From d6d0c7f681fda1d07e005c8f653e578b77a0eb40 Mon Sep 17 00:00:00 2001 From: Sandipan Das Date: Thu, 21 Apr 2022 11:16:53 +0530 Subject: [PATCH] x86/cpufeatures: Add PerfMonV2 feature bit CPUID leaf 0x80000022 i.e. ExtPerfMonAndDbg advertises some new performance monitoring features for AMD processors. Bit 0 of EAX indicates support for Performance Monitoring Version 2 (PerfMonV2) features. If found to be set during PMU initialization, the EBX bits of the same CPUID function can be used to determine the number of available PMCs for different PMU types. Additionally, Core PMCs can be managed using new global control and status registers. For better utilization of feature words, PerfMonV2 is added as a scattered feature bit. Signed-off-by: Sandipan Das Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/c70e497e22f18e7f05b025bb64ca21cc12b17792.1650515382.git.sandipan.das@amd.com --- arch/x86/include/asm/cpufeatures.h | 2 +- arch/x86/kernel/cpu/scattered.c | 1 + 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h index 0d62afd525e3..b50e0872ad1e 100644 --- a/arch/x86/include/asm/cpufeatures.h +++ b/arch/x86/include/asm/cpufeatures.h @@ -211,7 +211,7 @@ #define X86_FEATURE_SSBD ( 7*32+17) /* Speculative Store Bypass Disable */ #define X86_FEATURE_MBA ( 7*32+18) /* Memory Bandwidth Allocation */ #define X86_FEATURE_RSB_CTXSW ( 7*32+19) /* "" Fill RSB on context switches */ -/* FREE! ( 7*32+20) */ +#define X86_FEATURE_PERFMON_V2 ( 7*32+20) /* AMD Performance Monitoring Version 2 */ #define X86_FEATURE_USE_IBPB ( 7*32+21) /* "" Indirect Branch Prediction Barrier enabled */ #define X86_FEATURE_USE_IBRS_FW ( 7*32+22) /* "" Use IBRS during runtime firmware calls */ #define X86_FEATURE_SPEC_STORE_BYPASS_DISABLE ( 7*32+23) /* "" Disable Speculative Store Bypass. */ diff --git a/arch/x86/kernel/cpu/scattered.c b/arch/x86/kernel/cpu/scattered.c index 4143b1e4c5c6..dbaa8326d6f2 100644 --- a/arch/x86/kernel/cpu/scattered.c +++ b/arch/x86/kernel/cpu/scattered.c @@ -43,6 +43,7 @@ static const struct cpuid_bit cpuid_bits[] = { { X86_FEATURE_CPB, CPUID_EDX, 9, 0x80000007, 0 }, { X86_FEATURE_PROC_FEEDBACK, CPUID_EDX, 11, 0x80000007, 0 }, { X86_FEATURE_MBA, CPUID_EBX, 6, 0x80000008, 0 }, + { X86_FEATURE_PERFMON_V2, CPUID_EAX, 0, 0x80000022, 0 }, { 0, 0, 0, 0, 0 } }; -- GitLab