fix pthread_cond_wait paired with with priority-inheritance mutex

[musl] / src / thread / pthread_cond_timedwait.c

diff --git a/src/thread/pthread_cond_timedwait.c b/src/thread/pthread_cond_timedwait.c
index d150124..f5f37af 100644 (file)
--- a/src/thread/pthread_cond_timedwait.c
+++ b/src/thread/pthread_cond_timedwait.c
@@ -146,14 +146,13 @@ relock:
 
        if (oldstate == WAITING) goto done;
 
-       if (!node.next) a_inc(&m->_m_waiters);
-
        /* Unlock the barrier that's holding back the next waiter, and
         * either wake it or requeue it to the mutex. */
-       if (node.prev)
-               unlock_requeue(&node.prev->barrier, &m->_m_lock, m->_m_type & 128);
-       else
-               a_dec(&m->_m_waiters);
+       if (node.prev) {
+               int val = m->_m_lock;
+               if (val>0) a_cas(&m->_m_lock, val, val|0x80000000);
+               unlock_requeue(&node.prev->barrier, &m->_m_lock, m->_m_type & (8|128));
+       }
 
        /* Since a signal was consumed, cancellation is not permitted. */
        if (e == ECANCELED) e = 0;