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| author | Ross Zwisler <ross.zwisler@linux.intel.com> | 2014-02-26 23:06:49 +0400 |
|---|---|---|
| committer | H. Peter Anvin <hpa@linux.intel.com> | 2014-02-27 20:23:28 +0400 |
| commit | 171699f7630c92d0a928f83e5fb3aeabe35398c0 (patch) | |
| tree | eab1cdc0b44666d92f391d345b5f2d668e4138d0 | |
| parent | c2bc11f10a39527cd1bb252097b5525664560956 (diff) | |
| download | linux-171699f7630c92d0a928f83e5fb3aeabe35398c0.tar.xz | |
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.zwisler@linux.intel.com>
Link: http://lkml.kernel.org/r/1393441612-19729-2-git-send-email-ross.zwisler@linux.intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
| -rw-r--r-- | arch/x86/include/asm/cpufeature.h | 1 | ||||
| -rw-r--r-- | arch/x86/include/asm/special_insns.h | 8 |
2 files changed, 9 insertions, 0 deletions
diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h index 5f1296872aed..bc507d7640f8 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 645cad2c95ff..e820c080a4e9 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") |