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From:   David Howells <dhowells@redhat.com>
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To:     Linus Torvalds <torvalds@linux-foundation.org>
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Subject: Re: [RFC PATCH 02/21] Add a prelocked wake-up
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Date:   Tue, 15 Oct 2019 23:33:16 +0100
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Linus Torvalds <torvalds@linux-foundation.org> wrote:

> > Add a wakeup call for a case whereby the caller already has the waitqueue
> > spinlock held.
> 
> That naming is crazy.

Sorry, yeah.  This is a bit hacked together at the moment and needs some more
tidying up.  I've had a lot of problems with performance regressions of up to
40% from seemingly simple changes involving moving locks around - it turns out
that the problem was that I was running with kasan enabled.

David