[SRU L][PATCH 2/2] x86/cpufeatures: Add macros for Intel's new fast rep string features

Jeff Lane jeffrey.lane at canonical.com
Fri Dec 15 07:39:01 UTC 2023


From: Jim Mattson <jmattson at google.com>

BugLink: https://bugs.launchpad.net/bugs/2020022

KVM_GET_SUPPORTED_CPUID should reflect these host CPUID bits. The bits
are already cached in word 12. Give the bits X86_FEATURE names, so
that they can be easily referenced. Hide these bits from
/proc/cpuinfo, since the host kernel makes no use of them at present.

Signed-off-by: Jim Mattson <jmattson at google.com>
Reviewed-by: Sean Christopherson <seanjc at google.com>
Link: https://lore.kernel.org/r/20220901211811.2883855-1-jmattson@google.com
Signed-off-by: Sean Christopherson <seanjc at google.com>
(cherry picked from commit f8df91e73a6827a4569bb56cd53e55b4ea2f5b1f)
Signed-off-by: Michael Reed <Michael.Reed at canonical.com>
---
 arch/x86/include/asm/cpufeatures.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
index cfd280a5aaca..5facbd897fa2 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -316,6 +316,9 @@
 #define X86_FEATURE_AVX_VNNI		(12*32+ 4) /* AVX VNNI instructions */
 #define X86_FEATURE_AVX512_BF16		(12*32+ 5) /* AVX512 BFLOAT16 instructions */
 #define X86_FEATURE_CMPCCXADD           (12*32+ 7) /* "" CMPccXADD instructions */
+#define X86_FEATURE_FZRM		(12*32+10) /* "" Fast zero-length REP MOVSB */
+#define X86_FEATURE_FSRS		(12*32+11) /* "" Fast short REP STOSB */
+#define X86_FEATURE_FSRC		(12*32+12) /* "" Fast short REP {CMPSB,SCASB} */
 #define X86_FEATURE_AMX_FP16		(12*32+21) /* "" AMX fp16 Support */
 #define X86_FEATURE_AVX_IFMA            (12*32+23) /* "" Support for VPMADD52[H,L]UQ */
 
-- 
2.34.1




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