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author | Ulrich Drepper <drepper@redhat.com> | 2006-07-29 04:42:09 +0000 |
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committer | Ulrich Drepper <drepper@redhat.com> | 2006-07-29 04:42:09 +0000 |
commit | df47504c78f82b9c975b2a48a6c8b6dd73a79ce1 (patch) | |
tree | 6706cdb46e20a69b3a4b4bffa9a29db9eeaff9c2 /nptl/pthread_mutex_trylock.c | |
parent | 6822f05652c50c63cdaacffd41b5ad2db0f027ce (diff) | |
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2006-07-28 Ulrich Drepper <drepper@redhat.com>
Jakub Jelinek <jakub@redhat.com>
* descr.h: Change ENQUEUE_MUTEX and DEQUEUE_MUTEX for bit 0
notification of PI mutex. Add ENQUEUE_MUTEX_PI.
* pthreadP.h: Define PTHREAD_MUTEX_PI_* macros for PI mutex types.
* pthread_mutex_setprioceilining.c: Adjust for mutex type name change.
* pthread_mutex_init.c: Add support for priority inheritance mutex.
* pthread_mutex_lock.c: Likewise.
* pthread_mutex_timedlock.c: Likewise.
* pthread_mutex_trylock.c: Likewise.
* pthread_mutex_unlock.c: Likewise.
* sysdeps/pthread/pthread_cond_broadcast.c: For PI mutexes wake
all mutexes.
* sysdeps/unix/sysv/linux/i386/i486/pthread_cond_broadcast.c: Likewise.
* sysdeps/unix/sysv/linux/x86_64/pthread_cond_broadcast.c: Likewise.
* sysdeps/unix/sysv/linux/pthread-pi-defines.sym: New file.
* sysdeps/unix/sysv/linux/Makefile (gen-as-const-header): Add
pthread-pi-defines.sym.
* sysdeps/unix/sysv/linux/i386/lowlevellock.h: Define FUTEX_LOCK_PI,
FUTEX_UNLOCK_PI, and FUTEX_TRYLOCK_PI.
* sysdeps/unix/sysv/linux/x86_64/lowlevellock.h: Likewise.
* sysdeps/unix/sysv/linux/bits/posix_opt.h: Define
_POSIX_THREAD_PRIO_INHERIT to 200112L.
* tst-mutex1.c: Adjust to allow use in PI mutex test.
* tst-mutex2.c: Likewise.
* tst-mutex3.c: Likewise.
* tst-mutex4.c: Likewise.
* tst-mutex5.c: Likewise.
* tst-mutex6.c: Likewise.
* tst-mutex7.c: Likewise.
* tst-mutex7a.c: Likewise.
* tst-mutex8.c: Likewise.
* tst-mutex9.c: Likewise.
* tst-robust1.c: Likewise.
* tst-robust7.c: Likewise.
* tst-robust8.c: Likewise.
* tst-mutexpi1.c: New file.
* tst-mutexpi2.c: New file.
* tst-mutexpi3.c: New file.
* tst-mutexpi4.c: New file.
* tst-mutexpi5.c: New file.
* tst-mutexpi6.c: New file.
* tst-mutexpi7.c: New file.
* tst-mutexpi7a.c: New file.
* tst-mutexpi8.c: New file.
* tst-mutexpi9.c: New file.
* tst-robust1.c: New file.
* tst-robust2.c: New file.
* tst-robust3.c: New file.
* tst-robust4.c: New file.
* tst-robust5.c: New file.
* tst-robust6.c: New file.
* tst-robust7.c: New file.
* tst-robust8.c: New file.
* Makefile (tests): Add the new tests.
* pthread_create.c (start_thread): Add some casts to avoid warnings.
* pthread_mutex_destroy.c: Remove unneeded label.
Diffstat (limited to 'nptl/pthread_mutex_trylock.c')
-rw-r--r-- | nptl/pthread_mutex_trylock.c | 124 |
1 files changed, 123 insertions, 1 deletions
diff --git a/nptl/pthread_mutex_trylock.c b/nptl/pthread_mutex_trylock.c index 148a6e9..f3a1856 100644 --- a/nptl/pthread_mutex_trylock.c +++ b/nptl/pthread_mutex_trylock.c @@ -152,7 +152,6 @@ __pthread_mutex_trylock (mutex) return EBUSY; } - robust: if (__builtin_expect (mutex->__data.__owner == PTHREAD_MUTEX_NOTRECOVERABLE, 0)) { @@ -175,6 +174,129 @@ __pthread_mutex_trylock (mutex) return 0; + 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) + { + if ((oldval & FUTEX_OWNER_DIED) == 0) + { + THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); + + return EBUSY; + } + + assert (robust); + + /* The mutex owner died. The kernel will now take care of + everything. */ + INTERNAL_SYSCALL_DECL (__err); + int e = INTERNAL_SYSCALL (futex, __err, 4, &mutex->__data.__lock, + FUTEX_TRYLOCK_PI, 0, 0); + + if (INTERNAL_SYSCALL_ERROR_P (e, __err) + && INTERNAL_SYSCALL_ERRNO (e, __err) == EWOULDBLOCK) + { + THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); + + return EBUSY; + } + + oldval = mutex->__data.__lock; + } + + 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 (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; + } + + if (robust) + { + ENQUEUE_MUTEX_PI (mutex); + THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); + } + + mutex->__data.__owner = id; + ++mutex->__data.__nusers; + mutex->__data.__count = 1; + + return 0; + } + default: /* Correct code cannot set any other type. */ return EINVAL; |