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I tested the attached patch written by André Ramnitz using three different machines running a generic x86-64 kernel and an otherwise identical kernel running with the optimized gcc options. Conclusion: There are small but real speed increases using a make endpoint to running with this patch. Details: 1) Three test machines: Intel Xeon X3360, Intel i7-2620M, Intel Core i7-3660K. 2) All ran the make benchmark (linked below) 35 times while booted into a 'generic' kernel. Then all ran the same make benchmark 35 times after booting into an optimized kernel. Below are the optimizations chosen for each machine. 2a) X3360 = core2 2b) i7-2620M = corei7-avx 2c) i7-3660K = core-avx-i 3) Analyzed resulting distributions for statistical significance via ANOVA plots that clearly show statistically significant albeit small differences. Links to ANOVA plots: http://s19.postimage.org/68urcofzn/corei7_avx.png http://s19.postimage.org/ozwomuak3/core_avx_i.png http://s19.postimage.org/d0l6fj4z7/core2.png References: Bash script that controls the benchmark: https://github.com/graysky2/bin/blob/master/bench Log file generated by script: http://repo-ck.com/bench/compile_time_optimization.txt.gz --- --- linux-3.6/arch/x86/include/asm/module.h2012-04-29 18:43:58.239336240 -0700 +++ linux-3.6.mod/arch/x86/include/asm/module.h2012-04-29 18:43:41.609545221 -0700 @@ -17,6 +17,14 @@ #define MODULE_PROC_FAMILY "586MMX " #elif defined CONFIG_MCORE2 #define MODULE_PROC_FAMILY "CORE2 " +#elif defined CONFIG_MCOREI7 +#define MODULE_PROC_FAMILY "COREI7 " +#elif defined CONFIG_MCOREI7AVX +#define MODULE_PROC_FAMILY "COREI7AVX " +#elif defined CONFIG_MCOREAVXI +#define MODULE_PROC_FAMILY "COREAVXI " +#elif defined CONFIG_MCOREAVX2 +#define MODULE_PROC_FAMILY "COREAVX2 " #elif defined CONFIG_MATOM #define MODULE_PROC_FAMILY "ATOM " #elif defined CONFIG_M686 @@ -35,6 +43,14 @@ #define MODULE_PROC_FAMILY "K7 " #elif defined CONFIG_MK8 #define MODULE_PROC_FAMILY "K8 " +#elif defined CONFIG_MBARCELONA +#define MODULE_PROC_FAMILY "BARCELONA " +#elif defined CONFIG_MBOBCAT +#define MODULE_PROC_FAMILY "BOBCAT " +#elif defined CONFIG_MBULLDOZER +#define MODULE_PROC_FAMILY "BULLDOZER " +#elif defined CONFIG_MPILEDRIVER +#define MODULE_PROC_FAMILY "PILEDRIVER " #elif defined CONFIG_MELAN #define MODULE_PROC_FAMILY "ELAN " #elif defined CONFIG_MCRUSOE --- linux-3.6/arch/x86/Kconfig.cpu2012-04-29 18:43:58.249336198 -0700 +++ linux-3.6.mod/arch/x86/Kconfig.cpu2012-04-29 18:40:46.091751798 -0700 @@ -147,7 +147,7 @@ config MK6 -bool "K6/K6-II/K6-III" +bool "AMD K6/K6-II/K6-III" depends on X86_32 ---help--- Select this for an AMD K6-family processor. Enables use of @@ -155,7 +155,7 @@ flags to GCC. config MK7 -bool "Athlon/Duron/K7" +bool "AMD Athlon/Duron/K7" depends on X86_32 ---help--- Select this for an AMD Athlon K7-family processor. Enables use of @@ -163,12 +163,40 @@ flags to GCC. config MK8 -bool "Opteron/Athlon64/Hammer/K8" +bool "AMD Opteron/Athlon64/Hammer/K8" ---help--- Select this for an AMD Opteron or Athlon64 Hammer-family processor. Enables use of some extended instructions, and passes appropriate optimization flags to GCC. +config MBARCELONA +bool "AMD Barcelona" +---help--- + Select this for AMD Barcelona and newer processors. + + Enables -march=barcelona + +config MBOBCAT +bool "AMD Bobcat" +---help--- + Select this for AMD Bobcat processors. + + Enables -march=btver1 + +config MBULLDOZER +bool "AMD Bulldozer" +---help--- + Select this for AMD Bulldozer processors. + + Enables -march=bdver1 + +config MPILEDRIVER +bool "AMD Piledriver" +---help--- + Select this for AMD Piledriver processors. + + Enables -march=bdver2 + config MCRUSOE bool "Crusoe" depends on X86_32 @@ -260,7 +288,7 @@ in /proc/cpuinfo. Family 15 is an older Xeon, Family 6 a newer one. config MCORE2 -bool "Core 2/newer Xeon" +bool "Intel Core 2" ---help--- Select this for Intel Core 2 and newer Core 2 Xeons (Xeon 51xx and @@ -268,6 +296,41 @@ family in /proc/cpuinfo. Newer ones have 6 and older ones 15 (not a typo) + Enables -march=core2 + +config MCOREI7 +bool "Intel Core i7" +---help--- + + Select this for the Intel Nehalem platform. Intel Nehalem proecessors + include Core i3, i5, i7, Xeon: 34xx, 35xx, 55xx, 56xx, 75xx processors. + + Enables -march=corei7 + +config MCOREI7AVX +bool "Intel Core 2nd Gen AVX" +---help--- + + Select this for 2nd Gen Core processors including Sandy Bridge. + + Enables -march=corei7-avx + +config MCOREAVXI +bool "Intel Core 3rd Gen AVX" +---help--- + + Select this for 3rd Gen Core processors including Ivy Bridge. + + Enables -march=core-avx-i + +config MCOREAVX2 +bool "Intel Core AVX-2" +---help--- + + Select this for AVX-2 enabled processors including Haswell. + + Enables -march=corei7-avx-2 + config MATOM bool "Intel Atom" ---help--- @@ -312,7 +375,7 @@ config X86_L1_CACHE_SHIFT int default "7" if MPENTIUM4 || MPSC -default "6" if MK7 || MK8 || MPENTIUMM || MCORE2 || MATOM || MVIAC7 || X86_GENERIC || GENERIC_CPU +default "6" if MK7 || MK8 || MBARCELONA || MBOBCAT || MBULLDOZER || MPILEDRIVER || MPENTIUMM || MCORE2 || MCOREI7 || MCOREI7AVX || MCOREAVXI || MCOREAVX2 || MATOM || MVIAC7 || X86_GENERIC || GENERIC_CPU default "4" if MELAN || M486 || M386 || MGEODEGX1 default "5" if MWINCHIP3D || MWINCHIPC6 || MCRUSOE || MEFFICEON || MCYRIXIII || MK6 || MPENTIUMIII || MPENTIUMII || M686 || M586MMX || M586TSC || M586 || MVIAC3_2 || MGEODE_LX @@ -363,11 +426,11 @@ config X86_INTEL_USERCOPY def_bool y -depends on MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M586MMX || X86_GENERIC || MK8 || MK7 || MEFFICEON || MCORE2 +depends on MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M586MMX || X86_GENERIC || MK8 || MK7 || MBARCELONA || MEFFICEON || MCORE2 || MCOREI7 || MCOREI7AVX || MCOREAVXI || MCOREAVX2 config X86_USE_PPRO_CHECKSUM def_bool y -depends on MWINCHIP3D || MWINCHIPC6 || MCYRIXIII || MK7 || MK6 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MK8 || MVIAC3_2 || MVIAC7 || MEFFICEON || MGEODE_LX || MCORE2 || MATOM +depends on MWINCHIP3D || MWINCHIPC6 || MCYRIXIII || MK7 || MK6 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MK8 || MVIAC3_2 || MVIAC7 || MEFFICEON || MGEODE_LX || MCORE2 || MCOREI7 || MCOREI7AVX || MCOREAVXI || MCOREAVX2 || MATOM config X86_USE_3DNOW def_bool y @@ -395,17 +458,17 @@ config X86_TSC def_bool y -depends on ((MWINCHIP3D || MCRUSOE || MEFFICEON || MCYRIXIII || MK7 || MK6 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || M586MMX || M586TSC || MK8 || MVIAC3_2 || MVIAC7 || MGEODEGX1 || MGEODE_LX || MCORE2 || MATOM) && !X86_NUMAQ) || X86_64 +depends on ((MWINCHIP3D || MCRUSOE || MEFFICEON || MCYRIXIII || MK7 || MK6 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || M586MMX || M586TSC || MK8 || MBARCELONA || MBOBCAT || MBULLDOZER || MPILEDRIVER || MVIAC3_2 || MVIAC7 || MGEODEGX1 || MGEODE_LX || MCORE2 || MCOREI7 || MCOREI7-AVX || MATOM) && !X86_NUMAQ) || X86_64 config X86_CMPXCHG64 def_bool y -depends on X86_PAE || X86_64 || MCORE2 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MATOM +depends on X86_PAE || X86_64 || MCORE2 || MCOREI7 || MCOREI7AVX || MCOREAVXI || MCOREAVX2 