linux-kernel - [PATCH v2] x86/cpufeatures: Add macros for Intel's new fast rep string features

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Message-ID: <20220831211810.2575536-1-jmattson@google.com>
Date:   Wed, 31 Aug 2022 14:18:10 -0700
From:   Jim Mattson <jmattson@...gle.com>
To:     Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>,
        Dave Hansen <dave.hansen@...ux.intel.com>, x86@...nel.org,
        "H. Peter Anvin" <hpa@...or.com>
Cc:     kvm@...r.kernel.org, Jim Mattson <jmattson@...gle.com>,
        linux-kernel@...r.kernel.org
Subject: [PATCH v2] x86/cpufeatures: Add macros for Intel's new fast rep
 string features

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@...gle.com>
---
 v1 -> v2: Hide from /proc/cpuinfo [Dave Hansen]

 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 ef4775c6db01..454f0faa8e90 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -308,6 +308,9 @@
 /* Intel-defined CPU features, CPUID level 0x00000007:1 (EAX), word 12 */
 #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_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} */
 
 /* AMD-defined CPU features, CPUID level 0x80000008 (EBX), word 13 */
 #define X86_FEATURE_CLZERO		(13*32+ 0) /* CLZERO instruction */
-- 
2.37.2.672.g94769d06f0-goog