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From:   ebiederm@xmission.com (Eric W. Biederman)
To:     Linus Torvalds <torvalds@linux-foundation.org>
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        Alan Stern <stern@rowland.harvard.edu>,
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        (Linus Torvalds's message of "Wed, 1 Apr 2020 19:05:59 -0700")
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Linus Torvalds <torvalds@linux-foundation.org> writes:

> tasklist_lock is aboue the hottest lock there is in all of the kernel.

Do you know code paths you see tasklist_lock being hot?

I am looking at some of the exec/signal/ptrace code paths because they
get subtle corner case wrong like a threaded exec deadlocking when
straced.

If the performance problems are in the same neighbourhood I might be
able to fix those problems while I am in the code.

Eric