public void Lock()
{
int myCluster = ThreadID.GetCluster();
Backoff localBackoff =
new Backoff(LOCAL_MIN_DELAY, LOCAL_MAX_DELAY);
Backoff remoteBackoff =
new Backoff(REMOTE_MIN_DELAY, REMOTE_MAX_DELAY);
while (true)
{
if (Interlocked.CompareExchange(ref state, myCluster, FREE) == FREE)
{
return;
}
int lockState = state;
if (lockState == myCluster)
{
localBackoff.DoBackoff();
}
else
{
remoteBackoff.DoBackoff();
}
}
}
public void NodeUnlock()
{
int oldState = 0;
int newState = (int)ThreadID.GetCluster();
// successorMustWait = true;
newState |= SMW_MASK;
// tailWhenSpliced = false;
newState &= (~TWS_MASK);
do
{
oldState = state;
} while (Interlocked.CompareExchange(ref state, oldState, newState) != oldState);
}
public void Lock()
{
QNode myNode = currNode.Value;
QNode localQueue = localQueues[ThreadID.GetCluster()];
// splice my QNode into local queue
QNode myPred = null;
do
{
myPred = localQueue;
} while (Interlocked.CompareExchange(ref localQueue, myPred, myNode) != myNode);
if (myPred != null)
{
bool iOwnLock = myPred.WaitForGrantOrClusterMaster();
if (iOwnLock)
{
predNode.Value = myPred;
return;
}
}
// I am the cluster master: splice local queue into global queue.
QNode localTail = null;
do
{
myPred = globalQueue;
localTail = localQueue;
} while (Interlocked.CompareExchange(ref globalQueue, myPred, localTail) != localTail);
// inform successor it is the new master
localTail.TailWhenSpliced = true;
while (myPred.SuccessorMustWait)
{
}
;
predNode.Value = myPred;
return;
}
