[PATCH 0/4] Support Perf Extension on AMD KVM guests

From: Janakarajan Natarajan
Date: Wed Nov 01 2017 - 12:20:47 EST


This patchset adds support for Perf Extension on AMD KVM guests.

When perf runs on a guest with family = 15h || 17h, the MSRs that are
accessed, when the Perf Extension flag is made available, differ from
the existing K7 MSRs. The accesses are to the AMD Core Performance
Extension counters which provide 2 extra counters and new MSRs for both
the event select and counter registers.

Routines are introduced to choose the proper MSR based on the guest
family. Since the new event select and counter MSRs are interleaved
and K7 MSRs are contiguous, the logic to map them to the gp_counters[]
is changed.

Additionally, a fix is provided for CPUID_8000_0001_ECX in reverse_cpuid[]
to change the CPUID function from 0xc0000001 to 0x80000001.

This patchset has been tested with Family 17h and Opteron G1 guests.

Janakarajan Natarajan (4):
x86/kvm/cpuid: Fix CPUID function for word 6 (80000001_ECX)
Add AMD Core Perf Extension MSRs
Add support for AMD Core Perf Extension in guest
Expose AMD Core Perf Extension flag to guests

arch/x86/include/asm/msr-index.h | 12 ++++
arch/x86/kvm/cpuid.c | 8 ++-
arch/x86/kvm/cpuid.h | 2 +-
arch/x86/kvm/pmu_amd.c | 133 ++++++++++++++++++++++++++++++++++-----
arch/x86/kvm/x86.c | 1 +
5 files changed, 140 insertions(+), 16 deletions(-)

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2.7.4