Clean up IThreadPool interface (#1696)

- Remove tcs completion methods

src/Microsoft.AspNetCore.Server.Kestrel.Core/Internal/Infrastructure/IThreadPool.cs

@@ -3,16 +3,12 @@
 
 using System;
 using System.Threading;
-using System.Threading.Tasks;
 using Microsoft.AspNetCore.Server.Kestrel.Internal.System.IO.Pipelines;
 
 namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Infrastructure
 {
     public interface IThreadPool : IScheduler
     {
-        void Complete(TaskCompletionSource<object> tcs);
-        void Cancel(TaskCompletionSource<object> tcs);
-        void Error(TaskCompletionSource<object> tcs, Exception ex);
         void Run(Action action);
         void UnsafeRun(WaitCallback action, object state);
     }

src/Microsoft.AspNetCore.Server.Kestrel.Core/Internal/Infrastructure/InlineLoggingThreadPool.cs

@@ -3,7 +3,6 @@
 
 using System;
 using System.Threading;
-using System.Threading.Tasks;
 using Microsoft.Extensions.Logging;
 
 namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Infrastructure
@@ -29,42 +28,6 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Infrastructure
             }
         }
 
-        public void Complete(TaskCompletionSource<object> tcs)
-        {
-            try
-            {
-                tcs.TrySetResult(null);
-            }
-            catch (Exception e)
-            {
-                _log.LogError(0, e, "InlineLoggingThreadPool.Complete");
-            }
-        }
-
-        public void Cancel(TaskCompletionSource<object> tcs)
-        {
-            try
-            {
-                tcs.TrySetCanceled();
-            }
-            catch (Exception e)
-            {
-                _log.LogError(0, e, "InlineLoggingThreadPool.Cancel");
-            }
-        }
-
-        public void Error(TaskCompletionSource<object> tcs, Exception ex)
-        {
-            try
-            {
-                tcs.TrySetException(ex);
-            }
-            catch (Exception e)
-            {
-                _log.LogError(0, e, "InlineLoggingThreadPool.Error");
-            }
-        }
-
         public void UnsafeRun(WaitCallback action, object state)
         {
             action(state);

src/Microsoft.AspNetCore.Server.Kestrel.Core/Internal/Infrastructure/LoggingThreadPool.cs

@@ -3,7 +3,6 @@
 
 using System;
 using System.Threading;
-using System.Threading.Tasks;
 using Microsoft.Extensions.Logging;
 
 namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Infrastructure
@@ -13,8 +12,6 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Infrastructure
         private readonly IKestrelTrace _log;
 
         private WaitCallback _runAction;
-        private WaitCallback _cancelTcs;
-        private WaitCallback _completeTcs;
 
         public LoggingThreadPool(IKestrelTrace log)
         {
@@ -25,8 +22,6 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Infrastructure
             // call stack for exceptions and profiling else it shows up as LoggingThreadPool.ctor>b__4_0
             // and you aren't sure which of the 3 functions was called.
             RunAction();
-            CompleteTcs();
-            CancelTcs();
         }
 
         private void RunAction()
@@ -45,38 +40,6 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Infrastructure
             };
         }
 
-        private void CompleteTcs()
-        {
-            // Capture _log in a singleton closure
-            _completeTcs = (o) =>
-            {
-                try
-                {
-                    ((TaskCompletionSource<object>)o).TrySetResult(null);
-                }
-                catch (Exception e)
-                {
-                    _log.LogError(0, e, "LoggingThreadPool.Complete");
-                }
-            };
-        }
-
-        private void CancelTcs()
-        {
-            // Capture _log in a singleton closure
-            _cancelTcs = (o) =>
-            {
-                try
-                {
-                    ((TaskCompletionSource<object>)o).TrySetCanceled();
-                }
-                catch (Exception e)
-                {
-                    _log.LogError(0, e, "LoggingThreadPool.Cancel");
-                }
-            };
-        }
-
         public void Run(Action action)
         {
             ThreadPool.QueueUserWorkItem(_runAction, action);
@@ -87,32 +50,6 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Infrastructure
             ThreadPool.QueueUserWorkItem(action, state);
         }
 
-        public void Complete(TaskCompletionSource<object> tcs)
-        {
-            ThreadPool.QueueUserWorkItem(_completeTcs, tcs);
-        }
-
-        public void Cancel(TaskCompletionSource<object> tcs)
-        {
-            ThreadPool.QueueUserWorkItem(_cancelTcs, tcs);
-        }
-
-        public void Error(TaskCompletionSource<object> tcs, Exception ex)
-        {
-            // ex and _log are closure captured 
-            ThreadPool.QueueUserWorkItem((o) =>
-            {
-                try
-                {
-                    ((TaskCompletionSource<object>)o).TrySetException(ex);
-                }
-                catch (Exception e)
-                {
-                    _log.LogError(0, e, "LoggingThreadPool.Error");
-                }
-            }, tcs);
-        }
-
         public void Schedule(Action action)
         {
             Run(action);

test/Microsoft.AspNetCore.Server.Kestrel.Core.Tests/LoggingThreadPoolTests.cs

@@ -1,48 +0,0 @@
-// Copyright (c) .NET Foundation. All rights reserved.
-// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
-
-
-using System;
-using System.Threading.Tasks;
-using Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Infrastructure;
-using Microsoft.AspNetCore.Testing;
-using Xunit;
-
-namespace Microsoft.AspNetCore.Server.Kestrel.Core.Tests
-{
-    public class LoggingThreadPoolTests
-    {
-        [Fact]
-        public void TcsContinuationErrorsDontGetLoggedAsGeneralErrors()
-        {
-            var testLogger = new TestApplicationErrorLogger();
-            var testKestrelTrace = new TestKestrelTrace(testLogger);
-            var threadPool = new LoggingThreadPool(testKestrelTrace);
-
-            var completeTcs = new TaskCompletionSource<object>();
-            ThrowSynchronously(completeTcs.Task);
-            threadPool.Complete(completeTcs);
-
-            var errorTcs = new TaskCompletionSource<object>();
-            ThrowSynchronously(errorTcs.Task);
-            threadPool.Error(errorTcs, new Exception());
-
-            var cancelTcs = new TaskCompletionSource<object>();
-            ThrowSynchronously(cancelTcs.Task);
-            threadPool.Cancel(cancelTcs);
-
-            Assert.Throws<AggregateException>(() =>
-                Task.WhenAll(completeTcs.Task, errorTcs.Task, cancelTcs.Task).Wait());
-
-            Assert.Equal(0, testLogger.TotalErrorsLogged);
-        }
-
-        private void ThrowSynchronously(Task task)
-        {
-            task.ContinueWith(_ =>
-            {
-                throw new Exception();
-            }, TaskContinuationOptions.ExecuteSynchronously);
-        }
-    }
-}