[PATCH v7 08/19] KVM: selftests: Add pmu.h and lib/pmu.c for common PMU assets

Sean Christopherson
2023-11-08T00:31:56Z

From: Jinrong Liang <cloudliang@tencent.com>

Add a PMU library for x86 selftests to help eliminate open-coded event
encodings, and to reduce the amount of copy+paste between PMU selftests.

Use the new common macro definitions in the existing PMU event filter test.

Cc: Aaron Lewis <aaronlewis@google.com>
Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Jinrong Liang <cloudliang@tencent.com>
Co-developed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
tools/testing/selftests/kvm/Makefile | 1 +
tools/testing/selftests/kvm/include/pmu.h | 95 ++++++++++++
tools/testing/selftests/kvm/lib/pmu.c | 31 ++++
.../kvm/x86_64/pmu_event_filter_test.c | 141 ++++++------------
4 files changed, 171 insertions(+), 97 deletions(-)
create mode 100644 tools/testing/selftests/kvm/include/pmu.h
create mode 100644 tools/testing/selftests/kvm/lib/pmu.c

diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index a5963ab9215b..44d8d022b023 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -32,6 +32,7 @@ LIBKVM += lib/guest_modes.c
LIBKVM += lib/io.c
LIBKVM += lib/kvm_util.c
LIBKVM += lib/memstress.c
+LIBKVM += lib/pmu.c
LIBKVM += lib/guest_sprintf.c
LIBKVM += lib/rbtree.c
LIBKVM += lib/sparsebit.c
diff --git a/tools/testing/selftests/kvm/include/pmu.h b/tools/testing/selftests/kvm/include/pmu.h
new file mode 100644
index 000000000000..2da59a9d98b3
--- /dev/null
+++ b/tools/testing/selftests/kvm/include/pmu.h
@@ -0,0 +1,95 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2023, Tencent, Inc.
+ */
+#ifndef SELFTEST_KVM_PMU_H
+#define SELFTEST_KVM_PMU_H
+
+#include <stdint.h>
+
+#define KVM_PMU_EVENT_FILTER_MAX_EVENTS 300
+
+/*
+ * Encode an eventsel+umask pair into event-select MSR format. Note, this is
+ * technically AMD's format, as Intel's format only supports 8 bits for the
+ * event selector, i.e. doesn't use bits 24:16 for the selector. But, OR-ing
+ * in '0' is a nop and won't clobber the CMASK.
+ */
+#define RAW_EVENT(eventsel, umask) (((eventsel & 0xf00UL) << 24) | \
+ ((eventsel) & 0xff) | \
+ ((umask) & 0xff) << 8)
+
+/*
+ * These are technically Intel's definitions, but except for CMASK (see above),
+ * AMD's layout is compatible with Intel's.
+ */
+#define ARCH_PERFMON_EVENTSEL_EVENT GENMASK_ULL(7, 0)
+#define ARCH_PERFMON_EVENTSEL_UMASK GENMASK_ULL(15, 8)
+#define ARCH_PERFMON_EVENTSEL_USR BIT_ULL(16)
+#define ARCH_PERFMON_EVENTSEL_OS BIT_ULL(17)
+#define ARCH_PERFMON_EVENTSEL_EDGE BIT_ULL(18)
+#define ARCH_PERFMON_EVENTSEL_PIN_CONTROL BIT_ULL(19)
+#define ARCH_PERFMON_EVENTSEL_INT BIT_ULL(20)
+#define ARCH_PERFMON_EVENTSEL_ANY BIT_ULL(21)
+#define ARCH_PERFMON_EVENTSEL_ENABLE BIT_ULL(22)
+#define ARCH_PERFMON_EVENTSEL_INV BIT_ULL(23)
+#define ARCH_PERFMON_EVENTSEL_CMASK GENMASK_ULL(31, 24)
+
+/* RDPMC offset for Fixed PMCs */
+#define FIXED_PMC_RDPMC_METRICS BIT_ULL(29)
+#define FIXED_PMC_RDPMC_BASE BIT_ULL(30)
+
+#define FIXED_PMC_GLOBAL_CTRL_ENABLE(_idx) BIT_ULL((32 + (_idx)))
