Speed up Thread.ManagedThreadId.

[mono.git] / mcs / class / corlib / System.Threading / SemaphoreSlim.cs

diff --git a/mcs/class/corlib/System.Threading/SemaphoreSlim.cs b/mcs/class/corlib/System.Threading/SemaphoreSlim.cs
index dc730f96aaa26da4c0d23861e89c14752c3e0b64..340d95057c0ac3dbafb394b3c3020018095ae6a0 100644 (file)
--- a/mcs/class/corlib/System.Threading/SemaphoreSlim.cs
+++ b/mcs/class/corlib/System.Threading/SemaphoreSlim.cs
@@ -30,11 +30,14 @@ namespace System.Threading
 {
        public class SemaphoreSlim : IDisposable
        {
+               const int spinCount = 10;
+               const int deepSleepTime = 20;
+
                readonly int max;
                int currCount;
                bool isDisposed;
 
-               ManualResetEvent handle;
+               EventWaitHandle handle;
 
                public SemaphoreSlim (int initial) : this (initial, int.MaxValue)
                {
@@ -96,7 +99,7 @@ namespace System.Threading
                                newValue = newValue > max ? max : newValue;
                        } while (Interlocked.CompareExchange (ref currCount, newValue, oldValue) != oldValue);
 
-                       handle.Reset ();
+                       handle.Set ();
 
                        return oldValue;
                }
@@ -136,14 +139,14 @@ namespace System.Threading
 
                        Watch sw = Watch.StartNew ();
 
-                       Func<bool> stopCondition =
-                               () => token.IsCancellationRequested || (millisecondsTimeout >= 0 && sw.ElapsedMilliseconds > millisecondsTimeout);
+                       Func<bool> stopCondition = () => millisecondsTimeout >= 0 && sw.ElapsedMilliseconds > millisecondsTimeout;
 
                        do {
                                bool shouldWait;
                                int result;
 
                                do {
+                                       token.ThrowIfCancellationRequested ();
                                        if (stopCondition ())
                                                return false;
 
@@ -158,17 +161,21 @@ namespace System.Threading
 
                                if (!shouldWait) {
                                        if (result == 1)
-                                               handle.Set ();
+                                               handle.Reset ();
                                        break;
                                }
 
                                SpinWait wait = new SpinWait ();
 
                                while (Thread.VolatileRead (ref currCount) <= 0) {
+                                       token.ThrowIfCancellationRequested ();
                                        if (stopCondition ())
                                                return false;
 
-                                       wait.SpinOnce ();
+                                       if (wait.Count > spinCount)
+                                               handle.WaitOne (Math.Min (Math.Max (millisecondsTimeout - (int)sw.ElapsedMilliseconds, 1), deepSleepTime));
+                                       else
+                                               wait.SpinOnce ();
                                }
                        } while (true);