Handle early wakeup of counter loop (#57170)

* Fix #56695 * prevent a negative delta value * PR feedback + bug fix * bug fix is preexisting: if a user other than the one who is listening sets the interval to 0 while the counter is enabled, it makes the counter continuously submit values. Changed this so that an interval value of <= 0 results in the counter being disabled * Add assert after offline conversation
dotnet · Aug 13, 2021 · 3042bd7 · 3042bd7
1 parent afbb7df
commit 3042bd7
Showing 1 changed file with 4 additions and 2 deletions.
diff --git a/src/libraries/System.Private.CoreLib/src/System/Diagnostics/Tracing/CounterGroup.cs b/src/libraries/System.Private.CoreLib/src/System/Diagnostics/Tracing/CounterGroup.cs
@@ -127,7 +127,7 @@ private void EnableTimer(float pollingIntervalInSeconds)
             Debug.Assert(Monitor.IsEntered(s_counterGroupLock));
             if (pollingIntervalInSeconds <= 0)
             {
-                _pollingIntervalInMilliseconds = 0;
+                DisableTimer();
             }
             else if (_pollingIntervalInMilliseconds == 0 || pollingIntervalInSeconds * 1000 < _pollingIntervalInMilliseconds)
             {
@@ -187,6 +187,7 @@ private void EnableTimer(float pollingIntervalInSeconds)
 
         private void DisableTimer()
         {
+            Debug.Assert(Monitor.IsEntered(s_counterGroupLock));
             _pollingIntervalInMilliseconds = 0;
             s_counterGroupEnabledList?.Remove(this);
         }
@@ -252,7 +253,8 @@ private void OnTimer()
                 {
                     _timeStampSinceCollectionStarted = now;
                     TimeSpan delta = now - _nextPollingTimeStamp;
-                    if (delta > TimeSpan.Zero && _pollingIntervalInMilliseconds > 0)
+                    delta = _pollingIntervalInMilliseconds > delta.TotalMilliseconds ? TimeSpan.FromMilliseconds(_pollingIntervalInMilliseconds) : delta;
+                    if (_pollingIntervalInMilliseconds > 0)
                         _nextPollingTimeStamp += TimeSpan.FromMilliseconds(_pollingIntervalInMilliseconds * Math.Ceiling(delta.TotalMilliseconds / _pollingIntervalInMilliseconds));
                 }
             }