Re: [RFC PATCH 02/21] Add a prelocked wake-up

From: David Howells
Date: Tue Oct 15 2019 - 18:33:23 EST

Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> 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.