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| author | yamt <yamt@NetBSD.org> | 2013-03-06 11:31:34 +0000 |
|---|---|---|
| committer | yamt <yamt@NetBSD.org> | 2013-03-06 11:31:34 +0000 |
| commit | 10ffc735931f4e53bb7a0e007410c4853c1e6eae (patch) | |
| tree | 75619a5f00a8ff00d58a42ff7d4b52223dc8124a /lib/libpthread | |
| parent | 797999c3d285d9c5e6cd381e50257718ab73e49f (diff) | |
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Diffstat (limited to 'lib/libpthread')
| -rw-r--r-- | lib/libpthread/pthread_mutex.c | 22 |
1 files changed, 19 insertions, 3 deletions
diff --git a/lib/libpthread/pthread_mutex.c b/lib/libpthread/pthread_mutex.c index 6b2c8d83873..04fe5d9c3fd 100644 --- a/lib/libpthread/pthread_mutex.c +++ b/lib/libpthread/pthread_mutex.c @@ -1,4 +1,4 @@ -/* $NetBSD: pthread_mutex.c,v 1.54 2012/08/16 04:49:47 matt Exp $ */ +/* $NetBSD: pthread_mutex.c,v 1.55 2013/03/06 11:31:34 yamt Exp $ */ /*- * Copyright (c) 2001, 2003, 2006, 2007, 2008 The NetBSD Foundation, Inc. @@ -47,7 +47,7 @@ */ #include <sys/cdefs.h> -__RCSID("$NetBSD: pthread_mutex.c,v 1.54 2012/08/16 04:49:47 matt Exp $"); +__RCSID("$NetBSD: pthread_mutex.c,v 1.55 2013/03/06 11:31:34 yamt Exp $"); #include <sys/types.h> #include <sys/lwpctl.h> @@ -130,7 +130,6 @@ pthread_mutex_init(pthread_mutex_t *ptm, const pthread_mutexattr_t *attr) return 0; } - int pthread_mutex_destroy(pthread_mutex_t *ptm) { @@ -465,6 +464,12 @@ pthread__mutex_unlock_slow(pthread_mutex_t *ptm) return error; } +/* + * pthread__mutex_wakeup: unpark threads waiting for us + * + * unpark threads on the ptm->ptm_waiters list and self->pt_waiters. + */ + static void pthread__mutex_wakeup(pthread_t self, pthread_mutex_t *ptm) { @@ -530,6 +535,7 @@ pthread__mutex_wakeup(pthread_t self, pthread_mutex_t *ptm) } } } + int pthread_mutexattr_init(pthread_mutexattr_t *attr) { @@ -578,6 +584,16 @@ pthread_mutexattr_settype(pthread_mutexattr_t *attr, int type) } } +/* + * pthread__mutex_deferwake: try to defer unparking threads in self->pt_waiters + * + * In order to avoid unnecessary contention on the interlocking mutex, + * we defer waking up threads until we unlock the mutex. The threads will + * be woken up when the calling thread (self) releases the first mutex with + * MUTEX_DEFERRED_BIT set. It likely be the mutex 'ptm', but no problem + * even if it isn't. + */ + void pthread__mutex_deferwake(pthread_t self, pthread_mutex_t *ptm) { |
