diff options
Diffstat (limited to 'libc/nptl/pthread_mutex_trylock.c')
| -rw-r--r-- | libc/nptl/pthread_mutex_trylock.c | 32 |
1 files changed, 29 insertions, 3 deletions
diff --git a/libc/nptl/pthread_mutex_trylock.c b/libc/nptl/pthread_mutex_trylock.c index 8f5279d2f..600c8483b 100644 --- a/libc/nptl/pthread_mutex_trylock.c +++ b/libc/nptl/pthread_mutex_trylock.c @@ -22,6 +22,16 @@ #include "pthreadP.h" #include <lowlevellock.h> +#ifndef lll_trylock_elision +#define lll_trylock_elision(a,t) lll_trylock(a) +#endif + +#ifndef DO_ELISION +#define DO_ELISION(m) 0 +#endif + +/* We don't force elision in trylock, because this can lead to inconsistent + lock state if the lock was actually busy. */ int __pthread_mutex_trylock (mutex) @@ -30,10 +40,11 @@ __pthread_mutex_trylock (mutex) int oldval; pid_t id = THREAD_GETMEM (THREAD_SELF, tid); - switch (__builtin_expect (PTHREAD_MUTEX_TYPE (mutex), + switch (__builtin_expect (PTHREAD_MUTEX_TYPE_ELISION (mutex), PTHREAD_MUTEX_TIMED_NP)) { /* Recursive mutex. */ + case PTHREAD_MUTEX_RECURSIVE_NP|PTHREAD_MUTEX_ELISION_NP: case PTHREAD_MUTEX_RECURSIVE_NP: /* Check whether we already hold the mutex. */ if (mutex->__data.__owner == id) @@ -57,10 +68,20 @@ __pthread_mutex_trylock (mutex) } break; - case PTHREAD_MUTEX_ERRORCHECK_NP: + case PTHREAD_MUTEX_TIMED_ELISION_NP: + elision: + if (lll_trylock_elision (mutex->__data.__lock, + mutex->__data.__elision) != 0) + break; + /* Don't record the ownership. */ + return 0; + case PTHREAD_MUTEX_TIMED_NP: + if (DO_ELISION (mutex)) + goto elision; + /*FALL THROUGH*/ case PTHREAD_MUTEX_ADAPTIVE_NP: - /* Normal mutex. */ + case PTHREAD_MUTEX_ERRORCHECK_NP: if (lll_trylock (mutex->__data.__lock) != 0) break; @@ -378,4 +399,9 @@ __pthread_mutex_trylock (mutex) return EBUSY; } + +#ifndef __pthread_mutex_trylock +#ifndef pthread_mutex_trylock strong_alias (__pthread_mutex_trylock, pthread_mutex_trylock) +#endif +#endif |