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MATOM # this should be set for all -march=.. options where the compiler # generates cmov. config X86_CMOV def_bool y -depends on (MK8 || MK7 || MCORE2 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MVIAC3_2 || MVIAC7 || MCRUSOE || MEFFICEON || X86_64 || MATOM || MGEODE_LX) +depends on (MK8 || MBARCELONA || MBOBCAT || MBULLDOZER || MPILEDRIVER || MK7 || MCORE2 || MCOREI7 || MCOREI7AVX || MCOREAVXI || MCOREAVX2 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MVIAC3_2 || MVIAC7 || MCRUSOE || MEFFICEON || X86_64 || MATOM || MGEODE_LX) config X86_MINIMUM_CPU_FAMILY int --- linux-3.6/arch/x86/Makefile2012-04-29 18:43:58.249336198 -0700 +++ linux-3.6.mod/arch/x86/Makefile2012-04-29 18:41:51.260932642 -0700 @@ -51,10 +51,22 @@ # FIXME - should be integrated in Makefile.cpu (Makefile_32.cpu) cflags-$(CONFIG_MK8) += $(call cc-option,-march=k8) + cflags-$(CONFIG_MBARCELONA) += $(call cc-option,-march=barcelona) + cflags-$(CONFIG_MBOBCAT) += $(call cc-option,-march=btver1) + cflags-$(CONFIG_MBULLDOZER) += $(call cc-option,-march=bdver1) + cflags-$(CONFIG_MPILEDRIVER) += $(call cc-option,-march=bdver2) cflags-$(CONFIG_MPSC) += $(call cc-option,-march=nocona) cflags-$(CONFIG_MCORE2) += \ - $(call cc-option,-march=core2,$(call cc-option,-mtune=generic)) + $(call cc-option,-march=core2,$(call cc-option,-mtune=core2)) + cflags-$(CONFIG_MCOREI7) += \ + $(call cc-option,-march=corei7,$(call cc-option,-mtune=corei7)) + cflags-$(CONFIG_MCOREI7AVX) += \ + $(call cc-option,-march=corei7-avx,$(call cc-option,-mtune=corei7-avx)) + cflags-$(CONFIG_MCOREAVXI) += \ + $(call cc-option,-march=core-avx-i,$(call cc-option,-mtune=core-avx-i)) + cflags-$(CONFIG_MCOREAVX2) += \ + $(call cc-option,-march=core-avx2,$(call cc-option,-mtune=core-avx2)) cflags-$(CONFIG_MATOM) += $(call cc-option,-march=atom) \ $(call cc-option,-mtune=atom,$(call cc-option,-mtune=generic)) cflags-$(CONFIG_GENERIC_CPU) += $(call cc-option,-mtune=generic) --- linux-3.6/arch/x86/Makefile_32.cpu2012-04-29 18:43:58.269335977 -0700 +++ linux-3.6.mod/arch/x86/Makefile_32.cpu2012-04-29 18:42:39.120330975 -0700 @@ -25,6 +25,10 @@ # They make zero difference whatsosever to performance at this time. cflags-$(CONFIG_MK7)+= -march=athlon cflags-$(CONFIG_MK8)+= $(call cc-option,-march=k8,-march=athlon) +cflags-$(CONFIG_MBARCELONA)+= $(call cc-option,-march=barcelona,-march=athlon) +cflags-$(CONFIG_MBOBCAT)+= $(call cc-option,-march=btver1,-march=athlon) +cflags-$(CONFIG_MBULLDOZER)+= $(call cc-option,-march=bdver1,-march=athlon) +cflags-$(CONFIG_MPILEDRIVER)+= $(call cc-option,-march=bdver2,-march=athlon) cflags-$(CONFIG_MCRUSOE)+= -march=i686 $(align)-functions=0 $(align)-jumps=0 $(align)-loops=0 cflags-$(CONFIG_MEFFICEON)+= -march=i686 $(call tune,pentium3) $(align)-functions=0 $(align)-jumps=0 $(align)-loops=0 cflags-$(CONFIG_MWINCHIPC6)+= $(call cc-option,-march=winchip-c6,-march=i586) @@ -33,6 +37,10 @@ cflags-$(CONFIG_MVIAC3_2)+= $(call cc-option,-march=c3-2,-march=i686) cflags-$(CONFIG_MVIAC7)+= -march=i686 cflags-$(CONFIG_MCORE2)+= -march=i686 $(call tune,core2) +cflags-$(CONFIG_MCOREI7)+= -march=i686 $(call tune,corei7) +cflags-$(CONFIG_MCOREI7AVX)+= -march=i686 $(call tune,corei7-avx) +cflags-$(CONFIG_MCOREAVXI)+= -march=i686 $(call tune,core-avx-i) +cflags-$(CONFIG_MCOREAVX2)+= -march=i686 $(call tune,core-avx-2) cflags-$(CONFIG_MATOM)+= $(call cc-option,-march=atom,$(call cc-option,-march=core2,-march=i686)) \ $(call cc-option,-mtune=atom,$(call cc-option,-mtune=generic)) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/