gh-136396: Include instrumentation when creating new copies of the bytecode #136525
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Previously, we assumed that instrumentation would happen for all copies of the bytecode if the instrumentation version on the code object didn't match the per-interpreter instrumentation version. That assumption was incorrect: instrumentation will exit early if there are no new "events," even if there is an instrumentation version mismatch. To fix this, include the instrumented opcodes when creating new copies of the bytecode, rather than replacing them with their uninstrumented variants. I don't think we have to worry about races between instrumentation and creating new copies of the bytecode: instrumentation and new bytecode creation cannot happen concurrently. Instrumentation requires that either the world is stopped or the code object's per-object lock is held and new bytecode creation requires holding the code object's per-object lock.
colesbury
approved these changes
Jul 11, 2025
Yhg1s
approved these changes
Jul 14, 2025
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Thanks @mpage for the PR 🌮🎉.. I'm working now to backport this PR to: 3.14. |
miss-islington
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Jul 14, 2025
…the bytecode (pythonGH-136525) Previously, we assumed that instrumentation would happen for all copies of the bytecode if the instrumentation version on the code object didn't match the per-interpreter instrumentation version. That assumption was incorrect: instrumentation will exit early if there are no new "events," even if there is an instrumentation version mismatch. To fix this, include the instrumented opcodes when creating new copies of the bytecode, rather than replacing them with their uninstrumented variants. I don't think we have to worry about races between instrumentation and creating new copies of the bytecode: instrumentation and new bytecode creation cannot happen concurrently. Instrumentation requires that either the world is stopped or the code object's per-object lock is held and new bytecode creation requires holding the code object's per-object lock. (cherry picked from commit d995922) Co-authored-by: mpage <[email protected]>
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GH-136657 is a backport of this pull request to the 3.14 branch. |
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Previously, we assumed that instrumentation would happen for all copies of the bytecode if the instrumentation version on the code object didn't match the per-interpreter instrumentation version. That assumption was incorrect: instrumentation will exit early if there are no new "events," even if there is an instrumentation version mismatch.
To fix this, include the instrumented opcodes when creating new copies of the bytecode, rather than replacing them with their uninstrumented variants. I don't think we have to worry about races between instrumentation and creating new copies of the bytecode as they cannot happen concurrently. Instrumentation requires that either the world is stopped or the code object's per-object lock is held, while new bytecode creation requires holding the code object's per-object lock.