+
+#define FIXED_PMC_KERNEL BIT_ULL(0)
+#define FIXED_PMC_USER BIT_ULL(1)
+#define FIXED_PMC_ANYTHREAD BIT_ULL(2)
+#define FIXED_PMC_ENABLE_PMI BIT_ULL(3)
+#define FIXED_PMC_NR_BITS 4
+#define FIXED_PMC_CTRL(_idx, _val) ((_val) << ((_idx) * FIXED_PMC_NR_BITS))
+
+#define PMU_CAP_FW_WRITES BIT_ULL(13)
+#define PMU_CAP_LBR_FMT 0x3f
+
+#define INTEL_ARCH_CPU_CYCLES RAW_EVENT(0x3c, 0x00)
+#define INTEL_ARCH_INSTRUCTIONS_RETIRED RAW_EVENT(0xc0, 0x00)
+#define INTEL_ARCH_REFERENCE_CYCLES RAW_EVENT(0x3c, 0x01)
+#define INTEL_ARCH_LLC_REFERENCES RAW_EVENT(0x2e, 0x4f)
+#define INTEL_ARCH_LLC_MISSES RAW_EVENT(0x2e, 0x41)
+#define INTEL_ARCH_BRANCHES_RETIRED RAW_EVENT(0xc4, 0x00)
+#define INTEL_ARCH_BRANCHES_MISPREDICTED RAW_EVENT(0xc5, 0x00)
+#define INTEL_ARCH_TOPDOWN_SLOTS RAW_EVENT(0xa4, 0x01)
+
+#define AMD_ZEN_CORE_CYCLES RAW_EVENT(0x76, 0x00)
+#define AMD_ZEN_INSTRUCTIONS_RETIRED RAW_EVENT(0xc0, 0x00)
+#define AMD_ZEN_BRANCHES_RETIRED RAW_EVENT(0xc2, 0x00)
+#define AMD_ZEN_BRANCHES_MISPREDICTED RAW_EVENT(0xc3, 0x00)
+
+/*
+ * Note! The order and thus the index of the architectural events matters as
+ * support for each event is enumerated via CPUID using the index of the event.
+ */
+enum intel_pmu_architectural_events {
+ INTEL_ARCH_CPU_CYCLES_INDEX,
+ INTEL_ARCH_INSTRUCTIONS_RETIRED_INDEX,
+ INTEL_ARCH_REFERENCE_CYCLES_INDEX,
+ INTEL_ARCH_LLC_REFERENCES_INDEX,
+ INTEL_ARCH_LLC_MISSES_INDEX,
+ INTEL_ARCH_BRANCHES_RETIRED_INDEX,
+ INTEL_ARCH_BRANCHES_MISPREDICTED_INDEX,
+ INTEL_ARCH_TOPDOWN_SLOTS_INDEX,
+ NR_INTEL_ARCH_EVENTS,
+};
+
+enum amd_pmu_zen_events {
+ AMD_ZEN_CORE_CYCLES_INDEX,
+ AMD_ZEN_INSTRUCTIONS_INDEX,
+ AMD_ZEN_BRANCHES_INDEX,
+ AMD_ZEN_BRANCH_MISSES_INDEX,
+ NR_AMD_ZEN_EVENTS,
+};
+
+extern const uint64_t intel_pmu_arch_events[];
+extern const uint64_t amd_pmu_zen_events[];
+
+#endif /* SELFTEST_KVM_PMU_H */
diff --git a/tools/testing/selftests/kvm/lib/pmu.c b/tools/testing/selftests/kvm/lib/pmu.c
new file mode 100644
index 000000000000..f31f0427c17c
--- /dev/null
+++ b/tools/testing/selftests/kvm/lib/pmu.c
@@ -0,0 +1,31 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2023, Tencent, Inc.
+ */
+
+#include <stdint.h>
+
+#include <linux/kernel.h>
+
+#include "kvm_util.h"
+#include "pmu.h"
+
+const uint64_t intel_pmu_arch_events[] = {
+ INTEL_ARCH_CPU_CYCLES,
+ INTEL_ARCH_INSTRUCTIONS_RETIRED,
+ INTEL_ARCH_REFERENCE_CYCLES,
+ INTEL_ARCH_LLC_REFERENCES,
+ INTEL_ARCH_LLC_MISSES,
+ INTEL_ARCH_BRANCHES_RETIRED,
+ INTEL_ARCH_BRANCHES_MISPREDICTED,
+ INTEL_ARCH_TOPDOWN_SLOTS,
+};
+kvm_static_assert(ARRAY_SIZE(intel_pmu_arch_events) == NR_INTEL_ARCH_EVENTS);
+
+const uint64_t amd_pmu_zen_events[] = {
+ AMD_ZEN_CORE_CYCLES,
+ AMD_ZEN_INSTRUCTIONS_RETIRED,
+ AMD_ZEN_BRANCHES_RETIRED,
+ AMD_ZEN_BRANCHES_MISPREDICTED,
+};
+kvm_static_assert(ARRAY_SIZE(amd_pmu_zen_events) == NR_AMD_ZEN_EVENTS);
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 283cc55597a4..7ec9fbed92e0 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
@@ -11,72 +11,18 @@
*/

