0,0 → 1,107 |
/* |
* Copyright (c) 2001-2004 Jakub Jermar |
* All rights reserved. |
* |
* Redistribution and use in source and binary forms, with or without |
* modification, are permitted provided that the following conditions |
* are met: |
* |
* - Redistributions of source code must retain the above copyright |
* notice, this list of conditions and the following disclaimer. |
* - Redistributions in binary form must reproduce the above copyright |
* notice, this list of conditions and the following disclaimer in the |
* documentation and/or other materials provided with the distribution. |
* - The name of the author may not be used to endorse or promote products |
* derived from this software without specific prior written permission. |
* |
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
*/ |
|
/** @addtogroup sync |
* @{ |
*/ |
|
/** |
* @file |
* @brief Condition variables. |
*/ |
|
#include <synch/condvar.h> |
#include <synch/mutex.h> |
#include <synch/waitq.h> |
#include <synch/synch.h> |
#include <arch.h> |
|
/** Initialize condition variable. |
* |
* @param cv Condition variable. |
*/ |
void condvar_initialize(condvar_t *cv) |
{ |
waitq_initialize(&cv->wq); |
} |
|
/** |
* Signal the condition has become true |
* to the first waiting thread by waking it up. |
* |
* @param cv Condition variable. |
*/ |
void condvar_signal(condvar_t *cv) |
{ |
waitq_wakeup(&cv->wq, WAKEUP_FIRST); |
} |
|
/** |
* Signal the condition has become true |
* to all waiting threads by waking them up. |
* |
* @param cv Condition variable. |
*/ |
void condvar_broadcast(condvar_t *cv) |
{ |
waitq_wakeup(&cv->wq, WAKEUP_ALL); |
} |
|
/** Wait for the condition becoming true. |
* |
* @param cv Condition variable. |
* @param mtx Mutex. |
* @param usec Timeout value in microseconds. |
* @param flags Select mode of operation. |
* |
* For exact description of meaning of possible combinations |
* of usec and flags, see comment for waitq_sleep_timeout(). |
* Note that when SYNCH_FLAGS_NON_BLOCKING is specified here, |
* ESYNCH_WOULD_BLOCK is always returned. |
* |
* @return See comment for waitq_sleep_timeout(). |
*/ |
int _condvar_wait_timeout(condvar_t *cv, mutex_t *mtx, uint32_t usec, int flags) |
{ |
int rc; |
ipl_t ipl; |
|
ipl = waitq_sleep_prepare(&cv->wq); |
mutex_unlock(mtx); |
|
cv->wq.missed_wakeups = 0; /* Enforce blocking. */ |
rc = waitq_sleep_timeout_unsafe(&cv->wq, usec, flags); |
|
mutex_lock(mtx); |
waitq_sleep_finish(&cv->wq, rc, ipl); |
|
return rc; |
} |
|
/** @} |
*/ |