Skip to content

[Diagnostics]: High-performance EventSource runtime async profiler. #127238

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
lateralusX wants to merge 20 commits into
base: main
Choose a base branch
from
Open

[Diagnostics]: High-performance EventSource runtime async profiler. #127238

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
20 commits
Select commit Hold shift + click to select a range
8b0a6de
High-performance async method profiling over EventSource.
lateralusX Apr 2, 2026
c78aebf
Additional adjustments:
lateralusX Apr 21, 2026
e06efd3
Fix line ending.
lateralusX Apr 21, 2026
69a54fd
Fix Mono build.
lateralusX Apr 21, 2026
ebe8c1c
Review feedback.
lateralusX Apr 22, 2026
da09376
Refactor debugger flags and way to trigger it.
lateralusX Apr 23, 2026
31dcc36
Fix failing tests on CI.
lateralusX Apr 23, 2026
e707a2b
Make async profiler CoreCLR specific for now.
lateralusX Apr 23, 2026
4d72842
Add periodic sync clock event + clock sync logic.
lateralusX Apr 23, 2026
654d38b
Simplify the update of instrumentation flags + drop use of AsyncDebug…
lateralusX Apr 23, 2026
00f01a8
Review feedback.
lateralusX Apr 23, 2026
ebf4173
Harden order sensetive tests.
lateralusX Apr 23, 2026
512771f
Review feedback.
lateralusX Apr 24, 2026
dc898b7
Review feedback.
lateralusX Apr 24, 2026
b16595d
Reduce Unsafe code in Serializer.
lateralusX Apr 27, 2026
3cd49a2
Let source generator create GUID.
lateralusX Apr 27, 2026
934fb2e
Added better rollback support for async header.
lateralusX Apr 27, 2026
dc65f74
Changes after rebase.
lateralusX Apr 28, 2026
e06b524
Span some more.
lateralusX Apr 28, 2026
8353942
Add description to continuation wrapper.
lateralusX Apr 28, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
1 change: 1 addition & 0 deletions src/coreclr/System.Private.CoreLib/System.Private.CoreLib.csproj
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -206,6 +206,7 @@
<Compile Include="$(BclSourcesRoot)\System\Runtime\CompilerServices\GenericsHelpers.cs" />
<Compile Include="$(BclSourcesRoot)\System\Runtime\CompilerServices\InitHelpers.cs" />
<Compile Include="$(BclSourcesRoot)\System\Runtime\CompilerServices\AsyncHelpers.CoreCLR.cs" />
<Compile Include="$(BclSourcesRoot)\System\Runtime\CompilerServices\AsyncProfiler.CoreCLR.cs" />
<Compile Include="$(BclSourcesRoot)\System\Runtime\CompilerServices\RuntimeHelpers.CoreCLR.cs" />
<Compile Include="$(BclSourcesRoot)\System\Runtime\CompilerServices\StaticsHelpers.cs" />
<Compile Include="$(BclSourcesRoot)\System\Runtime\CompilerServices\VirtualDispatchHelpers.cs" />
Expand Down
109 changes: 98 additions & 11 deletions ...oreclr/System.Private.CoreLib/src/System/Runtime/CompilerServices/AsyncHelpers.CoreCLR.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -139,6 +139,13 @@ internal unsafe ref struct AsyncDispatcherInfo
// to match an inflight Task to the corresponding Continuation chain.
public Task? CurrentTask;

#if TARGET_64BIT
[FieldOffset(24)]
#else
[FieldOffset(12)]
#endif
public AsyncProfiler.Info AsyncProfilerInfo;

// Information about current task dispatching, to be used for async
// stackwalking.
[ThreadStatic]
Expand Down Expand Up @@ -498,7 +505,7 @@ internal void InstrumentedHandleSuspended(AsyncInstrumentation.Flags flags, ref
{
if (AsyncInstrumentation.IsEnabled.AsyncDebugger(flags))
{
Continuation? nextContinuation = t_runtimeAsyncAwaitState.SentinelContinuation!.Next;
Continuation? nextContinuation = state.SentinelContinuation!.Next;

