.
+
+ * pthread.c (__pthread_set_own_extricate): Use THREAD_GETMEM.
+ (__pthread_wait_for_restart): Likewise.
+
+ * condvar.c (pthread_cond_wait): Also check whether thread is
+ cancelable before aborting loop.
+ (pthread_cond_timedwait): Likewise.
+
* signals.c (pthread_sighandler): Remove special code to restrore
%gs on x86.
(pthread_sighandler_t): Likewise.
diff --git a/linuxthreads/condvar.c b/linuxthreads/condvar.c
index ae1cef1ea9..f9c46a3316 100644
--- a/linuxthreads/condvar.c
+++ b/linuxthreads/condvar.c
@@ -103,7 +103,8 @@ int pthread_cond_wait(pthread_cond_t *cond, pthread_mutex_t *mutex)
{
suspend(self);
if (THREAD_GETMEM(self, p_condvar_avail) == 0
- && THREAD_GETMEM(self, p_woken_by_cancel) == 0)
+ && (THREAD_GETMEM(self, p_woken_by_cancel) == 0
+ || THREAD_GETMEM(self, p_cancelstate) != PTHREAD_CANCEL_ENABLE))
{
/* Count resumes that don't belong to us. */
spurious_wakeup_count++;
@@ -196,7 +197,8 @@ pthread_cond_timedwait_relative(pthread_cond_t *cond,
}
if (THREAD_GETMEM(self, p_condvar_avail) == 0
- && THREAD_GETMEM(self, p_woken_by_cancel) == 0)
+ && (THREAD_GETMEM(self, p_woken_by_cancel) == 0
+ || THREAD_GETMEM(self, p_cancelstate) != PTHREAD_CANCEL_ENABLE))
{
/* Count resumes that don't belong to us. */
spurious_wakeup_count++;
diff --git a/linuxthreads/internals.h b/linuxthreads/internals.h
index 2ed49295ee..93ec93620c 100644
--- a/linuxthreads/internals.h
+++ b/linuxthreads/internals.h
@@ -168,6 +168,7 @@ struct _pthread_descr_struct {
called on thread */
char p_woken_by_cancel; /* cancellation performed wakeup */
char p_condvar_avail; /* flag if conditional variable became avail */
+ char p_sem_avail; /* flag if semaphore became available */
pthread_extricate_if *p_extricate; /* See above */
pthread_readlock_info *p_readlock_list; /* List of readlock info structs */
pthread_readlock_info *p_readlock_free; /* Free list of structs */
diff --git a/linuxthreads/pthread.c b/linuxthreads/pthread.c
index 3a669c8dec..7195b2dedc 100644
--- a/linuxthreads/pthread.c
+++ b/linuxthreads/pthread.c
@@ -868,9 +868,9 @@ weak_alias (__pthread_getconcurrency, pthread_getconcurrency)
void __pthread_set_own_extricate_if(pthread_descr self, pthread_extricate_if *peif)
{
- __pthread_lock(self->p_lock, self);
+ __pthread_lock(THREAD_GETMEM(self, p_lock), self);
THREAD_SETMEM(self, p_extricate, peif);
- __pthread_unlock(self->p_lock);
+ __pthread_unlock(THREAD_GETMEM (self, p_lock));
}
/* Primitives for controlling thread execution */
@@ -881,10 +881,10 @@ void __pthread_wait_for_restart_signal(pthread_descr self)
sigprocmask(SIG_SETMASK, NULL, &mask); /* Get current signal mask */
sigdelset(&mask, __pthread_sig_restart); /* Unblock the restart signal */
+ THREAD_SETMEM(self, p_signal, 0);
do {
- self->p_signal = 0;
sigsuspend(&mask); /* Wait for signal */
- } while (self->p_signal !=__pthread_sig_restart );
+ } while (THREAD_GETMEM(self, p_signal) !=__pthread_sig_restart);
}
#if !__ASSUME_REALTIME_SIGNALS
diff --git a/linuxthreads/semaphore.c b/linuxthreads/semaphore.c
index a772ea5091..e5afce43eb 100644
--- a/linuxthreads/semaphore.c
+++ b/linuxthreads/semaphore.c
@@ -60,6 +60,7 @@ int __new_sem_wait(sem_t * sem)
volatile pthread_descr self = thread_self();
pthread_extricate_if extr;
int already_canceled = 0;
+ int spurious_wakeup_count;
/* Set up extrication interface */
extr.pu_object = sem;
@@ -72,6 +73,7 @@ int __new_sem_wait(sem_t * sem)
return 0;
}
/* Register extrication interface */
+ THREAD_SETMEM(self, p_sem_avail, 0);
__pthread_set_own_extricate_if(self, &extr);
/* Enqueue only if not already cancelled. */
