From de527b1daf69a41a265f48ad7bb9207ca7b7d29b Mon Sep 17 00:00:00 2001 From: Jinrong Liang Date: Thu, 10 Aug 2023 17:09:42 +0800 Subject: [PATCH] KVM: selftests: Introduce "struct __kvm_pmu_event_filter" to manipulate filter Add custom "__kvm_pmu_event_filter" structure to improve pmu event filter settings. Simplifies event filter setup by organizing event filter parameters in a cleaner, more organized way. Alternatively, selftests could use a struct overlay ala vcpu_set_msr() to avoid dynamically allocating the array: struct { struct kvm_msrs header; struct kvm_msr_entry entry; } buffer = {}; memset(&buffer, 0, sizeof(buffer)); buffer.header.nmsrs = 1; buffer.entry.index = msr_index; buffer.entry.data = msr_value; but the extra layer added by the nested structs is counterproductive to writing efficient, clean code. Suggested-by: Sean Christopherson Signed-off-by: Jinrong Liang Link: https://lore.kernel.org/r/20230810090945.16053-4-cloudliang@tencent.com [sean: massage changelog to explain alternative] Signed-off-by: Sean Christopherson --- .../selftests/kvm/x86_64/pmu_event_filter_test.c | 182 ++++++++++----------- 1 file changed, 90 insertions(+), 92 deletions(-) diff --git a/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c b/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c index 5ac05e64..fcb6cf9 100644 --- a/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c +++ b/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c @@ -28,6 +28,10 @@ #define NUM_BRANCHES 42 +/* Matches KVM_PMU_EVENT_FILTER_MAX_EVENTS in pmu.c */ +#define MAX_FILTER_EVENTS 300 +#define MAX_TEST_EVENTS 10 + /* * This is how the event selector and unit mask are stored in an AMD * core performance event-select register. Intel's format is similar, @@ -69,21 +73,33 @@ #define INST_RETIRED EVENT(0xc0, 0) +struct __kvm_pmu_event_filter { + __u32 action; + __u32 nevents; + __u32 fixed_counter_bitmap; + __u32 flags; + __u32 pad[4]; + __u64 events[MAX_FILTER_EVENTS]; +}; + /* * This event list comprises Intel's eight architectural events plus * AMD's "retired branch instructions" for Zen[123] (and possibly * other AMD CPUs). */ -static const uint64_t event_list[] = { - EVENT(0x3c, 0), - INST_RETIRED, - EVENT(0x3c, 1), - EVENT(0x2e, 0x4f), - EVENT(0x2e, 0x41), - EVENT(0xc4, 0), - EVENT(0xc5, 0), - EVENT(0xa4, 1), - AMD_ZEN_BR_RETIRED, +static const struct __kvm_pmu_event_filter base_event_filter = { + .nevents = ARRAY_SIZE(base_event_filter.events), + .events = { + EVENT(0x3c, 0), + INST_RETIRED, + EVENT(0x3c, 1), + EVENT(0x2e, 0x4f), + EVENT(0x2e, 0x41), + EVENT(0xc4, 0), + EVENT(0xc5, 0), + EVENT(0xa4, 1), + AMD_ZEN_BR_RETIRED, + }, }; struct { @@ -225,47 +241,11 @@ static bool sanity_check_pmu(struct kvm_vcpu *vcpu) return !r; } -static struct kvm_pmu_event_filter *alloc_pmu_event_filter(uint32_t nevents) -{ - struct kvm_pmu_event_filter *f; - int size = sizeof(*f) + nevents * sizeof(f->events[0]); - - f = malloc(size); - TEST_ASSERT(f, "Out of memory"); - memset(f, 0, size); - f->nevents = nevents; - return f; -} - - -static struct kvm_pmu_event_filter * -create_pmu_event_filter(const uint64_t event_list[], int nevents, - uint32_t action, uint32_t flags) -{ - struct kvm_pmu_event_filter *f; - int i; - - f = alloc_pmu_event_filter(nevents); - f->action = action; - f->flags = flags; - for (i = 0; i < nevents; i++) - f->events[i] = event_list[i]; - - return f; -} - -static struct kvm_pmu_event_filter *event_filter(uint32_t action) -{ - return create_pmu_event_filter(event_list, - ARRAY_SIZE(event_list), - action, 0); -} - /* * Remove the first occurrence of 'event' (if any) from the filter's * event list. */ -static void remove_event(struct kvm_pmu_event_filter *f, uint64_t event) +static void remove_event(struct __kvm_pmu_event_filter *f, uint64_t event) { bool found = false; int i; @@ -313,66 +293,73 @@ static void test_without_filter(struct kvm_vcpu *vcpu) } static void test_with_filter(struct kvm_vcpu *vcpu, - struct kvm_pmu_event_filter *f) + struct __kvm_pmu_event_filter *__f) { + struct kvm_pmu_event_filter *f = (void *)__f; + vm_ioctl(vcpu->vm, KVM_SET_PMU_EVENT_FILTER, f); run_vcpu_and_sync_pmc_results(vcpu); } static void test_amd_deny_list(struct kvm_vcpu *vcpu) { - uint64_t event = EVENT(0x1C2, 0); - struct kvm_pmu_event_filter *f; + struct __kvm_pmu_event_filter f = { + .action = KVM_PMU_EVENT_DENY, + .nevents = 1, + .events = { + EVENT(0x1C2, 0), + }, + }; - f = create_pmu_event_filter(&event, 1, KVM_PMU_EVENT_DENY, 0); - test_with_filter(vcpu, f); - free(f); + test_with_filter(vcpu, &f); ASSERT_PMC_COUNTING_INSTRUCTIONS(); } static void test_member_deny_list(struct kvm_vcpu *vcpu) { - struct kvm_pmu_event_filter *f = event_filter(KVM_PMU_EVENT_DENY); + struct __kvm_pmu_event_filter f = base_event_filter; - test_with_filter(vcpu, f); - free(f); + f.action = KVM_PMU_EVENT_DENY; + test_with_filter(vcpu, &f); ASSERT_PMC_NOT_COUNTING_INSTRUCTIONS(); } static void test_member_allow_list(struct kvm_vcpu *vcpu) { - struct kvm_pmu_event_filter *f = event_filter(KVM_PMU_EVENT_ALLOW); + struct __kvm_pmu_event_filter f = base_event_filter; - test_with_filter(vcpu, f); - free(f); + f.action = KVM_PMU_EVENT_ALLOW; + test_with_filter(vcpu, &f); ASSERT_PMC_COUNTING_INSTRUCTIONS(); } static void test_not_member_deny_list(struct kvm_vcpu *vcpu) { - struct kvm_pmu_event_filter *f = event_filter(KVM_PMU_EVENT_DENY); + struct __kvm_pmu_event_filter f = base_event_filter; - remove_event(f, INST_RETIRED); - remove_event(f, INTEL_BR_RETIRED); - remove_event(f, AMD_ZEN_BR_RETIRED); - test_with_filter(vcpu, f); - free(f); + f.action = KVM_PMU_EVENT_DENY; + + remove_event(&f, INST_RETIRED); + remove_event(&f, INTEL_BR_RETIRED); + remove_event(&f, AMD_ZEN_BR_RETIRED); + test_with_filter(vcpu, &f); ASSERT_PMC_COUNTING_INSTRUCTIONS(); } static void test_not_member_allow_list(struct kvm_vcpu *vcpu) { - struct kvm_pmu_event_filter *f = event_filter(KVM_PMU_EVENT_ALLOW); + struct __kvm_pmu_event_filter f = base_event_filter; + + f.action = KVM_PMU_EVENT_ALLOW; - remove_event(f, INST_RETIRED); - remove_event(f, INTEL_BR_RETIRED); - remove_event(f, AMD_ZEN_BR_RETIRED); - test_with_filter(vcpu, f); - free(f); + remove_event(&f, INST_RETIRED); + remove_event(&f, INTEL_BR_RETIRED); + remove_event(&f, AMD_ZEN_BR_RETIRED); + test_with_filter(vcpu, &f); ASSERT_PMC_NOT_COUNTING_INSTRUCTIONS(); } @@ -567,19 +554,16 @@ static void run_masked_events_test(struct kvm_vcpu *vcpu, const uint64_t masked_events[], const int nmasked_events) { - struct kvm_pmu_event_filter *f; + struct __kvm_pmu_event_filter f = { + .nevents = nmasked_events, + .action = KVM_PMU_EVENT_ALLOW, + .flags = KVM_PMU_EVENT_FLAG_MASKED_EVENTS, + }; - f = create_pmu_event_filter(masked_events, nmasked_events, - KVM_PMU_EVENT_ALLOW, - KVM_PMU_EVENT_FLAG_MASKED_EVENTS); - test_with_filter(vcpu, f); - free(f); + memcpy(f.events, masked_events, sizeof(uint64_t) * nmasked_events); + test_with_filter(vcpu, &f); } -/* Matches KVM_PMU_EVENT_FILTER_MAX_EVENTS in pmu.c */ -#define MAX_FILTER_EVENTS 300 -#define MAX_TEST_EVENTS 10 - #define ALLOW_LOADS BIT(0) #define ALLOW_STORES BIT(1) #define ALLOW_LOADS_STORES BIT(2) @@ -751,17 +735,27 @@ static void test_masked_events(struct kvm_vcpu *vcpu) run_masked_events_tests(vcpu, events, nevents); } -static int run_filter_test(struct kvm_vcpu *vcpu, const uint64_t *events, - int nevents, uint32_t flags) +static int set_pmu_event_filter(struct kvm_vcpu *vcpu, + struct __kvm_pmu_event_filter *__f) { - struct kvm_pmu_event_filter *f; - int r; + struct kvm_pmu_event_filter *f = (void *)__f; - f = create_pmu_event_filter(events, nevents, KVM_PMU_EVENT_ALLOW, flags); - r = __vm_ioctl(vcpu->vm, KVM_SET_PMU_EVENT_FILTER, f); - free(f); + return __vm_ioctl(vcpu->vm, KVM_SET_PMU_EVENT_FILTER, f); +} + +static int set_pmu_single_event_filter(struct kvm_vcpu *vcpu, uint64_t event, + uint32_t flags, uint32_t action) +{ + struct __kvm_pmu_event_filter f = { + .nevents = 1, + .flags = flags, + .action = action, + .events = { + event, + }, + }; - return r; + return set_pmu_event_filter(vcpu, &f); } static void test_filter_ioctl(struct kvm_vcpu *vcpu) @@ -773,14 +767,18 @@ static void test_filter_ioctl(struct kvm_vcpu *vcpu) * Unfortunately having invalid bits set in event data is expected to * pass when flags == 0 (bits other than eventsel+umask). */ - r = run_filter_test(vcpu, &e, 1, 0); + r = set_pmu_single_event_filter(vcpu, e, 0, KVM_PMU_EVENT_ALLOW); TEST_ASSERT(r == 0, "Valid PMU Event Filter is failing"); - r = run_filter_test(vcpu, &e, 1, KVM_PMU_EVENT_FLAG_MASKED_EVENTS); + r = set_pmu_single_event_filter(vcpu, e, + KVM_PMU_EVENT_FLAG_MASKED_EVENTS, + KVM_PMU_EVENT_ALLOW); TEST_ASSERT(r != 0, "Invalid PMU Event Filter is expected to fail"); e = KVM_PMU_ENCODE_MASKED_ENTRY(0xff, 0xff, 0xff, 0xf); - r = run_filter_test(vcpu, &e, 1, KVM_PMU_EVENT_FLAG_MASKED_EVENTS); + r = set_pmu_single_event_filter(vcpu, e, + KVM_PMU_EVENT_FLAG_MASKED_EVENTS, + KVM_PMU_EVENT_ALLOW); TEST_ASSERT(r == 0, "Valid PMU Event Filter is failing"); } -- 2.7.4