AsyncDebugger.HandleSuspended(nextContinuation, newContinuation);

Expand Down Expand Up @@ -659,20 +666,21 @@ private unsafe void InstrumentedDispatchContinuations(AsyncInstrumentation.Flags
ref byte resultLoc = ref nextContinuation != null ? ref nextContinuation.GetResultStorageOrNull() : ref GetResultStorage();

RuntimeAsyncInstrumentationHelpers.ResumeRuntimeAsyncMethod(ref asyncDispatcherInfo, flags, curContinuation);
Continuation? newContinuation = curContinuation.ResumeInfo->Resume(curContinuation, ref resultLoc);
Continuation? newContinuation = RuntimeAsyncInstrumentationHelpers.ResumeContinuation(ref asyncDispatcherInfo, flags, curContinuation, ref resultLoc);

if (newContinuation != null)
{
newContinuation.Next = nextContinuation;
RuntimeAsyncInstrumentationHelpers.SuspendRuntimeAsyncContext(flags, curContinuation, newContinuation);

RuntimeAsyncInstrumentationHelpers.AwaitSuspendedRuntimeAsyncContext(ref asyncDispatcherInfo, flags, curContinuation, newContinuation, awaitState.SentinelContinuation!.Next);
InstrumentedHandleSuspended(flags, ref awaitState, newContinuation);

awaitState.Pop();
refDispatcherInfo = asyncDispatcherInfo.Next;
return;
}

RuntimeAsyncInstrumentationHelpers.CompleteRuntimeAsyncMethod(flags, curContinuation);
RuntimeAsyncInstrumentationHelpers.CompleteRuntimeAsyncMethod(ref asyncDispatcherInfo, flags, curContinuation);
}
catch (Exception ex)
{
Expand All @@ -698,7 +706,7 @@ private unsafe void InstrumentedDispatchContinuations(AsyncInstrumentation.Flags
return;
}

RuntimeAsyncInstrumentationHelpers.UnwindRuntimeAsyncMethodHandledException(flags, curContinuation, unwindedFrames);
RuntimeAsyncInstrumentationHelpers.UnwindRuntimeAsyncMethodHandledException(ref asyncDispatcherInfo, flags, curContinuation, unwindedFrames);

handlerContinuation.SetException(ex);
asyncDispatcherInfo.NextContinuation = handlerContinuation;
Expand All @@ -723,7 +731,7 @@ private unsafe void InstrumentedDispatchContinuations(AsyncInstrumentation.Flags

if (QueueContinuationFollowUpActionIfNecessary(asyncDispatcherInfo.NextContinuation))
{
RuntimeAsyncInstrumentationHelpers.SuspendRuntimeAsyncContext(ref asyncDispatcherInfo, flags, curContinuation);
RuntimeAsyncInstrumentationHelpers.QueueSuspendedRuntimeAsyncContext(ref asyncDispatcherInfo, flags, curContinuation, asyncDispatcherInfo.NextContinuation);

awaitState.Pop();
refDispatcherInfo = asyncDispatcherInfo.Next;
Expand Down Expand Up @@ -837,6 +845,15 @@ private static void InstrumentedFinalizeRuntimeAsyncTask<T>(RuntimeAsyncTask<T>
{
if (AsyncInstrumentation.IsEnabled.CreateAsyncContext(flags))
{
if (AsyncInstrumentation.IsEnabled.AsyncProfiler(flags))
{
Continuation? nextContinuation = state.SentinelContinuation!.Next;
if (nextContinuation != null)
{
AsyncProfiler.CreateAsyncContext.Create((ulong)task.Id, nextContinuation);
}
}

if (AsyncInstrumentation.IsEnabled.AsyncDebugger(flags))
{
task.NotifyDebuggerOfRuntimeAsyncState();
Expand Down Expand Up @@ -1053,9 +1070,15 @@ public static bool InstrumentCheckPoint
public static void ResumeRuntimeAsyncContext(Task task, ref AsyncDispatcherInfo info, AsyncInstrumentation.Flags flags)
{
info.CurrentTask = task;
AsyncProfiler.InitInfo(ref info.AsyncProfilerInfo);

