C++ MUTEX_ENTER函数代码示例

/**
 * start a thread pool.
 *
 * @param[in] pool  thread pool object
 *
 * @return operation status
 *    @retval 0 success
 *    @retval AFS_TP_ERROR thread create failure
 */
int
afs_tp_start(struct afs_thread_pool * pool)
{
    int code, ret = 0;
    struct afs_thread_pool_worker * worker;
    afs_uint32 i;

    MUTEX_ENTER(&pool->lock);
    if (pool->state != AFS_TP_STATE_INIT) {
        ret = AFS_TP_ERROR;
        goto done_sync;
    }
    pool->state = AFS_TP_STATE_STARTING;
    MUTEX_EXIT(&pool->lock);

    for (i = 0; i < pool->max_threads; i++) {
        code = _afs_tp_worker_start(pool, &worker);
        if (code) {
            ret = code;
        }
    }

    MUTEX_ENTER(&pool->lock);
    pool->state = AFS_TP_STATE_RUNNING;
done_sync:
    MUTEX_EXIT(&pool->lock);

    return ret;
}

/**
 * low-level thread entry point.
 *
 * @param[in] rock opaque pointer to thread worker object
 *
 * @return opaque return pointer from pool entry function
 *
 * @internal
 */
static void *
_afs_tp_worker_run(void * rock)
{
    struct afs_thread_pool_worker * worker = rock;
    struct afs_thread_pool * pool = worker->pool;

    /* register worker with pool */
    MUTEX_ENTER(&pool->lock);
    queue_Append(&pool->thread_list, worker);
    pool->nthreads++;
    MUTEX_EXIT(&pool->lock);

    /* call high-level entry point */
    worker->ret = (*pool->entry)(pool, worker, pool->work_queue, pool->rock);

    /* adjust pool live thread count */
    MUTEX_ENTER(&pool->lock);
    osi_Assert(pool->nthreads);
    queue_Remove(worker);
    pool->nthreads--;
    if (!pool->nthreads) {
        CV_BROADCAST(&pool->shutdown_cv);
        pool->state = AFS_TP_STATE_STOPPED;
    }
    MUTEX_EXIT(&pool->lock);

    _afs_tp_worker_free(worker);

    return NULL;
}

/*
 * thread to combine salvager child logs
 * back into the main salvageserver log
 */
static void *
SalvageLogCleanupThread(void * arg)
{
    struct log_cleanup_node * cleanup;

    MUTEX_ENTER(&worker_lock);

    while (1) {
	while (queue_IsEmpty(&log_cleanup_queue)) {
	    CV_WAIT(&log_cleanup_queue.queue_change_cv, &worker_lock);
	}

	while (queue_IsNotEmpty(&log_cleanup_queue)) {
	    cleanup = queue_First(&log_cleanup_queue, log_cleanup_node);
	    queue_Remove(cleanup);
	    MUTEX_EXIT(&worker_lock);
	    SalvageLogCleanup(cleanup->pid);
	    free(cleanup);
	    MUTEX_ENTER(&worker_lock);
	}
    }

    MUTEX_EXIT(&worker_lock);
    return NULL;
}

/**
 * lock a file on disk for the process.
 *
 * @param[in] lf       the struct VLockFile representing the file to lock
 * @param[in] offset   the offset in the file to lock
 * @param[in] locktype READ_LOCK or WRITE_LOCK
 * @param[in] nonblock 0 to wait for conflicting locks to clear before
 *                     obtaining the lock; 1 to fail immediately if a
 *                     conflicting lock is held by someone else
 *
 * @return operation status
 *  @retval 0 success
 *  @retval EBUSY someone else is holding a conflicting lock and nonblock=1 was
 *                specified
 *  @retval EIO   error acquiring file lock
 *
 * @note DAFS only
 *
 * @note do not try to lock/unlock the same offset in the same file from
 * different threads; use VGetDiskLock to protect threads from each other in
 * addition to other processes
 */
int
VLockFileLock(struct VLockFile *lf, afs_uint32 offset, int locktype, int nonblock)
{
    int code;

    osi_Assert(locktype == READ_LOCK || locktype == WRITE_LOCK);

