diff options
Diffstat (limited to 'src/thread/pthread_mutex_unlock.c')
-rw-r--r-- | src/thread/pthread_mutex_unlock.c | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/src/thread/pthread_mutex_unlock.c b/src/thread/pthread_mutex_unlock.c index ea9f54dd..b66423e6 100644 --- a/src/thread/pthread_mutex_unlock.c +++ b/src/thread/pthread_mutex_unlock.c @@ -8,10 +8,11 @@ int __pthread_mutex_unlock(pthread_mutex_t *m) int type = m->_m_type & 15; int priv = (m->_m_type & 128) ^ 128; int new = 0; + int old; if (type != PTHREAD_MUTEX_NORMAL) { self = __pthread_self(); - int old = m->_m_lock; + old = m->_m_lock; int own = old & 0x3fffffff; if (own != self->tid) return EPERM; @@ -29,7 +30,16 @@ int __pthread_mutex_unlock(pthread_mutex_t *m) if (next != &self->robust_list.head) *(volatile void *volatile *) ((char *)next - sizeof(void *)) = prev; } - cont = a_swap(&m->_m_lock, new); + if (type&8) { + if (old<0 || a_cas(&m->_m_lock, old, new)!=old) { + if (new) a_store(&m->_m_waiters, -1); + __syscall(SYS_futex, &m->_m_lock, FUTEX_UNLOCK_PI|priv); + } + cont = 0; + waiters = 0; + } else { + cont = a_swap(&m->_m_lock, new); + } if (type != PTHREAD_MUTEX_NORMAL && !priv) { self->robust_list.pending = 0; __vm_unlock(); |