コード例 #1
0
void _ump_osu_lock_term( _ump_osu_lock_t *lock )
{
	int call_result;
	UMP_DEBUG_ASSERT_POINTER( lock );

	/** Debug lock checking: */
	/* Lock is signalled on terminate - not a guarantee, since we could be locked immediately beforehand */
	UMP_DEBUG_ASSERT( _UMP_OSU_LOCKMODE_UNDEF == lock->locked_as,
					   ("cannot terminate held lock\n") );

	call_result = pthread_mutex_destroy( &lock->mutex );
	UMP_DEBUG_ASSERT( 0 == call_result,
					   ("Incorrect mutex use detected: pthread_mutex_destroy call failed with error code %d\n", call_result) );

	/* Destroy extra state for ANY_UNLOCK type osu_locks */
	if ( lock->flags & _UMP_OSU_LOCKFLAG_ANYUNLOCK )
	{
		UMP_DEBUG_ASSERT( UMP_FALSE == lock->state, ("terminate called on locked object %p\n", lock));
		call_result = pthread_cond_destroy(&lock->condition);
		UMP_DEBUG_ASSERT( 0 == call_result,
						   ("Incorrect condition-variable use detected: pthread_cond_destroy call failed with error code %d\n", call_result) );
	}

	UMP_IGNORE(call_result);

	_ump_osu_free( lock );
}
コード例 #2
0
_ump_osu_errcode_t _ump_osu_lock_wait( _ump_osu_lock_t *lock, _ump_osu_lock_mode_t mode)
{
	/* Parameter validation */
	UMP_DEBUG_ASSERT_POINTER( lock );

	UMP_DEBUG_ASSERT( _UMP_OSU_LOCKMODE_RW == mode,
					   ("unrecognised mode, %.8X\n", mode) );

	/** @note since only one flag can be set, we use a switch statement here.
	 * Otherwise, MUST add an enum into the _ump_osu_lock_t to store the
	 * implemented lock type */
	switch ( lock->flags )
	{
	case _UMP_OSU_LOCKFLAG_STATIC:
	case _UMP_OSU_LOCKFLAG_DEFAULT:
		/* Usual Mutex type */
		{
			int call_result;
			call_result = pthread_mutex_lock( &lock->mutex );
			UMP_DEBUG_ASSERT( 0 == call_result,
							   ("pthread_mutex_lock call failed with error code %d\n", call_result));
			UMP_IGNORE( call_result );
		}

		/* DEBUG tracking of previously locked state - occurs while lock is obtained */
		UMP_DEBUG_ASSERT( _UMP_OSU_LOCKMODE_UNDEF == lock->locked_as,
						   ("This lock was already locked\n") );
		UMP_DEBUG_CODE( lock->locked_as = mode );
		break;

	case _UMP_OSU_LOCKFLAG_ANYUNLOCK:
		/** @note Use of bitflags in a case statement ONLY works because this
		 * is the ONLY flag that is supported */

		/* lock the mutex protecting access to the state field */
		pthread_mutex_lock( &lock->mutex );
		/* loop while locked (state is UMP_TRUE) */
		/* pthread_cond_wait unlocks the mutex, wait, and locks the mutex once unblocked */
		while ( UMP_TRUE == lock->state ) pthread_cond_wait( &lock->condition, &lock->mutex );

		/* DEBUG tracking of previously locked state - occurs while lock is obtained */
		UMP_DEBUG_ASSERT( _UMP_OSU_LOCKMODE_UNDEF == lock->locked_as,
						   ("This lock was already locked\n") );
		UMP_DEBUG_CODE( lock->locked_as = mode );

		/* the state is UMP_FALSE (unlocked), so we set it to UMP_TRUE to indicate that it's locked and can return knowing that we own the lock */
		lock->state = UMP_TRUE;
		/* final unlock of the mutex */
		pthread_mutex_unlock(&lock->mutex);
		break;

	default:
		UMP_DEBUG_ERROR( ("lock has incorrect flags==%.8X\n", lock->flags) );
		break;
	}

	return _UMP_OSU_ERR_OK;
}
コード例 #3
0
void _ump_osu_lock_signal( _ump_osu_lock_t *lock, _ump_osu_lock_mode_t mode )
{
	/* Parameter validation */
	UMP_DEBUG_ASSERT_POINTER( lock );

	UMP_DEBUG_ASSERT( _UMP_OSU_LOCKMODE_RW == mode,
					   ("unrecognised mode, %.8X\n", mode) );

