diff options
Diffstat (limited to 'nptl/pthread_mutex_timedlock.c')
-rw-r--r-- | nptl/pthread_mutex_timedlock.c | 382 |
1 files changed, 14 insertions, 368 deletions
diff --git a/nptl/pthread_mutex_timedlock.c b/nptl/pthread_mutex_timedlock.c index 8fd681c6ef..1cd2c7e606 100644 --- a/nptl/pthread_mutex_timedlock.c +++ b/nptl/pthread_mutex_timedlock.c @@ -1,4 +1,4 @@ -/* Copyright (C) 2002,2003,2004,2005,2006,2007 Free Software Foundation, Inc. +/* Copyright (C) 2002, 2003, 2004 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Ulrich Drepper <drepper@redhat.com>, 2002. @@ -17,12 +17,9 @@ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. */ -#include <assert.h> #include <errno.h> -#include <time.h> #include "pthreadP.h" #include <lowlevellock.h> -#include <not-cancel.h> int @@ -30,14 +27,13 @@ pthread_mutex_timedlock (mutex, abstime) pthread_mutex_t *mutex; const struct timespec *abstime; { - int oldval; pid_t id = THREAD_GETMEM (THREAD_SELF, tid); int result = 0; /* We must not check ABSTIME here. If the thread does not block abstime must not be checked for a valid value. */ - switch (__builtin_expect (mutex->__data.__kind, PTHREAD_MUTEX_TIMED_NP)) + switch (mutex->__data.__kind) { /* Recursive mutex. */ case PTHREAD_MUTEX_RECURSIVE_NP: @@ -53,25 +49,29 @@ pthread_mutex_timedlock (mutex, abstime) goto out; } + else + { + /* We have to get the mutex. */ + result = lll_mutex_timedlock (mutex->__data.__lock, abstime); - /* We have to get the mutex. */ - result = lll_mutex_timedlock (mutex->__data.__lock, abstime); - - if (result != 0) - goto out; + if (result != 0) + goto out; - /* Only locked once so far. */ - mutex->__data.__count = 1; + /* Only locked once so far. */ + mutex->__data.__count = 1; + } break; /* Error checking mutex. */ case PTHREAD_MUTEX_ERRORCHECK_NP: /* Check whether we already hold the mutex. */ - if (__builtin_expect (mutex->__data.__owner == id, 0)) + if (mutex->__data.__owner == id) return EDEADLK; /* FALLTHROUGH */ + default: + /* Correct code cannot set any other type. */ case PTHREAD_MUTEX_TIMED_NP: simple: /* Normal mutex. */ @@ -104,360 +104,6 @@ pthread_mutex_timedlock (mutex, abstime) mutex->__data.__spins += (cnt - mutex->__data.__spins) / 8; } break; - - case PTHREAD_MUTEX_ROBUST_RECURSIVE_NP: - case PTHREAD_MUTEX_ROBUST_ERRORCHECK_NP: - case PTHREAD_MUTEX_ROBUST_NORMAL_NP: - case PTHREAD_MUTEX_ROBUST_ADAPTIVE_NP: - THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, - &mutex->__data.__list.__next); - - oldval = mutex->__data.__lock; - do - { - again: - if ((oldval & FUTEX_OWNER_DIED) != 0) - { - /* The previous owner died. Try locking the mutex. */ - int newval = id | (oldval & FUTEX_WAITERS); - - newval - = atomic_compare_and_exchange_val_acq (&mutex->__data.__lock, - newval, oldval); - if (newval != oldval) - { - oldval = newval; - goto again; - } - - /* We got the mutex. */ - mutex->__data.__count = 1; - /* But it is inconsistent unless marked otherwise. */ - mutex->__data.__owner = PTHREAD_MUTEX_INCONSISTENT; - - ENQUEUE_MUTEX (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; - } - - /* Check whether we already hold the mutex. */ - if (__builtin_expect ((oldval & FUTEX_TID_MASK) == id, 0)) - { - if (mutex->__data.__kind - == PTHREAD_MUTEX_ROBUST_ERRORCHECK_NP) - { - THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, - NULL); - return EDEADLK; - } - - if (mutex->__data.