[PATCH 5/9] KVM: selftests: Test AMD PMU performance counters basic functions

From: Jinrong Liang
Date: Tue Nov 21 2023 - 07:42:55 EST


From: Jinrong Liang <cloudliang@xxxxxxxxxxx>

Add tests to check AMD PMU performance counters basic functions.

Signed-off-by: Jinrong Liang <cloudliang@xxxxxxxxxxx>
---
.../selftests/kvm/x86_64/pmu_counters_test.c | 84 +++++++++++++++++--
1 file changed, 75 insertions(+), 9 deletions(-)

diff --git a/tools/testing/selftests/kvm/x86_64/pmu_counters_test.c b/tools/testing/selftests/kvm/x86_64/pmu_counters_test.c
index efd8c61e1c16..3c4081a508b0 100644
--- a/tools/testing/selftests/kvm/x86_64/pmu_counters_test.c
+++ b/tools/testing/selftests/kvm/x86_64/pmu_counters_test.c
@@ -21,6 +21,8 @@
#define NUM_INSNS_RETIRED (NUM_BRANCHES + NUM_EXTRA_INSNS)

#define PMI_VECTOR 0x20
+#define AMD64_NR_COUNTERS 4
+#define AMD64_NR_COUNTERS_CORE 6

static uint8_t kvm_pmu_version;
static bool kvm_has_perf_caps;
@@ -411,7 +413,6 @@ static void guest_rd_wr_counters(uint32_t base_msr, uint8_t nr_possible_counters
rdpmc_idx = i;
if (base_msr == MSR_CORE_PERF_FIXED_CTR0)
rdpmc_idx |= INTEL_RDPMC_FIXED;
-
guest_test_rdpmc(rdpmc_idx, expect_success, expected_val);

/*
@@ -421,7 +422,6 @@ static void guest_rd_wr_counters(uint32_t base_msr, uint8_t nr_possible_counters
*/
GUEST_ASSERT(!expect_success || !pmu_has_fast_mode);
rdpmc_idx |= INTEL_RDPMC_FAST;
-
guest_test_rdpmc(rdpmc_idx, false, -1ull);

vector = wrmsr_safe(msr, 0);
@@ -701,19 +701,85 @@ static void test_intel_counters(void)
}
}

+static void set_amd_counters(uint8_t *nr_amd_ounters, uint64_t *ctrl_msr,
+ uint32_t *pmc_msr, uint8_t *flag)
+{
+ if (this_cpu_has(X86_FEATURE_PERFMON_V2)) {
+ *nr_amd_ounters = this_cpu_property(X86_PROPERTY_PMU_NR_CORE_COUNTERS);
+ *ctrl_msr = MSR_F15H_PERF_CTL0;
+ *pmc_msr = MSR_F15H_PERF_CTR0;
+ *flag = 2;
+ } else if (this_cpu_has(X86_FEATURE_PERFCTR_CORE)) {
+ *nr_amd_ounters = AMD64_NR_COUNTERS_CORE;
+ *ctrl_msr = MSR_F15H_PERF_CTL0;
+ *pmc_msr = MSR_F15H_PERF_CTR0;
+ *flag = 2;
+ } else {
+ *nr_amd_ounters = AMD64_NR_COUNTERS;
+ *ctrl_msr = MSR_K7_EVNTSEL0;
+ *pmc_msr = MSR_K7_PERFCTR0;
+ *flag = 1;
+ }
+}
+
+static void guest_test_amd_counters(void)
+{
+ bool guest_pmu_is_perfmonv2 = this_cpu_has(X86_FEATURE_PERFMON_V2);
+ uint8_t nr_amd_counters, flag;
+ uint64_t ctrl_msr;
+ unsigned int i, j;
+ uint32_t pmc_msr;
+
+ set_amd_counters(&nr_amd_counters, &ctrl_msr, &pmc_msr, &flag);
+
+ for (i = 0; i < nr_amd_counters; i++) {
+ for (j = 0; j < NR_AMD_ZEN_EVENTS; j++) {
+ wrmsr(pmc_msr + i * flag, 0);
+ wrmsr(ctrl_msr + i * flag, ARCH_PERFMON_EVENTSEL_OS |
+ ARCH_PERFMON_EVENTSEL_ENABLE | amd_pmu_zen_events[j]);
+
+ if (guest_pmu_is_perfmonv2)
+ wrmsr(MSR_AMD64_PERF_CNTR_GLOBAL_CTL, BIT_ULL(i));
+
+ __asm__ __volatile__("loop ." : "+c"((int){NUM_BRANCHES}));
+
+ GUEST_ASSERT(rdmsr(pmc_msr + i * flag));
+ }
+ }
+
+ GUEST_DONE();
+}
+
+static void test_amd_zen_events(void)
+{
+ struct kvm_vcpu *vcpu;
+ struct kvm_vm *vm;
+
+ vm = pmu_vm_create_with_one_vcpu(&vcpu, guest_test_amd_counters);
+
+ run_vcpu(vcpu);
+ kvm_vm_free(vm);
+}
+
int main(int argc, char *argv[])
{
TEST_REQUIRE(kvm_is_pmu_enabled());

- TEST_REQUIRE(host_cpu_is_intel);
- TEST_REQUIRE(kvm_cpu_has_p(X86_PROPERTY_PMU_VERSION));
- TEST_REQUIRE(kvm_cpu_property(X86_PROPERTY_PMU_VERSION) > 0);
+ if (host_cpu_is_intel) {
+ TEST_REQUIRE(kvm_cpu_has_p(X86_PROPERTY_PMU_VERSION));
+ TEST_REQUIRE(kvm_cpu_property(X86_PROPERTY_PMU_VERSION) > 0);
+ TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_PDCM));

- kvm_pmu_version = kvm_cpu_property(X86_PROPERTY_PMU_VERSION);
- kvm_has_perf_caps = kvm_cpu_has(X86_FEATURE_PDCM);
- is_forced_emulation_enabled = kvm_is_forced_emulation_enabled();
+ kvm_pmu_version = kvm_cpu_property(X86_PROPERTY_PMU_VERSION);
+ kvm_has_perf_caps = kvm_cpu_has(X86_FEATURE_PDCM);
+ is_forced_emulation_enabled = kvm_is_forced_emulation_enabled();

- test_intel_counters();
+ test_intel_counters();
+ } else if (host_cpu_is_amd) {
+ test_amd_zen_events();
+ } else {
+ TEST_FAIL("Unknown CPU vendor");
+ }

return 0;
}
--
2.39.3