Commit-ID: 171699f7630c92d0a928f83e5fb3aeabe35398c0 Gitweb: http://git.kernel.org/tip/171699f7630c92d0a928f83e5fb3aeabe35398c0 Author: Ross Zwisler <ross.zwis...@linux.intel.com> AuthorDate: Wed, 26 Feb 2014 12:06:49 -0700 Committer: H. Peter Anvin <h...@linux.intel.com> CommitDate: Thu, 27 Feb 2014 08:23:28 -0800
x86: Add support for the clflushopt instruction Add support for the new clflushopt instruction. This instruction was announced in the document "Intel Architecture Instruction Set Extensions Programming Reference" with Ref # 319433-018. http://download-software.intel.com/sites/default/files/managed/50/1a/319433-018.pdf [ hpa: changed the feature flag to simply X86_FEATURE_CLFLUSHOPT - if that is what we want to report in /proc/cpuinfo anyway... ] Signed-off-by: Ross Zwisler <ross.zwis...@linux.intel.com> Link: http://lkml.kernel.org/r/1393441612-19729-2-git-send-email-ross.zwis...@linux.intel.com Signed-off-by: H. Peter Anvin <h...@linux.intel.com> --- arch/x86/include/asm/cpufeature.h | 1 + arch/x86/include/asm/special_insns.h | 8 ++++++++ 2 files changed, 9 insertions(+) diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h index 5f12968..bc507d7 100644 --- a/arch/x86/include/asm/cpufeature.h +++ b/arch/x86/include/asm/cpufeature.h @@ -221,6 +221,7 @@ #define X86_FEATURE_RDSEED (9*32+18) /* The RDSEED instruction */ #define X86_FEATURE_ADX (9*32+19) /* The ADCX and ADOX instructions */ #define X86_FEATURE_SMAP (9*32+20) /* Supervisor Mode Access Prevention */ +#define X86_FEATURE_CLFLUSHOPT (9*32+23) /* CLFLUSHOPT instruction */ #define X86_FEATURE_AVX512PF (9*32+26) /* AVX-512 Prefetch */ #define X86_FEATURE_AVX512ER (9*32+27) /* AVX-512 Exponential and Reciprocal */ #define X86_FEATURE_AVX512CD (9*32+28) /* AVX-512 Conflict Detection */ diff --git a/arch/x86/include/asm/special_insns.h b/arch/x86/include/asm/special_insns.h index 645cad2..e820c08 100644 --- a/arch/x86/include/asm/special_insns.h +++ b/arch/x86/include/asm/special_insns.h @@ -191,6 +191,14 @@ static inline void clflush(volatile void *__p) asm volatile("clflush %0" : "+m" (*(volatile char __force *)__p)); } +static inline void clflushopt(volatile void *__p) +{ + alternative_io(".byte " __stringify(NOP_DS_PREFIX) "; clflush %P0", + ".byte 0x66; clflush %P0", + X86_FEATURE_CLFLUSHOPT, + "+m" (*(volatile char __force *)__p)); +} + #define nop() asm volatile ("nop") -- 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/
