3 Commits

Author	SHA1	Message	Date
Like Xu	13afa29ae4	KVM: x86/pmu: Provide Intel PMU's pmc_is_enabled() as generic x86 code ... Move the Intel PMU implementation of pmc_is_enabled() to common x86 code as pmc_is_globally_enabled(), and drop AMD's implementation. AMD PMU currently supports only v1, and thus not PERF_GLOBAL_CONTROL, thus the semantics for AMD are unchanged. And when support for AMD PMU v2 comes along, the common behavior will also Just Work. Signed-off-by: Like Xu <likexu@tencent.com> Co-developed-by: Sean Christopherson <seanjc@google.com> Link: https://lore.kernel.org/r/20230603011058.1038821-6-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>	2023-06-06 17:31:44 -07:00
Like Xu	7aadaa988c	KVM: x86/pmu: Drop amd_event_mapping[] in the KVM context ... All gp or fixed counters have been reprogrammed using PERF_TYPE_RAW, which means that the table that maps perf_hw_id to event select values is no longer useful, at least for AMD. For Intel, the logic to check if the pmu event reported by Intel cpuid is not available is still required, in which case pmc_perf_hw_id() could be renamed to hw_event_is_unavail() and a bool value is returned to replace the semantics of "PERF_COUNT_HW_MAX+1". Signed-off-by: Like Xu <likexu@tencent.com> Message-Id: <20220518132512.37864-12-likexu@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>	2022-06-08 04:49:06 -04:00
Like Xu	1921f3aa92	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>	2022-04-13 13:37:45 -04:00