#define _GNU_SOURCE /* for program_invocation_short_name */
-#include "test_util.h"
+
#include "kvm_util.h"
+#include "pmu.h"
#include "processor.h"
-
-/*
- * In lieu of copying perf_event.h into tools...
- */
-#define ARCH_PERFMON_EVENTSEL_OS (1ULL << 17)
-#define ARCH_PERFMON_EVENTSEL_ENABLE (1ULL << 22)
-
-/* End of stuff taken from perf_event.h. */
-
-/* Oddly, this isn't in perf_event.h. */
-#define ARCH_PERFMON_BRANCHES_RETIRED 5
+#include "test_util.h"

#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
#define MAX_TEST_EVENTS 10

#define PMU_EVENT_FILTER_INVALID_ACTION (KVM_PMU_EVENT_DENY + 1)
#define PMU_EVENT_FILTER_INVALID_FLAGS (KVM_PMU_EVENT_FLAGS_VALID_MASK << 1)
-#define PMU_EVENT_FILTER_INVALID_NEVENTS (MAX_FILTER_EVENTS + 1)
-
-/*
- * This is how the event selector and unit mask are stored in an AMD
- * core performance event-select register. Intel's format is similar,
- * but the event selector is only 8 bits.
- */
-#define EVENT(select, umask) ((select & 0xf00UL) << 24 | (select & 0xff) | \
- (umask & 0xff) << 8)
-
-/*
- * "Branch instructions retired", from the Intel SDM, volume 3,
- * "Pre-defined Architectural Performance Events."
- */
-
-#define INTEL_BR_RETIRED EVENT(0xc4, 0)
-
-/*
- * "Retired branch instructions", from Processor Programming Reference
- * (PPR) for AMD Family 17h Model 01h, Revision B1 Processors,
- * Preliminary Processor Programming Reference (PPR) for AMD Family
- * 17h Model 31h, Revision B0 Processors, and Preliminary Processor
- * Programming Reference (PPR) for AMD Family 19h Model 01h, Revision
- * B1 Processors Volume 1 of 2.
- */
-
-#define AMD_ZEN_BR_RETIRED EVENT(0xc2, 0)
-
-
-/*
- * "Retired instructions", from Processor Programming Reference
- * (PPR) for AMD Family 17h Model 01h, Revision B1 Processors,
- * Preliminary Processor Programming Reference (PPR) for AMD Family
- * 17h Model 31h, Revision B0 Processors, and Preliminary Processor
- * Programming Reference (PPR) for AMD Family 19h Model 01h, Revision
- * B1 Processors Volume 1 of 2.
- * --- and ---
- * "Instructions retired", from the Intel SDM, volume 3,
- * "Pre-defined Architectural Performance Events."
- */
-
-#define INST_RETIRED EVENT(0xc0, 0)
+#define PMU_EVENT_FILTER_INVALID_NEVENTS (KVM_PMU_EVENT_FILTER_MAX_EVENTS + 1)

struct __kvm_pmu_event_filter {
__u32 action;
@@ -84,26 +30,28 @@ struct __kvm_pmu_event_filter {
__u32 fixed_counter_bitmap;
__u32 flags;
__u32 pad[4];
- __u64 events[MAX_FILTER_EVENTS];
+ __u64 events[KVM_PMU_EVENT_FILTER_MAX_EVENTS];
};

