diff options
Diffstat (limited to 'src/thread/pthread_cond_timedwait.c')
-rw-r--r-- | src/thread/pthread_cond_timedwait.c | 21 |
1 files changed, 19 insertions, 2 deletions
diff --git a/src/thread/pthread_cond_timedwait.c b/src/thread/pthread_cond_timedwait.c index c71edc95..9616dd85 100644 --- a/src/thread/pthread_cond_timedwait.c +++ b/src/thread/pthread_cond_timedwait.c @@ -5,10 +5,25 @@ struct cm { pthread_mutex_t *m; }; +static void unwait(pthread_cond_t *c, pthread_mutex_t *m) +{ + int w; + + /* Cannot leave waiting status if there are any live broadcasters + * which might be inspecting/using the mutex. */ + while ((w=c->_c_bcast)) __wait(&c->_c_bcast, &c->_c_leavers, w, 0); + + /* If the waiter count is zero, it must be the case that the + * caller's count has been moved to the mutex due to bcast. */ + do w = c->_c_waiters; + while (w && a_cas(&c->_c_waiters, w, w-1)!=w); + if (!w) a_dec(&m->_m_waiters); +} + static void cleanup(void *p) { struct cm *cm = p; - a_dec(&cm->c->_c_waiters); + unwait(cm->c, cm->m); pthread_mutex_lock(cm->m); } @@ -22,6 +37,8 @@ int pthread_cond_timedwait(pthread_cond_t *c, pthread_mutex_t *m, const struct t pthread_testcancel(); + if (c->_c_mutex != (void *)-1) c->_c_mutex = m; + a_inc(&c->_c_waiters); c->_c_block = tid = pthread_self()->tid; @@ -31,7 +48,7 @@ int pthread_cond_timedwait(pthread_cond_t *c, pthread_mutex_t *m, const struct t while (c->_c_block == tid && (!e || e==EINTR)); if (e == EINTR) e = 0; - a_dec(&c->_c_waiters); + unwait(c, m); if ((r=pthread_mutex_lock(m))) return r; |