X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=src%2Fthread%2Fpthread_mutex_timedlock.c;h=9279fc54308ad6d8b1e1b6ada6ffb32f91c1fa15;hb=b1dfb734a45d4f74c7a24c5f07d37f7e74451802;hp=0f171c0034d421976f0413eb642f3aa85440084c;hpb=c62dfe61611cee4b9b2667e1aec8a20385bc5c55;p=musl diff --git a/src/thread/pthread_mutex_timedlock.c b/src/thread/pthread_mutex_timedlock.c index 0f171c00..9279fc54 100644 --- a/src/thread/pthread_mutex_timedlock.c +++ b/src/thread/pthread_mutex_timedlock.c @@ -1,5 +1,58 @@ #include "pthread_impl.h" +#define IS32BIT(x) !((x)+0x80000000ULL>>32) +#define CLAMP(x) (int)(IS32BIT(x) ? (x) : 0x7fffffffU+((0ULL+(x))>>63)) + +static int __futex4(volatile void *addr, int op, int val, const struct timespec *to) +{ +#ifdef SYS_futex_time64 + time_t s = to ? to->tv_sec : 0; + long ns = to ? to->tv_nsec : 0; + int r = -ENOSYS; + if (SYS_futex == SYS_futex_time64 || !IS32BIT(s)) + r = __syscall(SYS_futex_time64, addr, op, val, + to ? ((long long[]){s, ns}) : 0); + if (SYS_futex == SYS_futex_time64 || r!=-ENOSYS) return r; + to = to ? (void *)(long[]){CLAMP(s), ns} : 0; +#endif + return __syscall(SYS_futex, addr, op, val, to); +} + +static int pthread_mutex_timedlock_pi(pthread_mutex_t *restrict m, const struct timespec *restrict at) +{ + int type = m->_m_type; + int priv = (type & 128) ^ 128; + pthread_t self = __pthread_self(); + int e; + + if (!priv) self->robust_list.pending = &m->_m_next; + + do e = -__futex4(&m->_m_lock, FUTEX_LOCK_PI|priv, 0, at); + while (e==EINTR); + if (e) self->robust_list.pending = 0; + + switch (e) { + case 0: + /* Catch spurious success for non-robust mutexes. */ + if (!(type&4) && ((m->_m_lock & 0x40000000) || m->_m_waiters)) { + a_store(&m->_m_waiters, -1); + __syscall(SYS_futex, &m->_m_lock, FUTEX_UNLOCK_PI|priv); + self->robust_list.pending = 0; + break; + } + /* Signal to trylock that we already have the lock. */ + m->_m_count = -1; + return __pthread_mutex_trylock(m); + case ETIMEDOUT: + return e; + case EDEADLK: + if ((type&3) == PTHREAD_MUTEX_ERRORCHECK) return e; + } + do e = __timedwait(&(int){0}, 0, CLOCK_REALTIME, at, 1); + while (e != ETIMEDOUT); + return e; +} + int __pthread_mutex_timedlock(pthread_mutex_t *restrict m, const struct timespec *restrict at) { if ((m->_m_type&15) == PTHREAD_MUTEX_NORMAL @@ -11,6 +64,8 @@ int __pthread_mutex_timedlock(pthread_mutex_t *restrict m, const struct timespec r = __pthread_mutex_trylock(m); if (r != EBUSY) return r; + + if (type&8) return pthread_mutex_timedlock_pi(m, at); int spins = 100; while (spins-- && m->_m_lock && !m->_m_waiters) a_spin();