if (AsyncInstrumentation.IsEnabled.ResumeAsyncContext(flags))
{
if (AsyncInstrumentation.IsEnabled.AsyncProfiler(flags))
{
AsyncProfiler.ResumeAsyncContext.Resume(ref info);
}

if (AsyncInstrumentation.IsEnabled.AsyncDebugger(flags))
{
AsyncDebugger.ResumeAsyncContext(task.Id);
Expand All @@ -1064,10 +1087,15 @@ public static void ResumeRuntimeAsyncContext(Task task, ref AsyncDispatcherInfo
}

[MethodImpl(MethodImplOptions.AggressiveInlining)]
public static void SuspendRuntimeAsyncContext(ref AsyncDispatcherInfo info, AsyncInstrumentation.Flags flags, Continuation curContinuation)
public static void QueueSuspendedRuntimeAsyncContext(ref AsyncDispatcherInfo info, AsyncInstrumentation.Flags flags, Continuation curContinuation, Continuation nextContinuation)
{
if (AsyncInstrumentation.IsEnabled.SuspendAsyncContext(flags))
{
if (AsyncInstrumentation.IsEnabled.AsyncProfiler(flags))
{
AsyncProfiler.SuspendAsyncContext.Suspend(ref info, nextContinuation);
}

if (AsyncInstrumentation.IsEnabled.AsyncDebugger(flags))
{
AsyncDebugger.SuspendAsyncContext(ref info, curContinuation);
Expand All @@ -1076,10 +1104,15 @@ public static void SuspendRuntimeAsyncContext(ref AsyncDispatcherInfo info, Asyn
}

[MethodImpl(MethodImplOptions.AggressiveInlining)]
public static void SuspendRuntimeAsyncContext(AsyncInstrumentation.Flags flags, Continuation curContinuation, Continuation newContinuation)
public static void AwaitSuspendedRuntimeAsyncContext(ref AsyncDispatcherInfo info, AsyncInstrumentation.Flags flags, Continuation curContinuation, Continuation newContinuation, Continuation? nextContinuation)
{
if (AsyncInstrumentation.IsEnabled.SuspendAsyncContext(flags))
{
if (AsyncInstrumentation.IsEnabled.AsyncProfiler(flags))
{
AsyncProfiler.SuspendAsyncContext.Suspend(ref info, nextContinuation ?? newContinuation);
}

if (AsyncInstrumentation.IsEnabled.AsyncDebugger(flags))
{
AsyncDebugger.SuspendAsyncContext(curContinuation, newContinuation);
Expand All @@ -1092,28 +1125,53 @@ public static void CompleteRuntimeAsyncContext(ref AsyncDispatcherInfo info, Asy
{
if (AsyncInstrumentation.IsEnabled.CompleteAsyncContext(flags))
{
if (AsyncInstrumentation.IsEnabled.AsyncProfiler(flags))
{
AsyncProfiler.CompleteAsyncContext.Complete(ref info.AsyncProfilerInfo);
}

if (AsyncInstrumentation.IsEnabled.AsyncDebugger(flags))
{
AsyncDebugger.CompleteAsyncContext(info.CurrentTask);
}
}
}

public static void UnwindRuntimeAsyncMethodUnhandledException(ref AsyncDispatcherInfo info, AsyncInstrumentation.Flags flags, Exception ex, Continuation curContinuation, uint _)
public static void UnwindRuntimeAsyncMethodUnhandledException(ref AsyncDispatcherInfo info, AsyncInstrumentation.Flags flags, Exception ex, Continuation curContinuation, uint unwindedFrames)
{
if (AsyncInstrumentation.IsEnabled.AsyncProfiler(flags))
{
AsyncProfiler.ContinuationWrapper.UnwindIndex(ref info.AsyncProfilerInfo, unwindedFrames);
}

