public inbox for linuxppc-dev@ozlabs.org
 help / color / mirror / Atom feed
From: Christophe Leroy <christophe.leroy@c-s.fr>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>,
	Paul Mackerras <paulus@samba.org>
Cc: scottwood@freescale.com, linuxppc-dev@lists.ozlabs.org,
	linux-kernel@vger.kernel.org
Subject: [PATCH v2] powerpc 8xx: defconfig: slice by 4 is more efficient than the default slice by 8 on Powerpc 8xx.
Date: Fri, 22 Nov 2013 18:28:29 +0100 (CET)	[thread overview]
Message-ID: <20131122172829.CC8EE1A4DE7@localhost.localdomain> (raw)

On PPC_8xx, CRC32_SLICEBY4 is more efficient (almost twice) than CRC32_SLICEBY8,
as shown below:

With CRC32_SLICEBY8:
[    1.109204] crc32: CRC_LE_BITS = 64, CRC_BE BITS = 64
[    1.114401] crc32: self tests passed, processed 225944 bytes in 15118910 nsec
[    1.130655] crc32c: CRC_LE_BITS = 64
[    1.134235] crc32c: self tests passed, processed 225944 bytes in 4479879 nsec

With CRC32_SLICEBY4:
[    1.097129] crc32: CRC_LE_BITS = 32, CRC_BE BITS = 32
[    1.101878] crc32: self tests passed, processed 225944 bytes in 8616242 nsec
[    1.116298] crc32c: CRC_LE_BITS = 32
[    1.119607] crc32c: self tests passed, processed 225944 bytes in 3289576 nsec

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>

diff -ur a/arch/powerpc/configs/adder875_defconfig b/arch/powerpc/configs.new/adder875_defconfig
--- a/arch/powerpc/configs/adder875_defconfig	2013-11-22 18:20:10.342968268 +0100
+++ b/arch/powerpc/configs.new/adder875_defconfig	2013-11-22 18:17:46.499686457 +0100
@@ -70,3 +70,4 @@
 CONFIG_DETECT_HUNG_TASK=y
 CONFIG_DEBUG_INFO=y
 # CONFIG_RCU_CPU_STALL_DETECTOR is not set
+CONFIG_CRC32_SLICEBY4=y
diff -ur a/arch/powerpc/configs/ep88xc_defconfig b/arch/powerpc/configs.new/ep88xc_defconfig
--- a/arch/powerpc/configs/ep88xc_defconfig	2013-11-22 18:20:10.286961148 +0100
+++ b/arch/powerpc/configs.new/ep88xc_defconfig	2013-11-22 18:17:41.992113565 +0100
@@ -72,3 +72,4 @@
 CONFIG_DETECT_HUNG_TASK=y
 CONFIG_DEBUG_INFO=y
 # CONFIG_RCU_CPU_STALL_DETECTOR is not set
+CONFIG_CRC32_SLICEBY4=y
diff -ur a/arch/powerpc/configs/mpc866_ads_defconfig b/arch/powerpc/configs.new/mpc866_ads_defconfig
--- a/arch/powerpc/configs/mpc866_ads_defconfig	2013-11-22 18:20:10.323965853 +0100
+++ b/arch/powerpc/configs.new/mpc866_ads_defconfig	2013-11-22 18:17:32.480904735 +0100
@@ -55,3 +55,4 @@
 CONFIG_CRC_CCITT=y
 # CONFIG_RCU_CPU_STALL_DETECTOR is not set
 # CONFIG_CRYPTO_ANSI_CPRNG is not set
+CONFIG_CRC32_SLICEBY4=y
diff -ur a/arch/powerpc/configs/mpc885_ads_defconfig b/arch/powerpc/configs.new/mpc885_ads_defconfig
--- a/arch/powerpc/configs/mpc885_ads_defconfig	2013-11-22 18:20:10.326966235 +0100
+++ b/arch/powerpc/configs.new/mpc885_ads_defconfig	2013-11-22 18:17:25.760050546 +0100
@@ -78,3 +78,4 @@
 CONFIG_DETECT_HUNG_TASK=y
 CONFIG_DEBUG_INFO=y
 # CONFIG_RCU_CPU_STALL_DETECTOR is not set
+CONFIG_CRC32_SLICEBY4=y
diff -ur a/arch/powerpc/configs/tqm8xx_defconfig b/arch/powerpc/configs.new/tqm8xx_defconfig
--- a/arch/powerpc/configs/tqm8xx_defconfig	2013-11-22 18:20:10.317965090 +0100
+++ b/arch/powerpc/configs.new/tqm8xx_defconfig	2013-11-22 18:17:14.926673681 +0100
@@ -84,3 +84,4 @@
 CONFIG_DETECT_HUNG_TASK=y
 CONFIG_DEBUG_INFO=y
 # CONFIG_RCU_CPU_STALL_DETECTOR is not set
+CONFIG_CRC32_SLICEBY4=y

             reply	other threads:[~2013-11-22 17:28 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-11-22 17:28 Christophe Leroy [this message]
2014-01-08  1:12 ` [v2] powerpc 8xx: defconfig: slice by 4 is more efficient than the default slice by 8 on Powerpc 8xx Scott Wood

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20131122172829.CC8EE1A4DE7@localhost.localdomain \
    --to=christophe.leroy@c-s.fr \
    --cc=benh@kernel.crashing.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linuxppc-dev@lists.ozlabs.org \
    --cc=paulus@samba.org \
    --cc=scottwood@freescale.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox