lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Tue, 16 Sep 2014 10:49:14 +1000 From: Anton Blanchard <anton@...ba.org> To: benh@...nel.crashing.org, paulus@...ba.org, michael@...erman.id.au, torvalds@...ux-foundation.org Cc: linuxppc-dev@...ts.ozlabs.org, linux-kernel@...r.kernel.org Subject: [PATCH 2/2] powerpc: Use CONFIG_ARCH_HAS_FAST_MULTIPLIER I ran some tests to compare hash_64 using shifts and multiplies. The results: POWER6: ~2x slower POWER7: ~2x faster POWER8: ~2x faster Now we have a proper config option, select CONFIG_ARCH_HAS_FAST_MULTIPLIER on POWER7 and POWER8. Signed-off-by: Anton Blanchard <anton@...ba.org> --- Index: b/arch/powerpc/platforms/Kconfig.cputype =================================================================== --- a/arch/powerpc/platforms/Kconfig.cputype +++ b/arch/powerpc/platforms/Kconfig.cputype @@ -116,10 +116,12 @@ config POWER6_CPU config POWER7_CPU bool "POWER7" depends on PPC_BOOK3S_64 + select ARCH_HAS_FAST_MULTIPLIER config POWER8_CPU bool "POWER8" depends on PPC_BOOK3S_64 + select ARCH_HAS_FAST_MULTIPLIER config E5500_CPU bool "Freescale e5500" -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists