diff options
Diffstat (limited to 'src/thread/pthread_mutex_trylock.c')
| -rw-r--r-- | src/thread/pthread_mutex_trylock.c | 38 |
1 files changed, 27 insertions, 11 deletions
diff --git a/src/thread/pthread_mutex_trylock.c b/src/thread/pthread_mutex_trylock.c index 783ca0c4..a24e7c58 100644 --- a/src/thread/pthread_mutex_trylock.c +++ b/src/thread/pthread_mutex_trylock.c @@ -3,21 +3,28 @@ int __pthread_mutex_trylock_owner(pthread_mutex_t *m) { int old, own; - int type = m->_m_type & 15; + int type = m->_m_type; pthread_t self = __pthread_self(); int tid = self->tid; old = m->_m_lock; - own = old & 0x7fffffff; - if (own == tid && (type&3) == PTHREAD_MUTEX_RECURSIVE) { - if ((unsigned)m->_m_count >= INT_MAX) return EAGAIN; - m->_m_count++; - return 0; + own = old & 0x3fffffff; + if (own == tid) { + if ((type&8) && m->_m_count<0) { + old &= 0x40000000; + m->_m_count = 0; + goto success; + } + if ((type&3) == PTHREAD_MUTEX_RECURSIVE) { + if ((unsigned)m->_m_count >= INT_MAX) return EAGAIN; + m->_m_count++; + return 0; + } } - if (own == 0x7fffffff) return ENOTRECOVERABLE; - if (own && (!(own & 0x40000000) || !(type & 4))) return EBUSY; + if (own == 0x3fffffff) return ENOTRECOVERABLE; + if (own || (old && !(type & 4))) return EBUSY; - if (m->_m_type & 128) { + if (type & 128) { if (!self->robust_list.off) { self->robust_list.off = (char*)&m->_m_lock-(char *)&m->_m_next; __syscall(SYS_set_robust_list, &self->robust_list, 3*sizeof(long)); @@ -25,12 +32,22 @@ int __pthread_mutex_trylock_owner(pthread_mutex_t *m) if (m->_m_waiters) tid |= 0x80000000; self->robust_list.pending = &m->_m_next; } + tid |= old & 0x40000000; if (a_cas(&m->_m_lock, old, tid) != old) { self->robust_list.pending = 0; + if ((type&12)==12 && m->_m_waiters) return ENOTRECOVERABLE; return EBUSY; } +success: + if ((type&8) && m->_m_waiters) { + int priv = (type & 128) ^ 128; + __syscall(SYS_futex, &m->_m_lock, FUTEX_UNLOCK_PI|priv); + self->robust_list.pending = 0; + return (type&4) ? ENOTRECOVERABLE : EBUSY; + } + volatile void *next = self->robust_list.head; m->_m_next = next; m->_m_prev = &self->robust_list.head; @@ -39,9 +56,8 @@ int __pthread_mutex_trylock_owner(pthread_mutex_t *m) self->robust_list.head = &m->_m_next; self->robust_list.pending = 0; - if (own) { + if (old) { m->_m_count = 0; - m->_m_type |= 8; return EOWNERDEAD; } |