From: Avi Kivity <avi-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
Subject: Re: [patch 2/2]: introduce fast_gup
Date: Tue, 22 Apr 2008 10:19:08 +0300
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To: Nick Piggin <npiggin-l3A5Bk7waGM@public.gmane.org>
Cc: Peter Zijlstra <peterz-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>, Linus Torvalds <torvalds-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>, Andrew Morton <akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>, shaggy-V7BBcbaFuwjMbYB6QlFGEg@public.gmane.org, axboe-tSWWG44O7X1aa/9Udqfwiw@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, linux-arch-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Clark Williams <williams-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>, Ingo Molnar <mingo-X9Un+BFzKDI@public.gmane.org>, "H. Peter Anvin" <hpa-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org>

Nick Piggin wrote:
> That's horrible ;)
>
> Anyway guys you are missing the other side of the equation -- that whenever
> _PAGE_PRESENT is cleared, all CPUs where current->mm might be == mm have to
> have a tlb flush. And we're holding off tlb flushes in fast_gup, that's the
> whole reason why it all works.
>
>   

Ah, clever.  Thanks.

-- 
error compiling committee.c: too many arguments to function