[3.14] gh-136396: Include instrumentation when creating new copies of the bytecode (GH-136525) #136657
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…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]>
This was referenced Jul 14, 2025
colesbury
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…ies of the bytecode (pythonGH-136525) (pythonGH-136657) 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]> Co-authored-by: Kumar Aditya <[email protected]>
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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.
(cherry picked from commit d995922)
Co-authored-by: mpage [email protected]