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From: Michal Sojka <sojkam1@fel•cvut.cz>
To: LEROY Christophe <christophe.leroy@c-s•fr>
Cc: Scott Wood <scottwood@freescale•com>, linuxppc-dev@lists•ozlabs.org,
Subject: memcpy regression
Date: Fri, 04 Sep 2015 15:33:51 +0200	[thread overview]
Message-ID: <871teeux4w.fsf@steelpick.2x.cz> (raw)

Dear Christophe,

my MPC5200-based system stopped booting recently. I bisected the problem
to your commit below. If I revert that commit (on top of
807249d3ada1ff28a47c4054ca4edd479421b671 = v4.2-6663-g807249d), my
system boots again.

commit 0b05e2d671c40cfb57e66e4e402320d6e056b2f8
Author: LEROY Christophe <christophe.leroy@c-s•fr>
Date:   Tue May 19 12:07:55 2015 +0200

    powerpc/32: cacheable_memcpy becomes memcpy
    
    cacheable_memcpy uses dcbz instruction and is more efficient than
    memcpy when the destination is in RAM. If the destination is in an
    io area, memcpy_toio() is normally used, not memcpy
    
    This patch renames memcpy as generic_memcpy, and renames
    cacheable_memcpy as memcpy
    
    On MPC885, we get approximatly 7% increase of the transfer rate
    on an FTP reception
    
    Signed-off-by: Christophe Leroy <christophe.leroy@c-s•fr>
    Signed-off-by: Scott Wood <scottwood@freescale•com>

Best regards,
-Michal Sojka

             reply	other threads:[~2015-09-04 13:41 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-09-04 13:33 Michal Sojka [this message]
2015-09-04 13:57 ` memcpy regression Christophe LEROY
2015-09-04 14:35   ` Michal Sojka
2015-09-04 18:10     ` christophe leroy
2015-09-04 19:49       ` Michal Sojka
2015-09-05  0:08         ` Michal Sojka
2015-09-06  8:18           ` christophe leroy
2015-09-06 19:05             ` Michal Sojka
2015-09-06 21:01               ` Michal Sojka
2015-09-07  1:14                 ` Michael Ellerman
2015-09-07  7:08                   ` Christophe LEROY
2015-09-07  8:40                     ` Michael Ellerman
2015-09-07  9:45                       ` Michal Sojka
2015-09-07 10:59                         ` David Laight
2015-09-08  3:54                           ` Michael Ellerman
2015-09-08  8:59                             ` David Laight

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