	/** @note since only one flag can be set, we use a switch statement here.
	 * Otherwise, MUST add an enum into the _ump_osu_lock_t to store the
	 * implemented lock type */
	switch ( lock->flags )
	{
	case _UMP_OSU_LOCKFLAG_STATIC:
	case _UMP_OSU_LOCKFLAG_DEFAULT:
		/* Usual Mutex type */

		/* DEBUG tracking of previously locked state - occurs while lock is obtained */
		UMP_DEBUG_ASSERT( mode == lock->locked_as,
						   ("This lock was locked as==%.8X, but tried to unlock as mode==%.8X\n", lock->locked_as, mode));
		UMP_DEBUG_CODE( lock->locked_as = _UMP_OSU_LOCKMODE_UNDEF );

		{
			int call_result;
			call_result = pthread_mutex_unlock( &lock->mutex );
			UMP_DEBUG_ASSERT( 0 == call_result,
							   ("pthread_mutex_lock call failed with error code %d\n", call_result));
			UMP_IGNORE( call_result );
		}
		break;

	case _UMP_OSU_LOCKFLAG_ANYUNLOCK:
		/** @note Use of bitflags in a case statement ONLY works because this
		 * is the ONLY flag that is supported */

		pthread_mutex_lock(&lock->mutex);
		UMP_DEBUG_ASSERT( UMP_TRUE == lock->state, ("Unlocking a _ump_osu_lock_t %p which is not locked\n", lock));

		/* DEBUG tracking of previously locked state - occurs while lock is obtained */
		UMP_DEBUG_ASSERT( mode == lock->locked_as,
						   ("This lock was locked as==%.8X, but tried to unlock as %.8X\n", lock->locked_as, mode ));
		UMP_DEBUG_CODE( lock->locked_as = _UMP_OSU_LOCKMODE_UNDEF );

		/* mark as unlocked */
		lock->state = UMP_FALSE;

		/* signal the condition, only wake a single thread */
		pthread_cond_signal(&lock->condition);

		pthread_mutex_unlock(&lock->mutex);
		break;

	default:
		UMP_DEBUG_ERROR( ("lock has incorrect flags==%.8X\n", lock->flags) );
		break;
	}
}
コード例 #4
0
_ump_osu_errcode_t _ump_osu_lock_auto_init( _ump_osu_lock_t **pplock, _ump_osu_lock_flags_t flags, u32 initial, u32 order )
{
	int call_result;
	/* Validate parameters: */
	UMP_DEBUG_ASSERT_POINTER( pplock );

	/** @opt We don't lock the Critical Section or do anything if this is already non-null */
	if ( NULL != *pplock)
	{
		return _UMP_OSU_ERR_OK;
	}

	/* We MIGHT need to initialize it, lock the Critical Section and check again */
	call_result = pthread_mutex_lock(&static_auto_init_mutex);
	/* It would be a programming error for this to fail: */
	UMP_DEBUG_ASSERT( 0 == call_result,
					   ("failed to lock critical section\n") );

	if ( NULL != *pplock )
	{
		/*
			We caught a race condition to initialize this osu_lock.
			The other thread won the race, so the osu_lock is now initialized.
		*/
		call_result = pthread_mutex_unlock(&static_auto_init_mutex);

		UMP_DEBUG_ASSERT(0 == call_result,
						  ("failed to unlock critical section\n"));

		return _UMP_OSU_ERR_OK;
	}

	/* We're the first thread in: initialize the osu_lock */
	*pplock = _ump_osu_lock_init( flags, initial, order );

	if ( NULL == *pplock )
	{
		/* osu_lock creation failed */
		call_result = pthread_mutex_unlock(&static_auto_init_mutex);
		UMP_DEBUG_ASSERT(0 == call_result,
						  ("failed to unlock critical section\n"));

		return _UMP_OSU_ERR_FAULT;
	}


	/* osu_lock created OK */
	call_result = pthread_mutex_unlock(&static_auto_init_mutex);

	UMP_DEBUG_ASSERT(0 == call_result,
					  ("failed to unlock critical section\n"));

	UMP_IGNORE( call_result );

	return _UMP_OSU_ERR_OK;
}
コード例 #5
0
void ump_arch_close(void)
{
	_ump_osu_lock_auto_init(&ump_lock_arch, _UMP_OSU_LOCKFLAG_DEFAULT, 0, 0);

