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| author | Like Xu <likexu@tencent.com> | 2022-03-30 02:50:54 +0300 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2022-04-13 20:37:45 +0300 |
| commit | 1921f3aa9263977f6c31b1c3eb2814bff2e84a12 (patch) | |
| tree | c015e1b55f22311ab59645010b56c5bc42d5ce9f /arch/x86/include/asm/kvm-x86-pmu-ops.h | |
| parent | 34886e796c413273908b036df57cc9ae731badae (diff) | |
| download | linux-1921f3aa9263977f6c31b1c3eb2814bff2e84a12.tar.xz | |
KVM: x86: Use static calls to reduce kvm_pmu_ops overhead
Use static calls to improve kvm_pmu_ops performance, following the same
pattern and naming scheme used by kvm-x86-ops.h.
Here are the worst fenced_rdtsc() cycles numbers for the kvm_pmu_ops
functions that is most often called (up to 7 digits of calls) when running
a single perf test case in a guest on an ICX 2.70GHz host (mitigations=on):
| legacy | static call
------------------------------------------------------------
.pmc_idx_to_pmc | 1304840 | 994872 (+23%)
.pmc_is_enabled | 978670 | 1011750 (-3%)
.msr_idx_to_pmc | 47828 | 41690 (+12%)
.is_valid_msr | 28786 | 30108 (-4%)
Signed-off-by: Like Xu <likexu@tencent.com>
[sean: Handle static call updates in pmu.c, tweak changelog]
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220329235054.3534728-5-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/include/asm/kvm-x86-pmu-ops.h')
| -rw-r--r-- | arch/x86/include/asm/kvm-x86-pmu-ops.h | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/arch/x86/include/asm/kvm-x86-pmu-ops.h b/arch/x86/include/asm/kvm-x86-pmu-ops.h new file mode 100644 index 000000000000..fdfd8e06fee6 --- /dev/null +++ b/arch/x86/include/asm/kvm-x86-pmu-ops.h @@ -0,0 +1,31 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#if !defined(KVM_X86_PMU_OP) || !defined(KVM_X86_PMU_OP_OPTIONAL) +BUILD_BUG_ON(1) +#endif + +/* + * KVM_X86_PMU_OP() and KVM_X86_PMU_OP_OPTIONAL() are used to help generate + * both DECLARE/DEFINE_STATIC_CALL() invocations and + * "static_call_update()" calls. + * + * KVM_X86_PMU_OP_OPTIONAL() can be used for those functions that can have + * a NULL definition, for example if "static_call_cond()" will be used + * at the call sites. + */ +KVM_X86_PMU_OP(pmc_perf_hw_id) +KVM_X86_PMU_OP(pmc_is_enabled) +KVM_X86_PMU_OP(pmc_idx_to_pmc) +KVM_X86_PMU_OP(rdpmc_ecx_to_pmc) +KVM_X86_PMU_OP(msr_idx_to_pmc) +KVM_X86_PMU_OP(is_valid_rdpmc_ecx) +KVM_X86_PMU_OP(is_valid_msr) +KVM_X86_PMU_OP(get_msr) +KVM_X86_PMU_OP(set_msr) +KVM_X86_PMU_OP(refresh) +KVM_X86_PMU_OP(init) +KVM_X86_PMU_OP(reset) +KVM_X86_PMU_OP_OPTIONAL(deliver_pmi) +KVM_X86_PMU_OP_OPTIONAL(cleanup) + +#undef KVM_X86_PMU_OP +#undef KVM_X86_PMU_OP_OPTIONAL |