    MUTEX_ENTER(&lf->mutex);

    if (lf->fd == INVALID_FD) {
	lf->fd = _VOpenPath(lf->path);
	if (lf->fd == INVALID_FD) {
	    MUTEX_EXIT(&lf->mutex);
	    return EIO;
	}
    }

    lf->refcount++;

    MUTEX_EXIT(&lf->mutex);

    code = _VLockFd(lf->fd, offset, locktype, nonblock);

    if (code) {
	MUTEX_ENTER(&lf->mutex);
	if (--lf->refcount < 1) {
	    _VCloseFd(lf->fd);
	    lf->fd = INVALID_FD;
	}
	MUTEX_EXIT(&lf->mutex);
    }

    return code;
}

void
OMR::Monitor::enter()
   {
#ifdef WIN32
   MUTEX_ENTER(_monitor);
#else
   int32_t rc = MUTEX_ENTER(_monitor);
   TR_ASSERT(rc == 0, "error locking monitor\n");
#endif
   }

void
OMR::Monitor::enter()
   {
#if defined(OMR_OS_WINDOWS)
   MUTEX_ENTER(_monitor);
#else
   int32_t rc = MUTEX_ENTER(_monitor);
   TR_ASSERT(rc == 0, "error locking monitor\n");
#endif /* defined(OMR_OS_WINDOWS) */
   }

static void *
SalvageChildReaperThread(void * args)
{
    int slot, pid, status;
    struct log_cleanup_node * cleanup;

    MUTEX_ENTER(&worker_lock);

    /* loop reaping our children */
    while (1) {
	/* wait() won't block unless we have children, so
	 * block on the cond var if we're childless */
	while (current_workers == 0) {
	    CV_WAIT(&worker_cv, &worker_lock);
	}

	MUTEX_EXIT(&worker_lock);

	cleanup = (struct log_cleanup_node *) malloc(sizeof(struct log_cleanup_node));

	while (Reap_Child("salvageserver", &pid, &status) < 0) {
	    /* try to prevent livelock if something goes wrong */
	    sleep(1);
	}

	VOL_LOCK;
	for (slot = 0; slot < Parallel; slot++) {
	    if (child_slot[slot] == pid)
		break;
	}
	osi_Assert(slot < Parallel);
	child_slot[slot] = 0;
	VOL_UNLOCK;

	SALVSYNC_doneWorkByPid(pid, status);

	MUTEX_ENTER(&worker_lock);

	if (cleanup) {
	    cleanup->pid = pid;
	    queue_Append(&log_cleanup_queue, cleanup);
	    CV_SIGNAL(&log_cleanup_queue.queue_change_cv);
	}

	/* ok, we've reaped a child */
	current_workers--;
	CV_BROADCAST(&worker_cv);
    }

    return NULL;
}

void valgrindFreeObject(MM_GCExtensionsBase *extensions, uintptr_t baseAddress)
{
    int objSize;
    if (MM_ForwardedHeader((omrobjectptr_t)baseAddress).isForwardedPointer())
    {
        /* In scavanger an object may act as pointer to another object(it's replica in another region).
           In this case, getConsumedSizeInBytesWithHeader returns some junk value.
           So instead we calculate the size of the object (replica) it is pointing to 
           and use it for freeing original object.
        */
        omrobjectptr_t fwObject = MM_ForwardedHeader((omrobjectptr_t)baseAddress).getForwardedObject();
        objSize = (int)((GC_ObjectModel)extensions->objectModel).getConsumedSizeInBytesWithHeader(fwObject);
    }
    else
    {
        objSize = (int)((GC_ObjectModel)extensions->objectModel).getConsumedSizeInBytesWithHeader((omrobjectptr_t)baseAddress);
    }

