diff options
Diffstat (limited to 'nptl/pthread_mutex_timedlock.c')
| -rw-r--r-- | nptl/pthread_mutex_timedlock.c | 150 |
1 files changed, 147 insertions, 3 deletions
diff --git a/nptl/pthread_mutex_timedlock.c b/nptl/pthread_mutex_timedlock.c index 7c48c7ce6b..12f6c997bb 100644 --- a/nptl/pthread_mutex_timedlock.c +++ b/nptl/pthread_mutex_timedlock.c @@ -35,7 +35,7 @@ pthread_mutex_timedlock (mutex, abstime) /* We must not check ABSTIME here. If the thread does not block abstime must not be checked for a valid value. */ - switch (mutex->__data.__kind) + switch (__builtin_expect (mutex->__data.__kind, PTHREAD_MUTEX_TIMED_NP)) { /* Recursive mutex. */ case PTHREAD_MUTEX_RECURSIVE_NP: @@ -65,7 +65,7 @@ pthread_mutex_timedlock (mutex, abstime) /* Error checking mutex. */ case PTHREAD_MUTEX_ERRORCHECK_NP: /* Check whether we already hold the mutex. */ - if (mutex->__data.__owner == id) + if (__builtin_expect (mutex->__data.__owner == id, 0)) return EDEADLK; /* FALLTHROUGH */ @@ -134,7 +134,7 @@ pthread_mutex_timedlock (mutex, abstime) ENQUEUE_MUTEX (mutex); THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); - /* Note that we deliberately exist here. If we fall + /* Note that we deliberately exit here. If we fall through to the end of the function __nusers would be incremented which is not correct because the old owner has to be discounted. */ @@ -194,6 +194,150 @@ pthread_mutex_timedlock (mutex, abstime) THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); break; + case PTHREAD_MUTEX_PI_RECURSIVE_NP: + case PTHREAD_MUTEX_PI_ERRORCHECK_NP: + case PTHREAD_MUTEX_PI_NORMAL_NP: + case PTHREAD_MUTEX_PI_ADAPTIVE_NP: + case PTHREAD_MUTEX_PI_ROBUST_RECURSIVE_NP: + case PTHREAD_MUTEX_PI_ROBUST_ERRORCHECK_NP: + case PTHREAD_MUTEX_PI_ROBUST_NORMAL_NP: + case PTHREAD_MUTEX_PI_ROBUST_ADAPTIVE_NP: + { + int kind = mutex->__data.__kind & PTHREAD_MUTEX_KIND_MASK_NP; + int robust = mutex->__data.__kind & PTHREAD_MUTEX_ROBUST_NORMAL_NP; + + if (robust) + /* Note: robust PI futexes are signaled by setting bit 0. */ + THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, + (void *) (((uintptr_t) &mutex->__data.__list.__next) + | 1)); + + oldval = mutex->__data.__lock; + + /* Check whether we already hold the mutex. */ + if (__builtin_expect ((oldval & FUTEX_TID_MASK) == id, 0)) + { + if (kind == PTHREAD_MUTEX_ERRORCHECK_NP) + { + THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); + return EDEADLK; + } + + if (kind == PTHREAD_MUTEX_RECURSIVE_NP) + { + THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); + + /* Just bump the counter. */ + if (__builtin_expect (mutex->__data.__count + 1 == 0, 0)) + /* Overflow of the counter. */ + return EAGAIN; + + ++mutex->__data.__count; + + return 0; + } + } + + oldval = atomic_compare_and_exchange_val_acq (&mutex->__data.__lock, + id, 0); + + if (oldval != 0) + { + /* The mutex is locked. The kernel will now take care of + everything. The timeout value must be a relative value. + Convert it. */ + INTERNAL_SYSCALL_DECL (__err); + + int e = INTERNAL_SYSCALL (futex, __err, 4, &mutex->__data.__lock, + FUTEX_LOCK_PI, 1, abstime); + if (INTERNAL_SYSCALL_ERROR_P (e, __err)) + { + if (INTERNAL_SYSCALL_ERRNO (e, __err) == ETIMEDOUT) + return ETIMEDOUT; + + if (INTERNAL_SYSCALL_ERRNO (e, __err) == ESRCH + || INTERNAL_SYSCALL_ERRNO (e, __err) == EDEADLK) + { + assert (INTERNAL_SYSCALL_ERRNO (e, __err) != EDEADLK + || (kind != PTHREAD_MUTEX_ERRORCHECK_NP + && kind != PTHREAD_MUTEX_RECURSIVE_NP)); + /* ESRCH can happen only for non-robust PI mutexes where + the owner of the lock died. */ + assert (INTERNAL_SYSCALL_ERRNO (e, __err) != ESRCH + || !robust); + + /* Delay the thread until the timeout is reached. + Then return ETIMEDOUT. */ + struct timespec reltime; + struct timespec now; + + INTERNAL_SYSCALL (clock_gettime, __err, 2, CLOCK_REALTIME, + &now); + reltime.tv_sec = abstime->tv_sec - now.tv_sec; + reltime.tv_nsec = abstime->tv_nsec - now.tv_nsec; + if (reltime.tv_nsec < 0) + { + reltime.tv_nsec += 1000000000; + --reltime.tv_sec; + } + if (reltime.tv_sec >= 0) + while (__nanosleep_nocancel (&reltime, &reltime) != 0) + continue; + + return ETIMEDOUT; + } + + return INTERNAL_SYSCALL_ERRNO (e, __err); + } + + oldval = mutex->__data.__lock; + + assert (robust || (oldval & FUTEX_OWNER_DIED) == 0); + } + + if (__builtin_expect (oldval & FUTEX_OWNER_DIED, 0)) + { + atomic_and (&mutex->__data.__lock, ~FUTEX_OWNER_DIED); + + /* We got the mutex. */ + mutex->__data.__count = 1; + /* But it is inconsistent unless marked otherwise. */ + mutex->__data.__owner = PTHREAD_MUTEX_INCONSISTENT; + + ENQUEUE_MUTEX_PI (mutex); + THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); + + /* Note that we deliberately exit here. If we fall + through to the end of the function __nusers would be + incremented which is not correct because the old owner + has to be discounted. */ + return EOWNERDEAD; + } + + if (robust + && __builtin_expect (mutex->__data.__owner + == PTHREAD_MUTEX_NOTRECOVERABLE, 0)) + { + /* This mutex is now not recoverable. */ + mutex->__data.__count = 0; + + INTERNAL_SYSCALL_DECL (__err); + INTERNAL_SYSCALL (futex, __err, 4, &mutex->__data.__lock, + FUTEX_UNLOCK_PI, 0, 0); + + THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); + return ENOTRECOVERABLE; + } + + mutex->__data.__count = 1; + if (robust) + { + ENQUEUE_MUTEX_PI (mutex); + THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); + } + } + break; + default: /* Correct code cannot set any other type. */ return EINVAL; |