__kind - == PTHREAD_MUTEX_ROBUST_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; - } - } - - result = lll_robust_mutex_timedlock (mutex->__data.__lock, abstime, - id); - - if (__builtin_expect (mutex->__data.__owner - == PTHREAD_MUTEX_NOTRECOVERABLE, 0)) - { - /* This mutex is now not recoverable. */ - mutex->__data.__count = 0; - lll_mutex_unlock (mutex->__data.__lock); - THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); - return ENOTRECOVERABLE; - } - - if (result == ETIMEDOUT || result == EINVAL) - goto out; - - oldval = result; - } - while ((oldval & FUTEX_OWNER_DIED) != 0); - - mutex->__data.__count = 1; - ENQUEUE_MUTEX (mutex); - 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_not_cancel (&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; - - case PTHREAD_MUTEX_PP_RECURSIVE_NP: - case PTHREAD_MUTEX_PP_ERRORCHECK_NP: - case PTHREAD_MUTEX_PP_NORMAL_NP: - case PTHREAD_MUTEX_PP_ADAPTIVE_NP: - { - int kind = mutex->__data.__kind & PTHREAD_MUTEX_KIND_MASK_NP; - - oldval = mutex->__data.__lock; - - /* Check whether we already hold the mutex. */ - if (mutex->__data.__owner == id) - { - if (kind == PTHREAD_MUTEX_ERRORCHECK_NP) - return EDEADLK; - - if (kind == PTHREAD_MUTEX_RECURSIVE_NP) - { - /* Just bump the counter. */ - if (__builtin_expect (mutex->__data.__count + 1 == 0, 0)) - /* Overflow of the counter. */ - return EAGAIN; - - ++mutex->__data.__count; - - return 0; - } - } - - int oldprio = -1, ceilval; - do - { - int ceiling = (oldval & PTHREAD_MUTEX_PRIO_CEILING_MASK) - >> PTHREAD_MUTEX_PRIO_CEILING_SHIFT; - - if (__pthread_current_priority () > ceiling) - { - result = EINVAL; - failpp: - if (oldprio != -1) - __pthread_tpp_change_priority (oldprio, -1); - return result; - } - - result = __pthread_tpp_change_priority (oldprio, ceiling); - if (result) - return result; - - ceilval = ceiling << PTHREAD_MUTEX_PRIO_CEILING_SHIFT; - oldprio = ceiling; - - oldval - = atomic_compare_and_exchange_val_acq (&mutex->__data.__lock, - ceilval | 1, ceilval); - - if (oldval == ceilval) - break; - - do - { - oldval - = atomic_compare_and_exchange_val_acq (&mutex->__data.__lock, - ceilval | 2, - ceilval | 1); - - if ((oldval & PTHREAD_MUTEX_PRIO_CEILING_MASK) != ceilval) - break; - - if (oldval != ceilval) - { - /* Reject invalid timeouts. */ - if (abstime->tv_nsec < 0 || abstime->tv_nsec >= 1000000000) - { - result = EINVAL; - goto failpp; - } - - struct timeval tv; - struct timespec rt; - - /* Get the current time. */ - (void) __gettimeofday (&tv, NULL); - - /* Compute relative timeout. */ - rt.tv_sec = abstime->tv_sec - tv.tv_sec; - rt.tv_nsec = abstime->tv_nsec - tv.tv_usec * 1000; - if (rt.tv_nsec < 0) - { - rt.tv_nsec += 1000000000; - --rt.tv_sec; - } - - /* Already timed out? */ - if (rt.tv_sec < 0) - { - result = ETIMEDOUT; - goto failpp; - } - - lll_futex_timed_wait (&mutex->__data.__lock, - ceilval | 2, &rt); - } - } - while (atomic_compare_and_exchange_val_acq (&mutex->__data.__lock, - ceilval | 2, ceilval) - != ceilval); - } - while ((oldval & PTHREAD_MUTEX_PRIO_CEILING_MASK) != ceilval); - - assert (mutex->__data.__owner == 0); - mutex->__data.__count = 1; - } - break; - - default: - /* Correct code cannot set any other type. */ - return EINVAL; } if (result == 0) |