-/* Copyright (C) 2002, 2003, 2004 Free Software Foundation, Inc.
+/* Copyright (C) 2002-2007, 2008 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
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
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 (mutex->__data.__kind)
+ switch (__builtin_expect (PTHREAD_MUTEX_TYPE (mutex),
+ PTHREAD_MUTEX_TIMED_NP))
{
/* Recursive mutex. */
case PTHREAD_MUTEX_RECURSIVE_NP:
goto out;
}
- else
- {
- /* We have to get the mutex. */
- result = lll_mutex_timedlock (mutex->__data.__lock, abstime);
- if (result != 0)
- goto out;
+ /* We have to get the mutex. */
+ result = lll_timedlock (mutex->__data.__lock, abstime,
+ PTHREAD_MUTEX_PSHARED (mutex));
- /* Only locked once so far. */
- mutex->__data.__count = 1;
- }
+ if (result != 0)
+ goto out;
+
+ /* 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 (mutex->__data.__owner == id)
+ if (__builtin_expect (mutex->__data.__owner == id, 0))
return EDEADLK;
/* FALLTHROUGH */
- default:
- /* Correct code cannot set any other type. */
case PTHREAD_MUTEX_TIMED_NP:
simple:
/* Normal mutex. */
- result = lll_mutex_timedlock (mutex->__data.__lock, abstime);
+ result = lll_timedlock (mutex->__data.__lock, abstime,
+ PTHREAD_MUTEX_PSHARED (mutex));
break;
case PTHREAD_MUTEX_ADAPTIVE_NP:
if (! __is_smp)
goto simple;
- if (lll_mutex_trylock (mutex->__data.__lock) != 0)
+ if (lll_trylock (mutex->__data.__lock) != 0)
{
int cnt = 0;
int max_cnt = MIN (MAX_ADAPTIVE_COUNT,
{
if (cnt++ >= max_cnt)
{
- result = lll_mutex_timedlock (mutex->__data.__lock, abstime);
+ result = lll_timedlock (mutex->__data.__lock, abstime,
+ PTHREAD_MUTEX_PSHARED (mutex));
break;
}
BUSY_WAIT_NOP;
#endif
}
- while (lll_mutex_trylock (mutex->__data.__lock) != 0);
+ while (lll_trylock (mutex->__data.__lock) != 0);
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))
+ {
+ int kind = PTHREAD_MUTEX_TYPE (mutex);
+ if (kind == PTHREAD_MUTEX_ROBUST_ERRORCHECK_NP)
+ {
+ THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending,
+ NULL);
+ return EDEADLK;
+ }
+
+ if (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_timedlock (mutex->__data.__lock, abstime, id,
+ PTHREAD_ROBUST_MUTEX_PSHARED (mutex));
+
+ if (__builtin_expect (mutex->__data.__owner
+ == PTHREAD_MUTEX_NOTRECOVERABLE, 0))
+ {
+ /* This mutex is now not recoverable. */
+ mutex->__data.__count = 0;
+ lll_unlock (mutex->__data.__lock,
+ PTHREAD_ROBUST_MUTEX_PSHARED (mutex));
+ 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. */
+ int private = (robust
+ ? PTHREAD_ROBUST_MUTEX_PSHARED (mutex)
+ : PTHREAD_MUTEX_PSHARED (mutex));
+ INTERNAL_SYSCALL_DECL (__err);
+
+ int e = INTERNAL_SYSCALL (futex, __err, 4, &mutex->__data.__lock,
+ __lll_private_flag (FUTEX_LOCK_PI,
+ private), 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,
+ __lll_private_flag (FUTEX_UNLOCK_PI,
+ PTHREAD_ROBUST_MUTEX_PSHARED (mutex)),
+ 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,
+ PTHREAD_MUTEX_PSHARED (mutex));
+ }
+ }
+ 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)
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