/*
- * This event list comprises Intel's eight architectural events plus
- * AMD's "retired branch instructions" for Zen[123] (and possibly
- * other AMD CPUs).
+ * This event list comprises Intel's known architectural events, plus AMD's
+ * "retired branch instructions" for Zen1-Zen3 (and* possibly other AMD CPUs).
+ * Note, AMD and Intel use the same encoding for instructions retired.
*/
+kvm_static_assert(INTEL_ARCH_INSTRUCTIONS_RETIRED == AMD_ZEN_INSTRUCTIONS_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,
+ INTEL_ARCH_CPU_CYCLES,
+ INTEL_ARCH_INSTRUCTIONS_RETIRED,
+ INTEL_ARCH_REFERENCE_CYCLES,
+ INTEL_ARCH_LLC_REFERENCES,
+ INTEL_ARCH_LLC_MISSES,
+ INTEL_ARCH_BRANCHES_RETIRED,
+ INTEL_ARCH_BRANCHES_MISPREDICTED,
+ INTEL_ARCH_TOPDOWN_SLOTS,
+ AMD_ZEN_BRANCHES_RETIRED,
},
};

@@ -165,9 +113,9 @@ static void intel_guest_code(void)
for (;;) {
wrmsr(MSR_CORE_PERF_GLOBAL_CTRL, 0);
wrmsr(MSR_P6_EVNTSEL0, ARCH_PERFMON_EVENTSEL_ENABLE |
- ARCH_PERFMON_EVENTSEL_OS | INTEL_BR_RETIRED);
+ ARCH_PERFMON_EVENTSEL_OS | INTEL_ARCH_BRANCHES_RETIRED);
wrmsr(MSR_P6_EVNTSEL1, ARCH_PERFMON_EVENTSEL_ENABLE |
- ARCH_PERFMON_EVENTSEL_OS | INST_RETIRED);
+ ARCH_PERFMON_EVENTSEL_OS | INTEL_ARCH_INSTRUCTIONS_RETIRED);
wrmsr(MSR_CORE_PERF_GLOBAL_CTRL, 0x3);

run_and_measure_loop(MSR_IA32_PMC0);
@@ -189,9 +137,9 @@ static void amd_guest_code(void)
for (;;) {
wrmsr(MSR_K7_EVNTSEL0, 0);
wrmsr(MSR_K7_EVNTSEL0, ARCH_PERFMON_EVENTSEL_ENABLE |
- ARCH_PERFMON_EVENTSEL_OS | AMD_ZEN_BR_RETIRED);
+ ARCH_PERFMON_EVENTSEL_OS | AMD_ZEN_BRANCHES_RETIRED);
wrmsr(MSR_K7_EVNTSEL1, ARCH_PERFMON_EVENTSEL_ENABLE |
- ARCH_PERFMON_EVENTSEL_OS | INST_RETIRED);
+ ARCH_PERFMON_EVENTSEL_OS | AMD_ZEN_INSTRUCTIONS_RETIRED);

run_and_measure_loop(MSR_K7_PERFCTR0);
GUEST_SYNC(0);
@@ -312,7 +260,7 @@ static void test_amd_deny_list(struct kvm_vcpu *vcpu)
.action = KVM_PMU_EVENT_DENY,
.nevents = 1,
.events = {
- EVENT(0x1C2, 0),
+ RAW_EVENT(0x1C2, 0),
},
};

@@ -347,9 +295,9 @@ static void test_not_member_deny_list(struct kvm_vcpu *vcpu)

f.action = KVM_PMU_EVENT_DENY;

- remove_event(&f, INST_RETIRED);
- remove_event(&f, INTEL_BR_RETIRED);
- remove_event(&f, AMD_ZEN_BR_RETIRED);
+ remove_event(&f, INTEL_ARCH_INSTRUCTIONS_RETIRED);
+ remove_event(&f, INTEL_ARCH_BRANCHES_RETIRED);
+ remove_event(&f, AMD_ZEN_BRANCHES_RETIRED);
test_with_filter(vcpu, &f);

ASSERT_PMC_COUNTING_INSTRUCTIONS();
@@ -361,9 +309,9 @@ static void test_not_member_allow_list(struct kvm_vcpu *vcpu)

f.action = KVM_PMU_EVENT_ALLOW;

