From 37f4e79c43e5750e75b3de8726b4c21bae6ab7aa Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Fri, 10 Mar 2023 16:46:11 -0800 Subject: [PATCH] KVM: selftests: Test all fungible features in PERF_CAPABILITIES Verify that userspace can set all fungible features in PERF_CAPABILITIES. Drop the now unused #define of the "full-width writes" flag. Link: https://lore.kernel.org/r/20230311004618.920745-15-seanjc@google.com Signed-off-by: Sean Christopherson --- .../selftests/kvm/x86_64/vmx_pmu_caps_test.c | 29 ++++++++++++++++++---- 1 file changed, 24 insertions(+), 5 deletions(-) diff --git a/tools/testing/selftests/kvm/x86_64/vmx_pmu_caps_test.c b/tools/testing/selftests/kvm/x86_64/vmx_pmu_caps_test.c index f7a27b5..2647282 100644 --- a/tools/testing/selftests/kvm/x86_64/vmx_pmu_caps_test.c +++ b/tools/testing/selftests/kvm/x86_64/vmx_pmu_caps_test.c @@ -14,10 +14,11 @@ #define _GNU_SOURCE /* for program_invocation_short_name */ #include +#include + #include "kvm_util.h" #include "vmx.h" -#define PMU_CAP_FW_WRITES (1ULL << 13) #define PMU_CAP_LBR_FMT 0x3f union perf_capabilities { @@ -36,6 +37,18 @@ union perf_capabilities { u64 capabilities; }; +/* + * The LBR format and most PEBS features are immutable, all other features are + * fungible (if supported by the host and KVM). + */ +static const union perf_capabilities immutable_caps = { + .lbr_format = -1, + .pebs_trap = 1, + .pebs_arch_reg = 1, + .pebs_format = -1, + .pebs_baseline = 1, +}; + static void guest_code(void) { wrmsr(MSR_IA32_PERF_CAPABILITIES, PMU_CAP_LBR_FMT); @@ -58,15 +71,22 @@ static void test_basic_perf_capabilities(union perf_capabilities host_cap) static void test_fungible_perf_capabilities(union perf_capabilities host_cap) { + const uint64_t fungible_caps = host_cap.capabilities & ~immutable_caps.capabilities; + struct kvm_vcpu *vcpu; struct kvm_vm *vm = vm_create_with_one_vcpu(&vcpu, guest_code); + int bit; - /* testcase 1, set capabilities when we have PDCM bit */ - vcpu_set_msr(vcpu, MSR_IA32_PERF_CAPABILITIES, PMU_CAP_FW_WRITES); + for_each_set_bit(bit, &fungible_caps, 64) { + vcpu_set_msr(vcpu, MSR_IA32_PERF_CAPABILITIES, BIT_ULL(bit)); + vcpu_set_msr(vcpu, MSR_IA32_PERF_CAPABILITIES, + host_cap.capabilities & ~BIT_ULL(bit)); + } + vcpu_set_msr(vcpu, MSR_IA32_PERF_CAPABILITIES, host_cap.capabilities); /* check whatever we write with KVM_SET_MSR is _not_ modified */ vcpu_run(vcpu); - ASSERT_EQ(vcpu_get_msr(vcpu, MSR_IA32_PERF_CAPABILITIES), PMU_CAP_FW_WRITES); + ASSERT_EQ(vcpu_get_msr(vcpu, MSR_IA32_PERF_CAPABILITIES), host_cap.capabilities); kvm_vm_free(vm); } @@ -102,7 +122,6 @@ int main(int argc, char *argv[]) TEST_REQUIRE(kvm_cpu_property(X86_PROPERTY_PMU_VERSION) > 0); host_cap.capabilities = kvm_get_feature_msr(MSR_IA32_PERF_CAPABILITIES); - host_cap.capabilities &= (PMU_CAP_FW_WRITES | PMU_CAP_LBR_FMT); TEST_ASSERT(host_cap.full_width_write, "Full-width writes should always be supported"); -- 2.7.4