Fix deadlock when a process is forked in the resume phase#691
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Fix deadlock when a process is forked in the resume phase#691
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We need to reset the `preResumeThreadCount` in the child process in the atfork_child handler. Otherwise, if a process is forked in the resume phase, this can lead to a deadlock, where the checkpoint thread that's created for the child process in the fork() wrapper gets blocked in waitForUserThreadsToFinishPreResumeCB(). This is because the child process inherits the non-zero value of `preResumeThreadCount` from the parent.
karya0
approved these changes
Sep 24, 2018
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We need to reset the
preResumeThreadCountin the child process in theatfork_child handler. Otherwise, if a process is forked in the resume
phase, this can lead to a deadlock, where the checkpoint thread that's
created for the child process in the fork() wrapper gets blocked in
waitForUserThreadsToFinishPreResumeCB(). This is because the child process
inherits the non-zero value of
preResumeThreadCountfrom the parent.