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This commit is contained in:
Jeff Hill
2003-01-08 01:02:31 +00:00
parent 2ca9b78d56
commit 7cf6e3bcdd
1 changed files with 8 additions and 2 deletions
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10
src/libCom/osi/os/posix/osdMutex.c
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@@ -43,7 +43,7 @@ if(status) { \
/* Three completely different implementations are provided below
* If support is available for _POSIX_SPIN_LOCK is available
* then pthread_spin is used
* and enabled then pthread_spin is used
* If support is available for PTHREAD_MUTEX_RECURSIVE then
* only pthread_mutex is used.
* If support is not available for PTHREAD_MUTEX_RECURSIVE then
@@ -52,6 +52,12 @@ if(status) { \
#if defined ( _POSIX_SPIN_LOCKS ) && ( _POSIX_SPIN_LOCKS ) >= 200112L && EPICS_TEST_SPINLOCKS
/*
* !!!! the following is not safe on multi processor systems !!!!
* The problem is that "owner" and "owned" flags must not be accessed
* on a MP system w/o taking a lock and enforcing a memory barrier.
*/
typedef struct epicsMutexOSD {
pthread_spinlock_t lock;
pthread_t owner;
@@ -121,7 +127,7 @@ epicsMutexLockStatus epicsMutexOsdTryLock(struct epicsMutexOSD * pmutex)
if ( pthreadStatus == EBUSY ) return ( epicsMutexLockTimeout );
checkStatusQuit ( pthreadStatus,
"pthread_spin_trylock", "epicsMutexOsdTryLock" );
}
}
pmutex->owned = 1;
pmutex->owner = self;
}