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Move checking for c_has_waiters into low level _thr_ucond_signal and

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_thr_ucond_broadcast, clear condition variable pointer in cancellation
info after returing from _thr_ucond_wait, since kernel has already
dropped the internal lock, so we don't need to unlock it in cancellation
handler again.
This commit is contained in:
David Xu 2006-12-12 03:08:49 +00:00
parent 48939a31e5
commit 347126a2e2
2 changed files with 12 additions and 16 deletions
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14
lib/libthr/thread/thr_cond.c
View File

@ -124,13 +124,6 @@ _pthread_cond_destroy(pthread_cond_t *cond)
else {
cv = *cond;
THR_UMUTEX_LOCK(curthread, &cv->c_lock);
#if 0
/* Lock the condition variable structure: */
if (cv->c_kerncv.c_has_waiters) {
THR_UMUTEX_UNLOCK(curthread, &cv->c_lock);
return (EBUSY);
}
#endif
/*
* NULL the caller's pointer now that the condition
* variable has been destroyed:
@ -143,7 +136,6 @@ _pthread_cond_destroy(pthread_cond_t *cond)
* variable structure:
*/
free(cv);
}
/* Return the completion status: */
return (rval);
@ -163,9 +155,10 @@ cond_cancel_handler(void *arg)
struct cond_cancel_info *info = (struct cond_cancel_info *)arg;
pthread_cond_t cv;
if (info->cond != NULL) {
cv = *(info->cond);
if ((cv->c_lock.m_owner & ~UMUTEX_CONTESTED) == TID(curthread))
THR_UMUTEX_UNLOCK(curthread, &cv->c_lock);
}
_mutex_cv_lock(info->mutex, info->count);
}
@ -209,6 +202,7 @@ cond_wait_common(pthread_cond_t *cond, pthread_mutex_t *mutex,
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);
info.cond = NULL;
_thr_cancel_leave_defer(curthread, ret);
THR_CLEANUP_POP(curthread, 0);
} else {
@ -275,12 +269,10 @@ cond_signal_common(pthread_cond_t *cond, int broadcast)
cv = *cond;
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_UMUTEX_UNLOCK(curthread, &cv->c_lock);
return (ret);
}

4
lib/libthr/thread/thr_umtx.c
View File

@ -131,6 +131,8 @@ _thr_ucond_wait(struct ucond *cv, struct umutex *m,
int
_thr_ucond_signal(struct ucond *cv)
{
if (!cv->c_has_waiters)
return (0);
if (_umtx_op(cv, UMTX_OP_CV_SIGNAL, 0, NULL, NULL) == 0)
return (0);
return (errno);
@ -139,6 +141,8 @@ _thr_ucond_signal(struct ucond *cv)
int
_thr_ucond_broadcast(struct ucond *cv)
{
if (!cv->c_has_waiters)
return (0);
if (_umtx_op(cv, UMTX_OP_CV_BROADCAST, 0, NULL, NULL) == 0)
return (0);
return (errno);