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Re: [PATCH v3] powerpc32: memset: only use dcbz once cache is enabled

From Michal Sojka <sojkam1@fel.cvut.cz>
Newsgroups linux.kernel
Subject Re: [PATCH v3] powerpc32: memset: only use dcbz once cache is enabled
Date 2015-09-14 09:20 +0200
Message-ID <q8wdr-7CL-7@gated-at.bofh.it> (permalink)
References <q8vr4-6t7-3@gated-at.bofh.it>
Organization linux.* mail to news gateway

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On Mon, Sep 14 2015, Christophe Leroy wrote:
> memset() uses instruction dcbz to speed up clearing by not wasting time
> loading cache line with data that will be overwritten.
> Some platform like mpc52xx do no have cache active at startup and
> can therefore not use memset(). Allthough no part of the code
> explicitly uses memset(), GCC may makes calls to it.
>
> This patch modifies memset() such that at startup, memset()
> unconditionally jumps to simple_memset() which doesn't use
> the dcbz instruction.

I tested both v3 patches (memcpy and memset) and they work for me.

Thanks
-Michal
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Thread

[PATCH v3] powerpc32: memset: only use dcbz once cache is enabled Christophe Leroy <christophe.leroy@c-s.fr> - 2015-09-14 08:30 +0200
  Re: [PATCH v3] powerpc32: memset: only use dcbz once cache is enabled Michal Sojka <sojkam1@fel.cvut.cz> - 2015-09-14 09:20 +0200
  Re: [PATCH v3] powerpc32: memset: only use dcbz once cache is  enabled Scott Wood <scottwood@freescale.com> - 2015-09-14 17:30 +0200
    Re: [PATCH v3] powerpc32: memset: only use dcbz once cache is enabled Christophe LEROY <christophe.leroy@c-s.fr> - 2015-09-14 17:50 +0200
      Re: [PATCH v3] powerpc32: memset: only use dcbz once cache is  enabled Scott Wood <scottwood@freescale.com> - 2015-09-14 18:20 +0200
        Re: [PATCH v3] powerpc32: memset: only use dcbz once cache is  enabled Michael Ellerman <mpe@ellerman.id.au> - 2015-09-15 02:00 +0200

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