Re: [RFC][PATCH 6/8] mm: handle_speculative_fault()

[Arjan van de Ven]

On Mon, 04 Jan 2010 19:24:35 +0100
Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> wrote:

> Generic speculative fault handler, tries to service a pagefault
> without holding mmap_sem.


while I appreciate the goal of reducing contention on this lock...
wouldn't step one be to remove the page zeroing from under this lock?
that's by far (easily by 10x I would guess) the most expensive thing
that's done under the lock, and I would expect a first order of
contention reduction just by having the zeroing of a page not done
under the lock...


-- 
Arjan van de Ven 	Intel Open Source Technology Centre
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