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KVM: selftests: Test if event filter meets expectations on fixed counters

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Add tests to cover that pmu event_filter works as expected when it's
applied to fixed performance counters, even if there is none fixed
counter exists (e.g. Intel guest pmu version=1 or AMD guest).

Signed-off-by: Jinrong Liang <cloudliang@tencent.com>
Reviewed-by: Isaku Yamahata <isaku.yamahata@intel.com>
Link: https://lore.kernel.org/r/20230810090945.16053-6-cloudliang@tencent.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
This commit is contained in:
Jinrong Liang 2023-08-10 17:09:44 +08:00 committed by Sean Christopherson
parent 86ab6af8b9
commit d4e3616682
1 changed files with 80 additions and 0 deletions
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80
tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c
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@ -27,6 +27,7 @@
#define ARCH_PERFMON_BRANCHES_RETIRED 5
#define NUM_BRANCHES 42
#define INTEL_PMC_IDX_FIXED 32
/* Matches KVM_PMU_EVENT_FILTER_MAX_EVENTS in pmu.c */
#define MAX_FILTER_EVENTS 300
@ -808,6 +809,84 @@ static void test_filter_ioctl(struct kvm_vcpu *vcpu)
TEST_ASSERT(!r, "Masking non-existent fixed counters should be allowed");
}
static void intel_run_fixed_counter_guest_code(uint8_t fixed_ctr_idx)
{
for (;;) {
wrmsr(MSR_CORE_PERF_GLOBAL_CTRL, 0);
wrmsr(MSR_CORE_PERF_FIXED_CTR0 + fixed_ctr_idx, 0);
/* Only OS_EN bit is enabled for fixed counter[idx]. */
wrmsr(MSR_CORE_PERF_FIXED_CTR_CTRL, BIT_ULL(4 * fixed_ctr_idx));
wrmsr(MSR_CORE_PERF_GLOBAL_CTRL,
BIT_ULL(INTEL_PMC_IDX_FIXED + fixed_ctr_idx));
__asm__ __volatile__("loop ." : "+c"((int){NUM_BRANCHES}));
wrmsr(MSR_CORE_PERF_GLOBAL_CTRL, 0);
GUEST_SYNC(rdmsr(MSR_CORE_PERF_FIXED_CTR0 + fixed_ctr_idx));
}
}
static uint64_t test_with_fixed_counter_filter(struct kvm_vcpu *vcpu,
uint32_t action, uint32_t bitmap)
{
struct __kvm_pmu_event_filter f = {
.action = action,
.fixed_counter_bitmap = bitmap,
};
set_pmu_event_filter(vcpu, &f);
return run_vcpu_to_sync(vcpu);
}
static void __test_fixed_counter_bitmap(struct kvm_vcpu *vcpu, uint8_t idx,
uint8_t nr_fixed_counters)
{
unsigned int i;
uint32_t bitmap;
uint64_t count;
TEST_ASSERT(nr_fixed_counters < sizeof(bitmap) * 8,
"Invalid nr_fixed_counters");
/*
* Check the fixed performance counter can count normally when KVM
* userspace doesn't set any pmu filter.
*/
count = run_vcpu_to_sync(vcpu);
TEST_ASSERT(count, "Unexpected count value: %ld\n", count);
for (i = 0; i < BIT(nr_fixed_counters); i++) {
bitmap = BIT(i);
count = test_with_fixed_counter_filter(vcpu, KVM_PMU_EVENT_ALLOW,
bitmap);
TEST_ASSERT_EQ(!!count, !!(bitmap & BIT(idx)));
count = test_with_fixed_counter_filter(vcpu, KVM_PMU_EVENT_DENY,
bitmap);
TEST_ASSERT_EQ(!!count, !(bitmap & BIT(idx)));
}
}
static void test_fixed_counter_bitmap(void)
{
uint8_t nr_fixed_counters = kvm_cpu_property(X86_PROPERTY_PMU_NR_FIXED_COUNTERS);
struct kvm_vm *vm;
struct kvm_vcpu *vcpu;
uint8_t idx;
/*
* Check that pmu_event_filter works as expected when it's applied to
* fixed performance counters.
*/
for (idx = 0; idx < nr_fixed_counters; idx++) {
vm = vm_create_with_one_vcpu(&vcpu,
intel_run_fixed_counter_guest_code);
vcpu_args_set(vcpu, 1, idx);
__test_fixed_counter_bitmap(vcpu, idx, nr_fixed_counters);
kvm_vm_free(vm);
}
}
int main(int argc, char *argv[])
{
void (*guest_code)(void);
@ -851,6 +930,7 @@ int main(int argc, char *argv[])
kvm_vm_free(vm);
test_pmu_config_disable(guest_code);
test_fixed_counter_bitmap();
return 0;
}