[wasm][mt] throw from blocking wait on JS interop threads

[radekdoulik]

Also add test

Contributes to #76958

[dotnet-issue-labeler]

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[radekdoulik]

The current approach doesn't solve the blocking wait in JS interop, which is then throwing the exception for us too.

[20:37:25] fail: MONO_WASM:    at System.Threading.Monitor.Wait(Object obj, Int32 millisecondsTimeout)
                    at System.Threading.ManualResetEventSlim.Wait(Int32 millisecondsTimeout, CancellationToken cancellationToken)
                    at System.Threading.ManualResetEventSlim.Wait()
                    at System.Runtime.InteropServices.JavaScript.JavaScriptExports.CompleteTask(JSMarshalerArgument* arguments_buffer)
                 Error: blocking Wait is not supported on the JS interop thread.
                     at wr (http://127.0.0.1:42115/_framework/dotnet.runtime.js:3:35092)
                     at Qo (http://127.0.0.1:42115/_framework/dotnet.runtime.js:3:73035)
                     at p.javaScriptExports.complete_task (http://127.0.0.1:42115/_framework/dotnet.runtime.js:3:248198)
                     at http://127.0.0.1:42115/_framework/dotnet.runtime.js:3:80721

We discussed it in chat and agreed on the introduction of a new flag to signal that the wait comes from JS interop code. The flag can be added to the Monitor class and thus simplify the thread JS interop thread detection.

[radekdoulik]

New fail to look into:

[16:54:41] info: [2024-01-19T16:54:41.880Z] [FAIL] System.Runtime.InteropServices.JavaScript.Tests.WebWorkerTest.JSSynchronizationContext_Send_Post_Items_Cancellation
[16:54:41] info: Assert.Throws() Failure: Exception type was not an exact match
[16:54:41] info: Expected: typeof(System.OperationCanceledException)
[16:54:41] info: Actual:   typeof(System.ObjectDisposedException)
[16:54:41] info: ---- System.ObjectDisposedException : Cannot access a disposed object.
[16:54:41] info: Object name: 'System.Runtime.InteropServices.JavaScript.JSSynchronizationContext'.
[16:54:41] info:    at System.Runtime.InteropServices.JavaScript.Tests.WebWorkerTest.JSSynchronizationContext_Send_Post_Items_Cancellation()
[16:54:41] info: --- End of stack trace from previous location ---
[16:54:41] info: ----- Inner Stack Trace -----
[16:54:41] info:    at System.Runtime.InteropServices.JavaScript.JSSynchronizationContext.Send(SendOrPostCallback , Object )
[16:54:41] info:    at System.Runtime.InteropServices.JavaScript.Tests.WebWorkerTest.<>c__DisplayClass6_0.<JSSynchronizationContext_Send_Post_Items_Cancellation>b__1()
[16:54:41] info:    at System.Threading.Tasks.Task`1[[System.Threading.Tasks.Task, System.Private.CoreLib, Version=9.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].InnerInvoke()
[16:54:41] info:    at System.Threading.Tasks.Task.<>c.<.cctor>b__281_0(Object obj)
[16:54:41] info:    at System.Threading.ExecutionContext.RunFromThreadPoolDispatchLoop(Thread , ExecutionContext , ContextCallback , Object )
[16:54:41] info: --- End of stack trace from previous location ---
[16:54:41] info:    at System.Threading.ExecutionContext.RunFromThreadPoolDispatchLoop(Thread , ExecutionContext , ContextCallback , Object )
[16:54:41] info:    at System.Threading.Tasks.Task.ExecuteWithThreadLocal(Task& , Thread )
[16:54:41] info: --- End of stack trace from previous location ---

[pavelsavara]

New fail to look into:

It's unrelated to your PR, please add it to #96628

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Azure Pipelines successfully started running 1 pipeline(s).

[radekdoulik]

/azp run runtime-wasm

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Azure Pipelines successfully started running 1 pipeline(s).

[pavelsavara]

Log

[16:55:56] fail: [FAIL] System.Runtime.InteropServices.JavaScript.Tests.WebWorkerTest.JSSynchronizationContext_Send_Post_Items_Cancellation
[16:55:56] info: Assert.ThrowsAny() Failure: Exception type was not compatible
[16:55:56] info: Expected: typeof(System.OperationCanceledException)
[16:55:56] info: Actual:   typeof(System.ObjectDisposedException)

This is unrelated.

[pavelsavara]

🎉

[pavelsavara]

Quick list of APIs, for which we need to validate that they internally use something we already addressed so far.
Or we need to address them too.

• Task - WaitAll, WaitAny
• WaitSubsystem - Wait
• WaitableObject - .Wait, SatisfyWaitForAll, Wait_Locked
• ThreadWaitInfo - .Wait, Sleep,
• LowLevelLock - WaitAndAcquire
• LowLevelMonitor - Wait, Acquire
• LowLevelSpinWaiter - Wait
• LowLevelLifoSemaphore - Wait
• FileSystemWatcher - WaitForChanged
• GC - WaitForFullGCApproach, WaitForFullGCComplete, WaitForPendingFinalizers
• CancellationTokenSource - WaitForCallbackToComplete
• ManualResetEventSlim - Wait
• SemaphoreSlim - Wait
• SynchronizationContext - Wait
• WaitHandle - WaitOne, WaitAll
• ManualResetEventWithAwaiterSupport - Wait
• CountdownEvent - Wait
• Interop.Sys.LowLevelMonitor_TimedWait & SystemNative_LowLevelMonitor_Wait

I'm sure I missed some places.

[radekdoulik]

Lets get this in and I can extend the tests and API coverage in follow up PR.

[pavelsavara]

Let's make helper method for this and localize the message.
The method should be "public" but suppressed same like ThrowOnBlockingWaitOnJSInteropThread.
So that we could use it in other places in the runtime.

[pavelsavara]

should this be in try-finally ?
could .Wait ever throw ?
@radekdoulik

[pavelsavara]

I'll will change that on my PR #97832

[pavelsavara]

This is unrelated.

It was actually related but hiding behind another problem.
This is now throwing PNSE (as it should), but the test was not ready for it.

runtime/src/libraries/System.Runtime.InteropServices.JavaScript/tests/System.Runtime.InteropServices.JavaScript.UnitTests/System/Runtime/InteropServices/JavaScript/WebWorkerTest.cs

Line 88 in 5cee418

blocker.Wait();

I'm fixing it in #97832