[BZ #14652]
When a thread waiting in pthread_cond_wait with a PI mutex is
cancelled after it has returned successfully from the futex syscall
but just before async cancellation is disabled, it enters its
cancellation handler with the mutex held and simply calling a
mutex_lock again will result in a deadlock. Hence, it is necessary to
see if the thread owns the lock and try to lock it only if it doesn't.
* pthread_mutex_lock.c: Use it instead of PTHREAD_MUTEX_PSHARED when
dealing with robust mutexes.
* pthread_mutex_timedlock.c: Likewise.
* pthread_mutex_trylock.c: Likewise.
* pthread_mutex_unlock.c: Likewise.
* sysdeps/unix/sysv/linux/pthread_mutex_cond_lock.c: Likewise.
2007-08-06 Jakub Jelinek <jakub@redhat.com>
* pthreadP.h (PTHREAD_MUTEX_PSHARED_BIT): Define.
(PTHREAD_MUTEX_TYPE): Mask __kind with 127.
(PTHREAD_MUTEX_PSHARED): Define.
* pthread_mutex_init.c (__pthread_mutex_init): Set
PTHREAD_MUTEX_PSHARED_BIT for pshared or robust
mutexes.
* pthread_mutex_lock.c (LLL_MUTEX_LOCK): Take mutex as argument
instead of its __data.__lock field, pass PTHREAD_MUTEX_PSHARED
as second argument to lll_lock.
(LLL_MUTEX_TRYLOCK): Take mutex as argument
instead of its __data.__lock field.
(LLL_ROBUST_MUTEX_LOCK): Take mutex as argument instead of its
__data.__lock field, pass PTHREAD_MUTEX_PSHARED as second argument
to lll_robust_lock.
(__pthread_mutex_lock): Update LLL_MUTEX_LOCK, LLL_MUTEX_TRYLOCK,
LLL_ROBUST_MUTEX_LOCK users, use PTHREAD_MUTEX_TYPE (mutex)
instead of mutex->__data.__kind directly, pass
PTHREAD_MUTEX_PSHARED (mutex) to lll_unlock and lll_futex_wait.
* pthread_mutex_trylock.c (__pthread_mutex_trylock): Use
PTHREAD_MUTEX_TYPE (mutex) instead of mutex->__data.__kind
directly, pass PTHREAD_MUTEX_PSHARED (mutex) to lll_unlock.
(pthread_mutex_timedlock): Pass PTHREAD_MUTEX_PSHARED (mutex)
to lll_timedlock, lll_robust_timedlock, lll_unlock and
lll_futex_timed_wait. Use PTHREAD_MUTEX_TYPE (mutex) instead
of mutex->__data.__kind directly.
* pthread_mutex_timedlock.c (pthread_mutex_timedlock): Pass
PTHREAD_MUTEX_PSHARED (mutex) to lll_timedlock,
lll_robust_timedlock, lll_unlock and lll_futex_timed_wait. Use
PTHREAD_MUTEX_TYPE (mutex) instead of mutex->__data.__kind directly.
* pthread_mutex_unlock.c (__pthread_mutex_unlock_usercnt): Pass
PTHREAD_MUTEX_PSHARED (mutex) to lll_unlock, lll_robust_unlock
and lll_futex_wake.
* pthread_mutex_setprioceiling.c (pthread_mutex_setprioceiling): Pass
PTHREAD_MUTEX_PSHARED (mutex) to lll_futex_wait and lll_futex_wake.
Use PTHREAD_MUTEX_TYPE (mutex) instead of mutex->__data.__kind
directly.
* sysdeps/unix/sysv/linux/pthread_mutex_cond_lock.c (LLL_MUTEX_LOCK):
Take mutex as argument instead of its __data.__lock field, pass
PTHREAD_MUTEX_PSHARED as second argument to lll_cond_lock.
(LLL_MUTEX_TRYLOCK): Take mutex as argument instead of its
__data.__lock field.
(LLL_ROBUST_MUTEX_LOCK): Take mutex as argument instead of its
__data.__lock field, pass PTHREAD_MUTEX_PSHARED as second argument
to lll_robust_cond_lock.
* pthread_cond_broadcast.c (__pthread_cond_broadcast): Add pshared
variable, pass it to lll_lock, lll_unlock, lll_futex_requeue and
lll_futex_wake. Don't use lll_futex_requeue if dependent mutex
has PTHREAD_MUTEX_PSHARED_BIT bit set in its __data.__kind.
* pthread_cond_destroy.c (__pthread_cond_destroy): Add pshared
variable, pass it to lll_lock, lll_unlock, lll_futex_wake and
lll_futex_wait.
* pthread_cond_signal.c (__pthread_cond_signal): Add pshared
variable, pass it to lll_lock, lll_unlock, lll_futex_wake_unlock and
lll_futex_wake.
* pthread_cond_timedwait.c (__pthread_cond_wait): Add
pshared variable, pass it to lll_lock, lll_unlock,
lll_futex_timedwait and lll_futex_wake.
* pthread_cond_wait.c (__condvar_cleanup, __pthread_cond_wait): Add
pshared variable, pass it to lll_lock, lll_unlock, lll_futex_wait
and lll_futex_wake.
* sysdeps/unix/sysv/linux/alpha/lowlevellock.h (lll_futex_requeue,
lll_futex_wake_unlock): Add private argument, use __lll_private_flag
macro.
* sysdeps/unix/sysv/linux/ia64/lowlevellock.h (lll_futex_requeue,
lll_futex_wake_unlock): Likewise.
* sysdeps/unix/sysv/linux/powerpc/lowlevellock.h (lll_futex_requeue):
Likewise.
* sysdeps/unix/sysv/linux/sparc/lowlevellock.h (lll_futex_requeue,
lll_futex_wake_unlock): Likewise.
* sysdeps/unix/sysv/linux/x86_64/lowlevellock.h (lll_futex_requeue):
Likewise.
* sysdeps/unix/sysv/linux/s390/lowlevellock.h (lll_futex_requeue,
lll_futex_wake_unlock): Likewise.
(lll_futex_wake): Fix a typo.
* sysdeps/unix/sysv/linux/pthread-pi-defines.sym (PS_BIT): Add.
* sysdeps/unix/sysv/linux/x86_64/pthread_cond_broadcast.S
(__pthread_cond_broadcast): Pass LLL_PRIVATE to lll_* and or
FUTEX_PRIVATE_FLAG into SYS_futex op if cv is process private.
Don't use FUTEX_CMP_REQUEUE if dep_mutex is not process private.
* sysdeps/unix/sysv/linux/x86_64/pthread_cond_signal.S
(__pthread_cond_signal): Pass LLL_PRIVATE to lll_* and or
FUTEX_PRIVATE_FLAG into SYS_futex op if cv is process private.
* sysdeps/unix/sysv/linux/x86_64/pthread_cond_timedwait.S
(__pthread_cond_timedwait): Likewise.
* sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:
(__condvar_cleanup, __pthread_cond_wait): Likewise.