if (AsyncInstrumentation.IsEnabled.UnwindAsyncException(flags))
{
if (AsyncInstrumentation.IsEnabled.AsyncProfiler(flags))
{
AsyncProfiler.AsyncMethodException.Unhandled(ref info.AsyncProfilerInfo, unwindedFrames);
}

if (AsyncInstrumentation.IsEnabled.AsyncDebugger(flags))
{
AsyncDebugger.AsyncMethodUnhandledException(info.CurrentTask, ex, curContinuation);
}
}
}

public static void UnwindRuntimeAsyncMethodHandledException(AsyncInstrumentation.Flags flags, Continuation curContinuation, uint unwindedFrames)
public static void UnwindRuntimeAsyncMethodHandledException(ref AsyncDispatcherInfo info, AsyncInstrumentation.Flags flags, Continuation curContinuation, uint unwindedFrames)
{
if (AsyncInstrumentation.IsEnabled.AsyncProfiler(flags))
{
AsyncProfiler.ContinuationWrapper.UnwindIndex(ref info.AsyncProfilerInfo, unwindedFrames);
}

if (AsyncInstrumentation.IsEnabled.UnwindAsyncException(flags))
{
if (AsyncInstrumentation.IsEnabled.AsyncProfiler(flags))
{
AsyncProfiler.AsyncMethodException.Handled(ref info.AsyncProfilerInfo, unwindedFrames);
}

if (AsyncInstrumentation.IsEnabled.AsyncDebugger(flags))
{
AsyncDebugger.AsyncMethodHandledException(curContinuation, unwindedFrames);
Expand All @@ -1126,6 +1184,11 @@ public static void ResumeRuntimeAsyncMethod(ref AsyncDispatcherInfo info, AsyncI
{
if (AsyncInstrumentation.IsEnabled.ResumeAsyncMethod(flags))
{
if (AsyncInstrumentation.IsEnabled.AsyncProfiler(flags))
{
AsyncProfiler.ResumeAsyncMethod.Resume(ref info.AsyncProfilerInfo);
}

if (AsyncInstrumentation.IsEnabled.AsyncDebugger(flags))
{
AsyncDebugger.ResumeAsyncMethod(ref info, curContinuation);
Expand All @@ -1134,16 +1197,40 @@ public static void ResumeRuntimeAsyncMethod(ref AsyncDispatcherInfo info, AsyncI
}

[MethodImpl(MethodImplOptions.AggressiveInlining)]
public static void CompleteRuntimeAsyncMethod(AsyncInstrumentation.Flags flags, Continuation curContinuation)
public static void CompleteRuntimeAsyncMethod(ref AsyncDispatcherInfo info, AsyncInstrumentation.Flags flags, Continuation curContinuation)
{
if (AsyncInstrumentation.IsEnabled.AsyncProfiler(flags))
{
AsyncProfiler.ContinuationWrapper.IncrementIndex(ref info.AsyncProfilerInfo);
}

if (AsyncInstrumentation.IsEnabled.CompleteAsyncMethod(flags))
{
if (AsyncInstrumentation.IsEnabled.AsyncProfiler(flags))
{
AsyncProfiler.CompleteAsyncMethod.Complete(ref info.AsyncProfilerInfo);
}

if (AsyncInstrumentation.IsEnabled.AsyncDebugger(flags))
{
AsyncDebugger.CompleteAsyncMethod(curContinuation);
}
}
}

[MethodImpl(MethodImplOptions.AggressiveInlining)]
public static Continuation? ResumeContinuation(ref AsyncDispatcherInfo info, AsyncInstrumentation.Flags flags, Continuation curContinuation, ref byte resultLoc)
{
if (AsyncInstrumentation.IsEnabled.AsyncProfiler(flags))
{
return AsyncProfiler.ContinuationWrapper.Dispatch(ref info, curContinuation, ref resultLoc);
}

unsafe
{
return curContinuation.ResumeInfo->Resume(curContinuation, ref resultLoc);
}
}
}

internal static class AsyncDebugger
Expand Down
Loading
Loading