- remove_event(&f, INST_RETIRED);
- remove_event(&f, INTEL_BR_RETIRED);
- remove_event(&f, AMD_ZEN_BR_RETIRED);
+ remove_event(&f, INTEL_ARCH_INSTRUCTIONS_RETIRED);
+ remove_event(&f, INTEL_ARCH_BRANCHES_RETIRED);
+ remove_event(&f, AMD_ZEN_BRANCHES_RETIRED);
test_with_filter(vcpu, &f);

ASSERT_PMC_NOT_COUNTING_INSTRUCTIONS();
@@ -452,9 +400,9 @@ static bool use_amd_pmu(void)
* - Sapphire Rapids, Ice Lake, Cascade Lake, Skylake.
*/
#define MEM_INST_RETIRED 0xD0
-#define MEM_INST_RETIRED_LOAD EVENT(MEM_INST_RETIRED, 0x81)
-#define MEM_INST_RETIRED_STORE EVENT(MEM_INST_RETIRED, 0x82)
-#define MEM_INST_RETIRED_LOAD_STORE EVENT(MEM_INST_RETIRED, 0x83)
+#define MEM_INST_RETIRED_LOAD RAW_EVENT(MEM_INST_RETIRED, 0x81)
+#define MEM_INST_RETIRED_STORE RAW_EVENT(MEM_INST_RETIRED, 0x82)
+#define MEM_INST_RETIRED_LOAD_STORE RAW_EVENT(MEM_INST_RETIRED, 0x83)

static bool supports_event_mem_inst_retired(void)
{
@@ -486,9 +434,9 @@ static bool supports_event_mem_inst_retired(void)
* B1 Processors Volume 1 of 2.
*/
#define LS_DISPATCH 0x29
-#define LS_DISPATCH_LOAD EVENT(LS_DISPATCH, BIT(0))
-#define LS_DISPATCH_STORE EVENT(LS_DISPATCH, BIT(1))
-#define LS_DISPATCH_LOAD_STORE EVENT(LS_DISPATCH, BIT(2))
+#define LS_DISPATCH_LOAD RAW_EVENT(LS_DISPATCH, BIT(0))
+#define LS_DISPATCH_STORE RAW_EVENT(LS_DISPATCH, BIT(1))
+#define LS_DISPATCH_LOAD_STORE RAW_EVENT(LS_DISPATCH, BIT(2))

#define INCLUDE_MASKED_ENTRY(event_select, mask, match) \
KVM_PMU_ENCODE_MASKED_ENTRY(event_select, mask, match, false)
@@ -729,14 +677,14 @@ static void add_dummy_events(uint64_t *events, int nevents)

static void test_masked_events(struct kvm_vcpu *vcpu)
{
- int nevents = MAX_FILTER_EVENTS - MAX_TEST_EVENTS;
- uint64_t events[MAX_FILTER_EVENTS];
+ int nevents = KVM_PMU_EVENT_FILTER_MAX_EVENTS - MAX_TEST_EVENTS;
+ uint64_t events[KVM_PMU_EVENT_FILTER_MAX_EVENTS];

/* Run the test cases against a sparse PMU event filter. */
run_masked_events_tests(vcpu, events, 0);

/* Run the test cases against a dense PMU event filter. */
- add_dummy_events(events, MAX_FILTER_EVENTS);
+ add_dummy_events(events, KVM_PMU_EVENT_FILTER_MAX_EVENTS);
run_masked_events_tests(vcpu, events, nevents);
}

@@ -809,20 +757,19 @@ 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)
+static void intel_run_fixed_counter_guest_code(uint8_t idx)
{
for (;;) {
wrmsr(MSR_CORE_PERF_GLOBAL_CTRL, 0);
- wrmsr(MSR_CORE_PERF_FIXED_CTR0 + fixed_ctr_idx, 0);
+ wrmsr(MSR_CORE_PERF_FIXED_CTR0 + 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));
+ wrmsr(MSR_CORE_PERF_FIXED_CTR_CTRL, FIXED_PMC_CTRL(idx, FIXED_PMC_KERNEL));
+ wrmsr(MSR_CORE_PERF_GLOBAL_CTRL, FIXED_PMC_GLOBAL_CTRL_ENABLE(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));
+ GUEST_SYNC(rdmsr(MSR_CORE_PERF_FIXED_CTR0 + idx));
}
}

--
2.42.0.869.gea05f2083d-goog