if (!(THREAD_GETMEM(self, p_canceled)
@@ -87,7 +89,20 @@ int __new_sem_wait(sem_t * sem)
}
/* Wait for sem_post or cancellation, or fall through if already canceled */
- suspend(self);
+ spurious_wakeup_count = 0;
+ while (1)
+ {
+ suspend(self);
+ if (THREAD_GETMEM(self, p_sem_avail) == 0
+ && (THREAD_GETMEM(self, p_woken_by_cancel) == 0
+ || THREAD_GETMEM(self, p_cancelstate) != PTHREAD_CANCEL_ENABLE))
+ {
+ /* Count resumes that don't belong to us. */
+ spurious_wakeup_count++;
+ continue;
+ }
+ break;
+ }
__pthread_set_own_extricate_if(self, 0);
/* Terminate only if the wakeup came from cancellation. */
@@ -138,6 +153,8 @@ int __new_sem_post(sem_t * sem)
} else {
th = dequeue(&sem->__sem_waiting);
__pthread_unlock((struct _pthread_fastlock *) &sem->__sem_lock);
+ th->p_sem_avail = 1;
+ WRITE_MEMORY_BARRIER();
restart(th);
}
} else {
@@ -195,6 +212,7 @@ int sem_timedwait(sem_t *sem, const struct timespec *abstime)
pthread_descr self = thread_self();
pthread_extricate_if extr;
int already_canceled = 0;
+ int spurious_wakeup_count;
__pthread_lock((struct _pthread_fastlock *) &sem->__sem_lock, self);
if (sem->__sem_value > 0) {
@@ -215,6 +233,7 @@ int sem_timedwait(sem_t *sem, const struct timespec *abstime)
extr.pu_extricate_func = new_sem_extricate_func;
/* Register extrication interface */
+ THREAD_SETMEM(self, p_sem_avail, 0);
__pthread_set_own_extricate_if(self, &extr);
/* Enqueue only if not already cancelled. */
if (!(THREAD_GETMEM(self, p_canceled)
@@ -229,24 +248,39 @@ int sem_timedwait(sem_t *sem, const struct timespec *abstime)
pthread_exit(PTHREAD_CANCELED);
}
- if (timedsuspend(self, abstime) == 0) {
- int was_on_queue;
+ spurious_wakeup_count = 0;
+ while (1)
+ {
+ if (timedsuspend(self, abstime) == 0) {
+ int was_on_queue;
+
+ /* __pthread_lock will queue back any spurious restarts that
+ may happen to it. */
- /* __pthread_lock will queue back any spurious restarts that
- may happen to it. */
+ __pthread_lock((struct _pthread_fastlock *)&sem->__sem_lock, self);
+ was_on_queue = remove_from_queue(&sem->__sem_waiting, self);
+ __pthread_unlock((struct _pthread_fastlock *)&sem->__sem_lock);
- __pthread_lock((struct _pthread_fastlock *)&sem->__sem_lock, self);
- was_on_queue = remove_from_queue(&sem->__sem_waiting, self);
- __pthread_unlock((struct _pthread_fastlock *)&sem->__sem_lock);
+ if (was_on_queue) {
+ __pthread_set_own_extricate_if(self, 0);
+ return ETIMEDOUT;
+ }
- if (was_on_queue) {
- __pthread_set_own_extricate_if(self, 0);
- return ETIMEDOUT;
+ /* Eat the outstanding restart() from the signaller */
+ suspend(self);
+ }
+
+ if (THREAD_GETMEM(self, p_sem_avail) == 0
+ && (THREAD_GETMEM(self, p_woken_by_cancel) == 0
+ || THREAD_GETMEM(self, p_cancelstate) != PTHREAD_CANCEL_ENABLE))
+ {
+ /* Count resumes that don't belong to us. */
+ spurious_wakeup_count++;
+ continue;
+ }
+ break;
}
- /* Eat the outstanding restart() from the signaller */
- suspend(self);
- }
__pthread_set_own_extricate_if(self, 0);
/* Terminate only if the wakeup came from cancellation. */
diff --git a/linuxthreads/sysdeps/pthread/pthread.h b/linuxthreads/sysdeps/pthread/pthread.h
index dd27ae0678..b017007f80 100644
--- a/linuxthreads/sysdeps/pthread/pthread.h
+++ b/linuxthreads/sysdeps/pthread/pthread.h
@@ -88,6 +88,10 @@ enum
PTHREAD_MUTEX_ERRORCHECK = PTHREAD_MUTEX_ERRORCHECK_NP,
PTHREAD_MUTEX_DEFAULT = PTHREAD_MUTEX_NORMAL
#endif
+#ifdef __USE_GNU
+ /* For compatibility. */
+ , PTHREAD_MUTEX_FAST_NP = PTHREAD_MUTEX_ADAPTIVE_NP
+#endif
};
enum