[PATCH v3 11/11] KVM: selftests: Test AMD Guest PerfMonV2

From: Jinrong Liang
Date: Mon Aug 14 2023 - 07:52:41 EST


From: Jinrong Liang <cloudliang@xxxxxxxxxxx>

Add test case for AMD Guest PerfMonV2. Also test Intel
MSR_CORE_PERF_GLOBAL_STATUS and MSR_CORE_PERF_GLOBAL_OVF_CTRL.

Signed-off-by: Jinrong Liang <cloudliang@xxxxxxxxxxx>
---
.../kvm/x86_64/pmu_basic_functionality_test.c | 48 ++++++++++++++++++-
1 file changed, 46 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/kvm/x86_64/pmu_basic_functionality_test.c b/tools/testing/selftests/kvm/x86_64/pmu_basic_functionality_test.c
index cb2a7ad5c504..02bd1fe3900b 100644
--- a/tools/testing/selftests/kvm/x86_64/pmu_basic_functionality_test.c
+++ b/tools/testing/selftests/kvm/x86_64/pmu_basic_functionality_test.c
@@ -58,7 +58,9 @@ static uint64_t run_vcpu(struct kvm_vcpu *vcpu, uint64_t *ucall_arg)

static void guest_measure_loop(uint64_t event_code)
{
+ uint64_t global_ovf_ctrl_msr, global_status_msr, global_ctrl_msr;
uint8_t nr_gp_counters, pmu_version = 1;
+ uint8_t gp_counter_bit_width = 48;
uint64_t event_sel_msr;
uint32_t counter_msr;
unsigned int i;
@@ -68,6 +70,12 @@ static void guest_measure_loop(uint64_t event_code)
pmu_version = this_cpu_property(X86_PROPERTY_PMU_VERSION);
event_sel_msr = MSR_P6_EVNTSEL0;

+ if (pmu_version > 1) {
+ global_ovf_ctrl_msr = MSR_CORE_PERF_GLOBAL_OVF_CTRL;
+ global_status_msr = MSR_CORE_PERF_GLOBAL_STATUS;
+ global_ctrl_msr = MSR_CORE_PERF_GLOBAL_CTRL;
+ }
+
if (rdmsr(MSR_IA32_PERF_CAPABILITIES) & PMU_CAP_FW_WRITES)
counter_msr = MSR_IA32_PMC0;
else
@@ -76,6 +84,17 @@ static void guest_measure_loop(uint64_t event_code)
nr_gp_counters = AMD64_NR_COUNTERS;
event_sel_msr = MSR_K7_EVNTSEL0;
counter_msr = MSR_K7_PERFCTR0;
+
+ if (this_cpu_has(X86_FEATURE_AMD_PMU_EXT_CORE) &&
+ this_cpu_has(X86_FEATURE_AMD_PERFMON_V2)) {
+ nr_gp_counters = this_cpu_property(X86_PROPERTY_AMD_PMU_NR_CORE_COUNTERS);
+ global_ovf_ctrl_msr = MSR_AMD64_PERF_CNTR_GLOBAL_STATUS_CLR;
+ global_status_msr = MSR_AMD64_PERF_CNTR_GLOBAL_STATUS;
+ global_ctrl_msr = MSR_AMD64_PERF_CNTR_GLOBAL_CTL;
+ event_sel_msr = MSR_F15H_PERF_CTL0;
+ counter_msr = MSR_F15H_PERF_CTR0;
+ pmu_version = 2;
+ }
}

for (i = 0; i < nr_gp_counters; i++) {
@@ -84,14 +103,39 @@ static void guest_measure_loop(uint64_t event_code)
ARCH_PERFMON_EVENTSEL_ENABLE | event_code);

if (pmu_version > 1) {
- wrmsr(MSR_CORE_PERF_GLOBAL_CTRL, BIT_ULL(i));
+ wrmsr(global_ctrl_msr, BIT_ULL(i));
__asm__ __volatile__("loop ." : "+c"((int){NUM_BRANCHES}));
- wrmsr(MSR_CORE_PERF_GLOBAL_CTRL, 0);
+ wrmsr(global_ctrl_msr, 0);
GUEST_SYNC(_rdpmc(i));
} else {
__asm__ __volatile__("loop ." : "+c"((int){NUM_BRANCHES}));
GUEST_SYNC(_rdpmc(i));
}
+
+ if (pmu_version > 1 && _rdpmc(i)) {
+ wrmsr(global_ctrl_msr, 0);
+ wrmsr(counter_msr + i, 0);
+ __asm__ __volatile__("loop ." : "+c"((int){NUM_BRANCHES}));
+ GUEST_ASSERT(!_rdpmc(i));
+
+ wrmsr(global_ctrl_msr, BIT_ULL(i));
+ __asm__ __volatile__("loop ." : "+c"((int){NUM_BRANCHES}));
+ GUEST_ASSERT(_rdpmc(i));
+
+ if (host_cpu_is_intel)
+ gp_counter_bit_width =
+ this_cpu_property(X86_PROPERTY_PMU_GP_COUNTERS_BIT_WIDTH);
+
+ wrmsr(global_ctrl_msr, 0);
+ wrmsr(counter_msr + i, (1ULL << gp_counter_bit_width) - 2);
+ wrmsr(global_ctrl_msr, BIT_ULL(i));
+ __asm__ __volatile__("loop ." : "+c"((int){NUM_BRANCHES}));
+ GUEST_ASSERT(rdmsr(global_status_msr) & BIT_ULL(i));
+
+ wrmsr(global_ctrl_msr, 0);
+ wrmsr(global_ovf_ctrl_msr, BIT_ULL(i));
+ GUEST_ASSERT(!(rdmsr(global_status_msr) & BIT_ULL(i)));
+ }
}

if (host_cpu_is_amd || pmu_version < 2)
--
2.39.3