Re: [1/5] powerpc/mm: only call store_updates_sp() on stores in do_page_fault()
From: Michael Ellerman
Date: Mon Jun 05 2017 - 06:22:31 EST
On Wed, 2017-04-19 at 12:56:24 UTC, Christophe Leroy wrote:
> Function store_updates_sp() checks whether the faulting
> instruction is a store updating r1. Therefore we can limit its calls
> to stores exceptions.
>
> This patch is an improvement of commit a7a9dcd882a67 ("powerpc: Avoid
> taking a data miss on every userspace instruction miss")
>
> With the same microbenchmark app, run with 500 as argument, on an
> MPC885 we get:
>
> Before this patch: 152000 DTLB misses
> After this patch: 147000 DTLB misses
>
> Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>
> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxxxxxxx>
Patches 1, 3, 4 and 5 applied to powerpc next, thanks.
https://git.kernel.org/powerpc/c/e8de85ca32f572f5dee00733022d8a
cheers