	/* Check that the lock was initialized */
	if (NULL == ump_lock_arch)
	{
		UMP_DEBUG_PRINT(1, ("UMP: ump_arch_close() failed to init lock\n"));
		return;
	}

	/* Attempt to obtain a lock */
	if (_UMP_OSU_ERR_OK !=  _ump_osu_lock_wait(ump_lock_arch, _UMP_OSU_LOCKMODE_RW))
	{
		UMP_DEBUG_PRINT(1, ("UMP: ump_arch_close() failed to acquire lock\n"));
		return;
	}

	UMP_DEBUG_ASSERT(0 < ump_ref_count, ("UMP: ump_arch_close() called while no references exist"));

	if (ump_ref_count > 0)
	{
		ump_ref_count--;

		if (0 == ump_ref_count)
		{
			_ump_osu_errcode_t retval = _ump_uku_close(&ump_uk_ctx);
			UMP_DEBUG_ASSERT(retval == _UMP_OSU_ERR_OK, ("UMP: Failed to close UMP interface"));
			UMP_IGNORE(retval);
			ump_uk_ctx = NULL;
			_ump_osu_lock_signal(ump_lock_arch, _UMP_OSU_LOCKMODE_RW);
			_ump_osu_lock_term(ump_lock_arch);   /* Not 100% thread safe, since another thread can already be waiting for this lock in ump_arch_open() */
			ump_lock_arch = NULL;
			return;
		}
	}

	/* Signal the lock so someone else can use it */
	_ump_osu_lock_signal(ump_lock_arch, _UMP_OSU_LOCKMODE_RW);
}
コード例 #6
0
_ump_osu_lock_t *_ump_osu_lock_init( _ump_osu_lock_flags_t flags, u32 initial, u32 order )
{
	_ump_osu_lock_t * lock;
	pthread_mutexattr_t mutex_attributes;

	UMP_IGNORE(order); /* order isn't implemented yet, for now callers should set it to zero. */

	/* Validate parameters: */
	/* Flags acceptable */
	UMP_DEBUG_ASSERT( 0 == ( flags & ~( _UMP_OSU_LOCKFLAG_ANYUNLOCK)),
					   ("incorrect flags or trying to initialise a statically initialized lock, %.8X\n", flags) );

	/* Parameter initial SBZ - for future expansion */
	UMP_DEBUG_ASSERT( 0 == initial,
					   ("initial must be zero\n") );

	if (0 != pthread_mutexattr_init(&mutex_attributes))
	{
		return NULL;
	}

#if UMP_DEBUG_EXTENDED_MUTEX_LOCK_CHECKING
#define UMP_PTHREADS_MUTEX_TYPE PTHREAD_MUTEX_ERRORCHECK
#else
#define UMP_PTHREADS_MUTEX_TYPE PTHREAD_MUTEX_DEFAULT
#endif

	if (0 != pthread_mutexattr_settype(&mutex_attributes, UMP_PTHREADS_MUTEX_TYPE))
	{
		/** Return NULL on failure */
		pthread_mutexattr_destroy(&mutex_attributes);
		return NULL;

	}

#undef UMP_PTHREADS_MUTEX_TYPE

	/** @opt use containing structures for the ANY_UNLOCK type, to
	 * save 2 DWORDS when not in use */
	lock = _ump_osu_malloc( sizeof(_ump_osu_lock_t) );

	if( NULL == lock )
	{
		/** Return NULL on failure */
		pthread_mutexattr_destroy(&mutex_attributes);
		return NULL;
	}

	if (0 != pthread_mutex_init( &lock->mutex, &mutex_attributes ))
	{
		pthread_mutexattr_destroy(&mutex_attributes);
		_ump_osu_free( lock );
		return NULL;
	}

	/* done with the mutexattr object */
	pthread_mutexattr_destroy(&mutex_attributes);

	/* ANY_UNLOCK type */
	if ( flags & _UMP_OSU_LOCKFLAG_ANYUNLOCK )
	{
		if (0 != pthread_cond_init( &lock->condition, NULL ))
		{
			/* cleanup */
			pthread_mutex_destroy( &lock->mutex );
			_ump_osu_free( lock );
			return NULL;
		}
		lock->state = UMP_FALSE; /* mark as unlocked by default */
	}

	lock->flags = flags;

	/** Debug lock checking */
	UMP_DEBUG_CODE( lock->locked_as = _UMP_OSU_LOCKMODE_UNDEF	);

	return lock;
}