Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux

powerpc 8xx: defconfig: slice by 4 is more efficient than the default slice by 8 on Powerpc 8xx.

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>
Signed-off-by: Scott Wood <scottwood@freescale.com>

authored by

LEROY Christophe and committed by
Scott Wood
18904698 8a6be2bd

+5
+1
arch/powerpc/configs/adder875_defconfig
··· 70 70 CONFIG_DETECT_HUNG_TASK=y 71 71 CONFIG_DEBUG_INFO=y 72 72 # CONFIG_RCU_CPU_STALL_DETECTOR is not set 73 + CONFIG_CRC32_SLICEBY4=y
+1
arch/powerpc/configs/ep88xc_defconfig
··· 72 72 CONFIG_DETECT_HUNG_TASK=y 73 73 CONFIG_DEBUG_INFO=y 74 74 # CONFIG_RCU_CPU_STALL_DETECTOR is not set 75 + CONFIG_CRC32_SLICEBY4=y
+1
arch/powerpc/configs/mpc866_ads_defconfig
··· 55 55 CONFIG_CRC_CCITT=y 56 56 # CONFIG_RCU_CPU_STALL_DETECTOR is not set 57 57 # CONFIG_CRYPTO_ANSI_CPRNG is not set 58 + CONFIG_CRC32_SLICEBY4=y
+1
arch/powerpc/configs/mpc885_ads_defconfig
··· 78 78 CONFIG_DETECT_HUNG_TASK=y 79 79 CONFIG_DEBUG_INFO=y 80 80 # CONFIG_RCU_CPU_STALL_DETECTOR is not set 81 + CONFIG_CRC32_SLICEBY4=y
+1
arch/powerpc/configs/tqm8xx_defconfig
··· 84 84 CONFIG_DETECT_HUNG_TASK=y 85 85 CONFIG_DEBUG_INFO=y 86 86 # CONFIG_RCU_CPU_STALL_DETECTOR is not set 87 + CONFIG_CRC32_SLICEBY4=y