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Diffstat (limited to 'lib/libthr/thread/thr_cond.c')
-rw-r--r--lib/libthr/thread/thr_cond.c127
1 files changed, 38 insertions, 89 deletions
diff --git a/lib/libthr/thread/thr_cond.c b/lib/libthr/thread/thr_cond.c
index e587a6d..eb50366 100644
--- a/lib/libthr/thread/thr_cond.c
+++ b/lib/libthr/thread/thr_cond.c
@@ -67,16 +67,12 @@ cond_init(pthread_cond_t *cond, const pthread_condattr_t *cond_attr)
int rval = 0;
if ((pcond = (pthread_cond_t)
- malloc(sizeof(struct pthread_cond))) == NULL) {
+ calloc(1, sizeof(struct pthread_cond))) == NULL) {
rval = ENOMEM;
} else {
/*
* Initialise the condition variable structure:
*/
- _thr_umutex_init(&pcond->c_lock);
- pcond->c_seqno = 0;
- pcond->c_waiters = 0;
- pcond->c_wakeups = 0;
if (cond_attr == NULL || *cond_attr == NULL) {
pcond->c_pshared = 0;
pcond->c_clockid = CLOCK_REALTIME;
@@ -84,6 +80,7 @@ cond_init(pthread_cond_t *cond, const pthread_condattr_t *cond_attr)
pcond->c_pshared = (*cond_attr)->c_pshared;
pcond->c_clockid = (*cond_attr)->c_clockid;
}
+ _thr_umutex_init(&pcond->c_lock);
*cond = pcond;
}
/* Return the completion status: */
@@ -118,31 +115,26 @@ _pthread_cond_init(pthread_cond_t *cond, const pthread_condattr_t *cond_attr)
int
_pthread_cond_destroy(pthread_cond_t *cond)
{
- struct pthread_cond *cv;
struct pthread *curthread = _get_curthread();
+ struct pthread_cond *cv;
int rval = 0;
if (*cond == NULL)
rval = EINVAL;
else {
+ cv = *cond;
+ THR_UMUTEX_LOCK(curthread, &cv->c_lock);
/* Lock the condition variable structure: */
- THR_LOCK_ACQUIRE(curthread, &(*cond)->c_lock);
- if ((*cond)->c_waiters + (*cond)->c_wakeups != 0) {
- THR_LOCK_RELEASE(curthread, &(*cond)->c_lock);
+ if (cv->c_kerncv.c_has_waiters) {
+ THR_UMUTEX_UNLOCK(curthread, &cv->c_lock);
return (EBUSY);
}
-
/*
* NULL the caller's pointer now that the condition
* variable has been destroyed:
*/
- cv = *cond;
*cond = NULL;
-
- /* Unlock the condition variable structure: */
- THR_LOCK_RELEASE(curthread, &cv->c_lock);
-
- /* Free the cond lock structure: */
+ THR_UMUTEX_UNLOCK(curthread, &cv->c_lock);
/*
* Free the memory allocated for the condition
@@ -159,7 +151,6 @@ struct cond_cancel_info
{
pthread_mutex_t *mutex;
pthread_cond_t *cond;
- long seqno;
int count;
};
@@ -168,21 +159,11 @@ cond_cancel_handler(void *arg)
{
struct pthread *curthread = _get_curthread();
struct cond_cancel_info *info = (struct cond_cancel_info *)arg;
- pthread_cond_t cv;
+ pthread_cond_t cv;
cv = *(info->cond);
- THR_LOCK_ACQUIRE(curthread, &cv->c_lock);
- if (cv->c_seqno != info->seqno && cv->c_wakeups != 0) {
- if (cv->c_waiters > 0) {
- cv->c_seqno++;
- _thr_umtx_wake(&cv->c_seqno, 1);
- } else
- cv->c_wakeups--;
- } else {
- cv->c_waiters--;
- }
- THR_LOCK_RELEASE(curthread, &cv->c_lock);
-
+ if ((cv->c_lock.m_owner & ~UMUTEX_CONTESTED) == TID(curthread))
+ THR_UMUTEX_UNLOCK(curthread, &cv->c_lock);
_mutex_cv_lock(info->mutex, info->count);
}
@@ -194,7 +175,6 @@ cond_wait_common(pthread_cond_t *cond, pthread_mutex_t *mutex,
struct timespec ts, ts2, *tsp;
struct cond_cancel_info info;
pthread_cond_t cv;
- long seq, oldseq;
int ret = 0;
/*
@@ -206,56 +186,34 @@ cond_wait_common(pthread_cond_t *cond, pthread_mutex_t *mutex,
return (ret);
cv = *cond;
- THR_LOCK_ACQUIRE(curthread, &cv->c_lock);
+ THR_UMUTEX_LOCK(curthread, &cv->c_lock);
ret = _mutex_cv_unlock(mutex, &info.count);
if (ret) {
- THR_LOCK_RELEASE(curthread, &cv->c_lock);
+ THR_UMUTEX_UNLOCK(curthread, &cv->c_lock);
return (ret);
}
- oldseq = seq = cv->c_seqno;
+
info.mutex = mutex;
info.cond = cond;
- info.seqno = oldseq;
-
- cv->c_waiters++;
- do {
- THR_LOCK_RELEASE(curthread, &cv->c_lock);
-
- if (abstime != NULL) {
- clock_gettime(cv->c_clockid, &ts);
- TIMESPEC_SUB(&ts2, abstime, &ts);
- tsp = &ts2;
- } else
- tsp = NULL;
-
- if (cancel) {
- THR_CLEANUP_PUSH(curthread, cond_cancel_handler, &info);
- _thr_cancel_enter(curthread);
- ret = _thr_umtx_wait(&cv->c_seqno, seq, tsp);
- _thr_cancel_leave(curthread);
- THR_CLEANUP_POP(curthread, 0);
- } else {
- ret = _thr_umtx_wait(&cv->c_seqno, seq, tsp);
- }
-
- THR_LOCK_ACQUIRE(curthread, &cv->c_lock);
- seq = cv->c_seqno;
- if (abstime != NULL && ret == ETIMEDOUT)
- break;
- /*
- * loop if we have never been told to wake up
- * or we lost a race.
- */
- } while (seq == oldseq || cv->c_wakeups == 0);
-
- if (seq != oldseq && cv->c_wakeups != 0) {
- cv->c_wakeups--;
- ret = 0;
+ if (abstime != NULL) {
+ clock_gettime(cv->c_clockid, &ts);
+ TIMESPEC_SUB(&ts2, abstime, &ts);
+ tsp = &ts2;
+ } else
+ tsp = NULL;
+
+ if (cancel) {
+ THR_CLEANUP_PUSH(curthread, cond_cancel_handler, &info);
+ _thr_cancel_enter_defer(curthread);
+ ret = _thr_ucond_wait(&cv->c_kerncv, &cv->c_lock, tsp, 1);
+ _thr_cancel_leave_defer(curthread, ret);
+ THR_CLEANUP_POP(curthread, 0);
} else {
- cv->c_waiters--;
+ ret = _thr_ucond_wait(&cv->c_kerncv, &cv->c_lock, tsp, 0);
}
- THR_LOCK_RELEASE(curthread, &cv->c_lock);
+ if (ret == EINTR)
+ ret = 0;
_mutex_cv_lock(mutex, info.count);
return (ret);
}
@@ -303,7 +261,7 @@ cond_signal_common(pthread_cond_t *cond, int broadcast)
{
struct pthread *curthread = _get_curthread();
pthread_cond_t cv;
- int ret = 0, oldwaiters;
+ int ret = 0;
/*
* If the condition variable is statically initialized, perform dynamic
@@ -314,23 +272,14 @@ cond_signal_common(pthread_cond_t *cond, int broadcast)
return (ret);
cv = *cond;
- /* Lock the condition variable structure. */
- THR_LOCK_ACQUIRE(curthread, &cv->c_lock);
- if (cv->c_waiters) {
- if (!broadcast) {
- cv->c_wakeups++;
- cv->c_waiters--;
- cv->c_seqno++;
- _thr_umtx_wake(&cv->c_seqno, 1);
- } else {
- oldwaiters = cv->c_waiters;
- cv->c_wakeups += cv->c_waiters;
- cv->c_waiters = 0;
- cv->c_seqno++;
- _thr_umtx_wake(&cv->c_seqno, oldwaiters);
- }
+ THR_UMUTEX_LOCK(curthread, &cv->c_lock);
+ if (cv->c_kerncv.c_has_waiters) {
+ if (!broadcast)
+ ret = _thr_ucond_signal(&cv->c_kerncv);
+ else
+ ret = _thr_ucond_broadcast(&cv->c_kerncv);
}
- THR_LOCK_RELEASE(curthread, &cv->c_lock);
+ THR_UMUTEX_UNLOCK(curthread, &cv->c_lock);
return (ret);
}
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