[3.14] gh-137109: refactor warning about threads when forking (GH-141438) #141614
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LOL having used "Claude Code for the web" to do the backport means the email address isn't going to work for CLA checks. I'll force push an amended commit using my identity. |
…ythonGH-141438) This splits the OS API specific functionality to get the number of threads out from the fallback Python method and warning raising code itself. This way the OS APIs can be queried before we've run `os.register_at_fork(after_in_parent=...)` registered functions which themselves may (re)start threads that would otherwise be detected. This is best effort. If the OS APIs are either unavailable or fail, the warning generating code still falls back to looking at the Python threading state after the CPython interpreter world has been restarted and the after_in_parent calls have been made. The common case for most Linux and macOS environments should work today. This also lines up with the existing TODO refactoring, we may choose to expose this API to get the number of OS threads in the `os` module in the future. Note: This is a simplified backport that maintains the void return type for warn_about_fork_with_threads() and keeps PyErr_Clear() in the warning path, as the error handling changes from fd8f42d are not needed in 3.14.
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Thanks @gpshead for the PR 🌮🎉.. I'm working now to backport this PR to: 3.13. |
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…ythonGH-141438) (pythonGH-141614) This splits the OS API specific functionality to get the number of threads out from the fallback Python method and warning raising code itself. This way the OS APIs can be queried before we've run `os.register_at_fork(after_in_parent=...)` registered functions which themselves may (re)start threads that would otherwise be detected. This is best effort. If the OS APIs are either unavailable or fail, the warning generating code still falls back to looking at the Python threading state after the CPython interpreter world has been restarted and the after_in_parent calls have been made. The common case for most Linux and macOS environments should work today. This also lines up with the existing TODO refactoring, we may choose to expose this API to get the number of OS threads in the `os` module in the future. Note: This is a simplified backport that maintains the void return type for warn_about_fork_with_threads() and keeps PyErr_Clear() in the warning path, as the error handling changes from fd8f42d are not needed in 3.14. (cherry picked from commit 0d8fb0b) Co-authored-by: Gregory P. Smith <68491+gpshead@users.noreply.github.com>
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GH-141639 is a backport of this pull request to the 3.13 branch. |
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) (GH-141614) (GH-141639) [3.14] gh-137109: refactor warning about threads when forking (GH-141438) (GH-141614) This splits the OS API specific functionality to get the number of threads out from the fallback Python method and warning raising code itself. This way the OS APIs can be queried before we've run `os.register_at_fork(after_in_parent=...)` registered functions which themselves may (re)start threads that would otherwise be detected. This is best effort. If the OS APIs are either unavailable or fail, the warning generating code still falls back to looking at the Python threading state after the CPython interpreter world has been restarted and the after_in_parent calls have been made. The common case for most Linux and macOS environments should work today. This also lines up with the existing TODO refactoring, we may choose to expose this API to get the number of OS threads in the `os` module in the future. Note: This is a simplified backport that maintains the void return type for warn_about_fork_with_threads() and keeps PyErr_Clear() in the warning path, as the error handling changes from fd8f42d are not needed in 3.14. (cherry picked from commit 0d8fb0b) Co-authored-by: Gregory P. Smith <68491+gpshead@users.noreply.github.com>
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This splits the OS API specific functionality to get the number of threads out from the fallback Python method and warning raising code itself. This way the OS APIs can be queried before we've run
os.register_at_fork(after_in_parent=...)registered functions which themselves may (re)start threads that would otherwise be detected.This is best effort. If the OS APIs are either unavailable or fail, the warning generating code still falls back to looking at the Python threading state after the CPython interpreter world has been restarted and the after_in_parent calls have been made. The common case for most Linux and macOS environments should work today.
Note: This is a simplified backport that maintains the void return type for warn_about_fork_with_threads() and keeps PyErr_Clear() in the warning path, as the error handling changes from fd8f42d are not needed in 3.14 per discussion in #140191 on its own possible backport.