#if defined(VALGRIND_REQUEST_LOGS)
    VALGRIND_PRINTF_BACKTRACE("Clearing an object at 0x%lx of size %d\n", baseAddress, objSize);
#endif /* defined(VALGRIND_REQUEST_LOGS) */

    VALGRIND_CHECK_MEM_IS_DEFINED(baseAddress, objSize);
    VALGRIND_MEMPOOL_FREE(extensions->valgrindMempoolAddr, baseAddress);

    MUTEX_ENTER(extensions->memcheckHashTableMutex);
    hashTableRemove(extensions->memcheckHashTable, &baseAddress);
    MUTEX_EXIT(extensions->memcheckHashTableMutex);
}

/* Return the user's connection index of the most recently ready call; that is, a call that has received at least one reply packet */
int
multi_Select(struct multi_handle *mh)
{
    int index;
    SPLVAR;
    NETPRI;
#ifdef RX_ENABLE_LOCKS
    MUTEX_ENTER(&mh->lock);
#endif /* RX_ENABLE_LOCKS */
    while (mh->nextReady == mh->firstNotReady) {
	if (mh->nReady == mh->nConns) {
#ifdef RX_ENABLE_LOCKS
	    MUTEX_EXIT(&mh->lock);
#endif /* RX_ENABLE_LOCKS */
	    USERPRI;
	    return -1;
	}
#ifdef RX_ENABLE_LOCKS
	CV_WAIT(&mh->cv, &mh->lock);
#else /* RX_ENABLE_LOCKS */
	osi_rxSleep(mh);
#endif /* RX_ENABLE_LOCKS */
    }
    index = *(mh->nextReady);
    (mh->nextReady) += 1;
#ifdef RX_ENABLE_LOCKS
    MUTEX_EXIT(&mh->lock);
#endif /* RX_ENABLE_LOCKS */
    USERPRI;
    return index;
}

void _tdispInit(void) {
	MUTEX_INIT();

	MUTEX_ENTER();
	tdisp_lld_init();
	MUTEX_LEAVE();
}

void
hxge_hw_init_niu_common(p_hxge_t hxgep)
{
	p_hxge_hw_list_t hw_p;

	HXGE_DEBUG_MSG((hxgep, DDI_CTL, "==> hxge_hw_init_niu_common"));

	if ((hw_p = hxgep->hxge_hw_p) == NULL) {
		return;
	}

	MUTEX_ENTER(&hw_p->hxge_cfg_lock);
	if (hw_p->flags & COMMON_INIT_DONE) {
		HXGE_DEBUG_MSG((hxgep, MOD_CTL, "hxge_hw_init_niu_common"
		    " already done for dip $%p exiting", hw_p->parent_devp));
		MUTEX_EXIT(&hw_p->hxge_cfg_lock);
		return;
	}

	hw_p->flags = COMMON_INIT_START;
	HXGE_DEBUG_MSG((hxgep, MOD_CTL,
	    "hxge_hw_init_niu_common Started for device id %x",
	    hw_p->parent_devp));

	(void) hxge_pfc_hw_reset(hxgep);
	hw_p->flags = COMMON_INIT_DONE;
	MUTEX_EXIT(&hw_p->hxge_cfg_lock);

	HXGE_DEBUG_MSG((hxgep, MOD_CTL,
	    "hxge_hw_init_niu_common Done for device id %x",
	    hw_p->parent_devp));
	HXGE_DEBUG_MSG((hxgep, DDI_CTL, "<== hxge_hw_init_niu_common"));
}

afs_int32
canWrite(int fid)
{
#ifndef AFS_PTHREAD_ENV
    afs_int32 code = 0;
#endif
    extern dumpSyncP dumpSyncPtr;

    ObtainWriteLock(&dumpSyncPtr->ds_lock);

