[Backport][main to 0.9] | fix(alog): prevent child deadlock on rotation lock across fork() (#1573) - #1575
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lihuiba merged 1 commit intoJul 28, 2026
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The log rotation mutex was a function-local static in write(). If fork() happened while another thread was rotating, the child inherited the mutex permanently locked and deadlocked on its next rotation. Hoist the lock to file scope and serialize it against fork() with pthread_atfork(): prepare acquires it (waiting out any in-flight rotation), and both parent and child release it afterwards. Add a fork-during-rotation regression test.
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…) (#1575) (#1577) The log rotation mutex was a function-local static in write(). If fork() happened while another thread was rotating, the child inherited the mutex permanently locked and deadlocked on its next rotation. Hoist the lock to file scope and serialize it against fork() with pthread_atfork(): prepare acquires it (waiting out any in-flight rotation), and both parent and child release it afterwards. Add a fork-during-rotation regression test. Co-authored-by: Coldwings <coldwings@me.com>
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…n lock across fork() (#1573) (#1575) (#1577) (#1579) * fix(alog): prevent child deadlock on rotation lock across fork() (#1573) (#1575) (#1577) The log rotation mutex was a function-local static in write(). If fork() happened while another thread was rotating, the child inherited the mutex permanently locked and deadlocked on its next rotation. Hoist the lock to file scope and serialize it against fork() with pthread_atfork(): prepare acquires it (waiting out any in-flight rotation), and both parent and child release it afterwards. Add a fork-during-rotation regression test. Co-authored-by: Coldwings <coldwings@me.com> * Update alog.cpp --------- Co-authored-by: Coldwings <coldwings@me.com>
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…ion lock across fork() (#1573) (#1575) (#1577) (#1579) (#1582) * [Backport][0.8 to 0.7] | fix(alog): prevent child deadlock on rotation lock across fork() (#1573) (#1575) (#1577) (#1579) * fix(alog): prevent child deadlock on rotation lock across fork() (#1573) (#1575) (#1577) The log rotation mutex was a function-local static in write(). If fork() happened while another thread was rotating, the child inherited the mutex permanently locked and deadlocked on its next rotation. Hoist the lock to file scope and serialize it against fork() with pthread_atfork(): prepare acquires it (waiting out any in-flight rotation), and both parent and child release it afterwards. Add a fork-during-rotation regression test. Co-authored-by: Coldwings <coldwings@me.com> * Update alog.cpp --------- Co-authored-by: Coldwings <coldwings@me.com> * Update test_alog.cpp * Update test_alog.cpp --------- Co-authored-by: Coldwings <coldwings@me.com> Co-authored-by: Huiba Li <huiba.lhb@alibaba-inc.com>
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The log rotation mutex was a function-local static in write(). If fork() happened while another thread was rotating, the child inherited the mutex permanently locked and deadlocked on its next rotation. Hoist the lock to file scope and serialize it against fork() with pthread_atfork(): prepare acquires it (waiting out any in-flight rotation), and both parent and child release it afterwards. Add a fork-during-rotation regression test.
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