Don't try and instrument methods that are not tiering eligible#120241
Merged
AndyAyersMS merged 1 commit intodotnet:mainfrom Sep 30, 2025
Merged
Don't try and instrument methods that are not tiering eligible#120241AndyAyersMS merged 1 commit intodotnet:mainfrom
AndyAyersMS merged 1 commit intodotnet:mainfrom
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Under certain stress modes the JIT may enable PGO instrumentation even if the VM has not asked for it. On the VM side, block these attempts for methods that are not tiering eligible by ensuring that schema allocation requests immediately fail. Fixes dotnet#120237
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Pull Request Overview
This PR prevents the JIT from attempting to instrument methods that are not eligible for tiered compilation when PGO (Profile Guided Optimization) instrumentation is enabled. Under certain stress modes, the JIT might try to enable PGO instrumentation even when the VM hasn't requested it, which can cause issues.
Key changes:
- Adds a check to verify method tiering eligibility before proceeding with PGO instrumentation
- Returns E_NOTIMPL immediately for non-tiering-eligible methods to block unwanted instrumentation attempts
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/azp run runtime-coreclr libraries-pgo |
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Azure Pipelines successfully started running 1 pipeline(s). |
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EgorBo
approved these changes
Sep 30, 2025
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Under certain stress modes the JIT may enable PGO instrumentation even if the VM has not asked for it.
it sounds a little bit weird that JIT allows it to itself without the VM's permission, but I guess it allows us to keep the stress modes inside the JIT without expanding/moving it to VM
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Under certain stress modes the JIT may enable PGO instrumentation even if the VM has not asked for it. On the VM side, block these attempts for methods that are not tiering eligible by ensuring that schema allocation requests immediately fail.
Fixes #120237