/// <summary>
/// Acquires a reader lock.
/// </summary>
/// <returns>An object (considered opaque by client code) that should be disposed
/// once the lock is not needed.</returns>
/// <remarks>It is strongly recommended to use the <b>using</b> construct with
/// this method.</remarks>
public Cookie AcquireReadLock()
{
if (this.@lock == null)
{
return(new Cookie(CookieAction.None, null, null));
}
CookieAction action;
if ([email protected] && [email protected] && [email protected])
{
action = CookieAction.ExitReadLock;
DeadlockMonitor.EnterWaiting(@lock, writeLock, lockedObject);
if ([email protected](WarningTimeout))
{
Debug.Print("Acquiring a read lock on {0} from thread {1} ({2}) is taking longer than expected.",
lockedObject, Thread.CurrentThread.ManagedThreadId, Thread.CurrentThread.Name);
DeadlockMonitor.DetectDeadlocks();
@lock.EnterReadLock();
}
DeadlockMonitor.ExitWaiting(@lock, writeLock);
DeadlockMonitor.EnterAcquired(@lock, readLock, lockedObject);
}
else
{
action = CookieAction.None;
}
return(new Cookie(action, this, GetStackTrace()));
}
/// <inheritdoc />
public void Dispose()
{
switch (this.action)
{
case CookieAction.None:
break;
case CookieAction.ExitReadLock:
[email protected]();
DeadlockMonitor.ExitAcquired(this.parent.@lock, readLock);
break;
case CookieAction.ExitWriteLock:
[email protected]();
DeadlockMonitor.ExitAcquired(this.parent.@lock, writeLock);
break;
case CookieAction.ExitWriteAndUpgradeableReadLock:
[email protected]();
[email protected]();
DeadlockMonitor.ExitAcquired(this.parent.@lock, writeLock);
DeadlockMonitor.ExitAcquired(this.parent.@lock, upgradableReadLock);
break;
case CookieAction.EnterWriteLock:
DeadlockMonitor.EnterWaiting(this.parent.@lock, readLock, this.parent.lockedObject);
DeadlockMonitor.EnterWaiting(this.parent.@lock, writeLock, this.parent.lockedObject);
DeadlockMonitor.EnterWaiting(this.parent.@lock, upgradableReadLock, this.parent.lockedObject);
if ([email protected](WarningTimeout))
{
Debug.Print("Reacquiring a write lock on {0} from thread {1} ({2}) is taking longer than expected.",
this.parent.lockedObject, Thread.CurrentThread.ManagedThreadId, Thread.CurrentThread.Name);
DeadlockMonitor.DetectDeadlocks();
[email protected]();
}
DeadlockMonitor.ConvertWaitingToAcquired(this.parent.@lock, writeLock, this.parent.lockedObject);
DeadlockMonitor.ExitWaiting(this.parent.@lock, readLock);
DeadlockMonitor.ExitWaiting(this.parent.@lock, upgradableReadLock);
break;
case CookieAction.ExitUpgrableReaderLock:
[email protected]();
DeadlockMonitor.ExitAcquired(this.parent.@lock, upgradableReadLock);
break;
}
this.action = CookieAction.None;
GC.SuppressFinalize(this);
}
/// <summary>
/// Handler executed before execution of the method to which the current custom attribute is applied.
/// </summary>
/// <param name="eventArgs"></param>
public override void OnEntry(MethodExecutionArgs eventArgs)
{
object o = eventArgs.Instance ?? eventArgs.Method.DeclaringType;
DeadlockMonitor.EnterWaiting(o, null, null);
if (!Monitor.TryEnter(o, 200))
{
DeadlockMonitor.DetectDeadlocks();
Monitor.Enter(o);
}
DeadlockMonitor.ConvertWaitingToAcquired(o, null, null);
}
private static void DetectProblems(int i)
{
if (i % DeadlockDetectionPeriod / WarningTimeout == 0)
{
DeadlockMonitor.DetectDeadlocks();
}
// Doing a GC will collect eventual ghost locks.
if (i % GarbageCollectionDetectionPeriod / WarningTimeout == 0)
{
GC.Collect();
}
}
/// <summary>
/// Acquires an observer lock.
/// </summary>
/// <returns>An object (considered opaque by client code) that should be disposed
/// once the lock is not needed.</returns>
/// <remarks>It is strongly recommended to use the <b>using</b> construct with
/// this method.</remarks>
public Cookie AcquireObserverLock()
{
if (this.@lock == null)
{
return(new Cookie(CookieAction.None, null, null));
}
if ([email protected])
{
[email protected]();
DeadlockMonitor.ExitAcquired(this.@lock, writeLock);
return(new Cookie(CookieAction.EnterWriteLock, this, GetStackTrace()));
}
else
{
return(new Cookie(CookieAction.None, this, GetStackTrace()));
}
}
/// <summary>
/// Acquires an upgradable reader lock.
/// </summary>
/// <returns>An object (considered opaque by client code) that should be disposed
/// once the lock is not needed.</returns>
/// <remarks>It is strongly recommended to use the <b>using</b> construct with
/// this method.</remarks>
public Cookie AcquireUpgradableReadLock()
{
if (this.@lock == null)
{
return(new Cookie(CookieAction.None, null, null));
}
CookieAction action;
if ([email protected] && [email protected])
{
if (@lock.IsReadLockHeld)
{
throw new InvalidOperationException(
string.Format("Cannot acquire a write lock on {{{0}}}, because the current thread " +
"already holds a read lock on that object, and acquiring a write lock may cause a deadlock.",
@lock));
}
action = CookieAction.ExitUpgrableReaderLock;
DeadlockMonitor.EnterWaiting(@lock, upgradableReadLock, lockedObject);
DeadlockMonitor.EnterWaiting(@lock, writeLock, lockedObject);
if ([email protected](WarningTimeout))
{
Debug.Print("Acquiring a read lock on {0} from thread {1} ({2}) is taking longer than expected.",
lockedObject, Thread.CurrentThread.ManagedThreadId, Thread.CurrentThread.Name);
DeadlockMonitor.DetectDeadlocks();
@lock.EnterUpgradeableReadLock();
}
DeadlockMonitor.ConvertWaitingToAcquired(@lock, upgradableReadLock, lockedObject);
DeadlockMonitor.ExitWaiting(@lock, writeLock);
}
else
{
action = CookieAction.None;
}
return(new Cookie(action, this, GetStackTrace()));
}
