From a311086d622d3c778e1da57cfae167c0ab1c0fb4 Mon Sep 17 00:00:00 2001 From: rpj Date: Sun, 1 Jul 2001 13:23:10 +0000 Subject: 2001-06-25 Ross Johnson * create.c (pthread_create): Add priority inheritance attributes. * mutex.c (pthread_mutex_lock): Remove some overhead for PTHREAD_MUTEX_NORMAL mutex types. Specifically, avoid calling pthread_self() and pthread_equal() to check/set the mutex owner. Introduce a new pseudo owner for this type. Test results suggest increases in speed of up to 90% for non-blocking locks. This is the default type of mutex used internally by other synchronising objects, ie. condition variables and read-write locks. The test rwlock7.c shows about a 30-35% speed increase over snapshot 2001-06-06. The price of this is that the application developer must ensure correct behaviour, or explicitly set the mutex to a safer type such as PTHREAD_MUTEX_ERRORCHECK. For example, PTHREAD_MUTEX_NORMAL (or PTHREAD_MUTEX_DEFAULT) type mutexes will not return an error if a thread which is not the owner calls pthread_mutex_unlock. The call will succeed in unlocking the mutex if it is currently locked, but a subsequent unlock by the true owner will then fail with EPERM. This is however consistent with some other implementations. (pthread_mutex_unlock): Likewise. (pthread_mutex_trylock): Likewise. (pthread_mutex_destroy): Likewise. * attr.c (pthread_attr_init): PTHREAD_EXPLICIT_SCHED is the default inheritance attribute; THREAD_PRIORITY_NORMAL is the default priority for new threads. * sched.c (pthread_attr_setschedpolicy): Added routine. (pthread_attr_getschedpolicy): Added routine. (pthread_attr_setinheritsched): Added routine. (pthread_attr_getinheritsched): Added routine. * pthread.h (sched_rr_set_interval): Added as a macro; returns -1 with errno set to ENOSYS. 2001-06-23 Ross Johnson *sched.c (pthread_attr_setschedparam): Add priority range check. (sched_setscheduler): New function; checks for a valid pid and policy; checks for permission to set information in the target process; expects pid to be a Win32 process ID, not a process handle; the only scheduler policy allowed is SCHED_OTHER. (sched_getscheduler): Likewise, but checks for permission to query. * pthread.h (SCHED_*): Moved to sched.h as defined in the POSIX standard. * sched.h (SCHED_*): Moved from pthread.h. (pid_t): Defined if necessary. (sched_setscheduler): Defined. (sched_getscheduler): Defined. * pthread.def (sched_setscheduler): Exported. (sched_getscheduler): Likewise. 2001-06-23 Ross Johnson Contributed by - Ralf Brese * create.c (pthread_create): Set thread priority from thread attributes. --- mutex.c | 27 ++++++++++++++++++++------- 1 file changed, 20 insertions(+), 7 deletions(-) (limited to 'mutex.c') diff --git a/mutex.c b/mutex.c index b1e2693..0396e5f 100644 --- a/mutex.c +++ b/mutex.c @@ -180,8 +180,14 @@ pthread_mutex_destroy(pthread_mutex_t *mutex) * The mutex type may not be RECURSIVE therefore trylock may return EBUSY if * we already own the mutex. Here we are assuming that it's OK to destroy * a mutex that we own and have locked recursively. Is this correct? + * + * For FAST mutexes we record the owner as ANONYMOUS for speed. In this + * case we assume that the thread calling pthread_mutex_destroy() is the + * owner, if the mutex is owned at all. */ - if (result == 0 || pthread_equal( mx->ownerThread, pthread_self() ) ) + if (result == 0 + || mx->ownerThread == (pthread_t) PTW32_MUTEX_OWNER_ANONYMOUS + || pthread_equal( mx->ownerThread, pthread_self() ) ) { /* * FIXME!!! @@ -634,7 +640,9 @@ pthread_mutex_lock(pthread_mutex_t *mutex) if( 0 == InterlockedIncrement( &mx->lock_idx ) ) { mx->recursive_count = 1; - mx->ownerThread = pthread_self(); + mx->ownerThread = (mx->kind != PTHREAD_MUTEX_FAST_NP + ? pthread_self() + : (pthread_t) PTW32_MUTEX_OWNER_ANONYMOUS); } else { @@ -656,7 +664,9 @@ pthread_mutex_lock(pthread_mutex_t *mutex) { WaitForSingleObject( mx->wait_sema, INFINITE ); mx->recursive_count = 1; - mx->ownerThread = pthread_self(); + mx->ownerThread = (mx->kind != PTHREAD_MUTEX_FAST_NP + ? pthread_self() + : (pthread_t) PTW32_MUTEX_OWNER_ANONYMOUS); } } @@ -683,10 +693,11 @@ pthread_mutex_unlock(pthread_mutex_t *mutex) */ if (mx != (pthread_mutex_t) PTW32_OBJECT_AUTO_INIT) { - if (pthread_equal(mx->ownerThread, pthread_self())) + if (mx->ownerThread == (pthread_t) PTW32_MUTEX_OWNER_ANONYMOUS + || pthread_equal(mx->ownerThread, pthread_self())) { - if( mx->kind != PTHREAD_MUTEX_RECURSIVE_NP || - 0 == --mx->recursive_count ) + if( mx->kind != PTHREAD_MUTEX_RECURSIVE_NP + || 0 == --mx->recursive_count ) { mx->ownerThread = NULL; @@ -748,7 +759,9 @@ pthread_mutex_trylock(pthread_mutex_t *mutex) if( 0 == InterlockedIncrement( &mx->lock_idx ) ) { mx->recursive_count = 1; - mx->ownerThread = pthread_self(); + mx->ownerThread = (mx->kind != PTHREAD_MUTEX_FAST_NP + ? pthread_self() + : (pthread_t) PTW32_MUTEX_OWNER_ANONYMOUS); } else { -- cgit v1.2.3