Fix RuntimeError caused by logging in the SIGCHLD signal handler #2667
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@BoasKluiving thanks for the PR. b695b49 was reverted by 76f8da2 having the same effect, so closing this PR. |
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This PR is to fix an issue introduced by b695b49. This issue is also described in #2564. The problem is that we are logging something in the signal handler, which is not reentrant.
The issue occurs if Gunicorn happens to be logging something (for example here) and gets interrupted by SIGCHLD at that moment. This invokes the signal handler handle_chld() (here), which calls reap_workers().
reap_workers() however logs a warning here, causing the following RuntimeError:
RuntimeError: reentrant call inside <_io.BufferedWriter name='<stderr>'>Operations on BufferedWriter are unfortunately not reentrant, so we can only fix this by (a) not logging in the signal handler or (b) only setting a flag in signal handler and do the processing later.
This PR fixes the problem by removing the log message in the signal handler.