    /* let the pipe drain */
    while (dumpSyncPtr->ds_bytes > 0) {
	if (dumpSyncPtr->ds_readerStatus == DS_WAITING) {
	    dumpSyncPtr->ds_readerStatus = 0;
#ifdef AFS_PTHREAD_ENV
	    CV_BROADCAST(&dumpSyncPtr->ds_readerStatus_cond);
#else
	    code = LWP_SignalProcess(&dumpSyncPtr->ds_readerStatus);
	    if (code)
		LogError(code, "canWrite: Signal delivery failed\n");
#endif
	}
	dumpSyncPtr->ds_writerStatus = DS_WAITING;
	ReleaseWriteLock(&dumpSyncPtr->ds_lock);
#ifdef AFS_PTHREAD_ENV
	MUTEX_ENTER(&dumpSyncPtr->ds_writerStatus_mutex);
	CV_WAIT(&dumpSyncPtr->ds_writerStatus_cond, &dumpSyncPtr->ds_writerStatus_mutex);
	MUTEX_EXIT(&dumpSyncPtr->ds_writerStatus_mutex);
#else
	LWP_WaitProcess(&dumpSyncPtr->ds_writerStatus);
#endif
	ObtainWriteLock(&dumpSyncPtr->ds_lock);
    }
    return (1);
}

void
afs_cv_timedwait(afs_kcondvar_t * cv, afs_kmutex_t * l, int waittime)
{
    int seq, isAFSGlocked = ISAFS_GLOCK();
    long t = waittime * HZ / 1000;
#ifdef DECLARE_WAITQUEUE
    DECLARE_WAITQUEUE(wait, current);
#else
    struct wait_queue wait = { current, NULL };
#endif
    seq = cv->seq;

    set_current_state(TASK_INTERRUPTIBLE);
    add_wait_queue(&cv->waitq, &wait);

    if (isAFSGlocked)
	AFS_GUNLOCK();
    MUTEX_EXIT(l);

    while(seq == cv->seq) {
	t = schedule_timeout(t);
	if (!t)         /* timeout */
	    break;
    }
    
    remove_wait_queue(&cv->waitq, &wait);
    set_current_state(TASK_RUNNING);

    if (isAFSGlocked)
	AFS_GLOCK();
    MUTEX_ENTER(l);
}

void tdispSetBacklight(uint16_t percentage) {
	if (percentage > 100)
	  percentage = 100;
	MUTEX_ENTER();
	tdisp_lld_set_backlight(percentage);
	MUTEX_LEAVE();
}

void valgrindClearRange(MM_GCExtensionsBase *extensions, uintptr_t baseAddress, uintptr_t size)
{
    if (size == 0)
    {
        return;
    }
    uintptr_t topInclusiveAddr = baseAddress + size - 1;

#if defined(VALGRIND_REQUEST_LOGS)
    VALGRIND_PRINTF_BACKTRACE("Clearing objects in range b/w 0x%lx and  0x%lx\n", baseAddress, topInclusiveAddr);
#endif /* defined(VALGRIND_REQUEST_LOGS) */

    MUTEX_ENTER(extensions->memcheckHashTableMutex);
    GC_HashTableIterator it(extensions->memcheckHashTable);
    uintptr_t *currentSlotPointer = (uintptr_t *)it.nextSlot();
    while (currentSlotPointer != NULL)
    {
        if (baseAddress <= *currentSlotPointer && topInclusiveAddr >= *currentSlotPointer)
        {
            valgrindFreeObjectDirect(extensions, *currentSlotPointer);
            it.removeSlot();
        }
        currentSlotPointer = (uintptr_t *)it.nextSlot();
    }
    MUTEX_EXIT(extensions->memcheckHashTableMutex);

    /* Valgrind automatically marks free objects as noaccess.
    We still mark the entire region as no access for any left out areas */
    valgrindMakeMemNoaccess(baseAddress, size);
}