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Subject[PATCH v3 14/21] KVM: selftests: Test all fungible features in PERF_CAPABILITIES
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Verify that userspace can set all fungible features in PERF_CAPABILITIES.
Drop the now unused #define of the "full-width writes" flag.

Signed-off-by: Sean Christopherson <seanjc@google.com>
---
.../selftests/kvm/x86_64/vmx_pmu_caps_test.c | 29 +++++++++++++++----
1 file changed, 24 insertions(+), 5 deletions(-)

diff --git a/tools/testing/selftests/kvm/x86_64/vmx_pmu_caps_test.c b/tools/testing/selftests/kvm/x86_64/vmx_pmu_caps_test.c
index f7a27b5c949b..2647282ff380 100644
--- a/tools/testing/selftests/kvm/x86_64/vmx_pmu_caps_test.c
+++ b/tools/testing/selftests/kvm/x86_64/vmx_pmu_caps_test.c
@@ -14,10 +14,11 @@
#define _GNU_SOURCE /* for program_invocation_short_name */
#include <sys/ioctl.h>

+#include <linux/bitmap.h>
+
#include "kvm_util.h"
#include "vmx.h"

-#define PMU_CAP_FW_WRITES (1ULL << 13)
#define PMU_CAP_LBR_FMT 0x3f

union perf_capabilities {
@@ -36,6 +37,18 @@ union perf_capabilities {
u64 capabilities;
};

+/*
+ * The LBR format and most PEBS features are immutable, all other features are
+ * fungible (if supported by the host and KVM).
+ */
+static const union perf_capabilities immutable_caps = {
+ .lbr_format = -1,
+ .pebs_trap = 1,
+ .pebs_arch_reg = 1,
+ .pebs_format = -1,
+ .pebs_baseline = 1,
+};
+
static void guest_code(void)
{
wrmsr(MSR_IA32_PERF_CAPABILITIES, PMU_CAP_LBR_FMT);
@@ -58,15 +71,22 @@ static void test_basic_perf_capabilities(union perf_capabilities host_cap)

static void test_fungible_perf_capabilities(union perf_capabilities host_cap)
{
+ const uint64_t fungible_caps = host_cap.capabilities & ~immutable_caps.capabilities;
+
struct kvm_vcpu *vcpu;
struct kvm_vm *vm = vm_create_with_one_vcpu(&vcpu, guest_code);
+ int bit;

- /* testcase 1, set capabilities when we have PDCM bit */
- vcpu_set_msr(vcpu, MSR_IA32_PERF_CAPABILITIES, PMU_CAP_FW_WRITES);
+ for_each_set_bit(bit, &fungible_caps, 64) {
+ vcpu_set_msr(vcpu, MSR_IA32_PERF_CAPABILITIES, BIT_ULL(bit));
+ vcpu_set_msr(vcpu, MSR_IA32_PERF_CAPABILITIES,
+ host_cap.capabilities & ~BIT_ULL(bit));
+ }
+ vcpu_set_msr(vcpu, MSR_IA32_PERF_CAPABILITIES, host_cap.capabilities);

/* check whatever we write with KVM_SET_MSR is _not_ modified */
vcpu_run(vcpu);
- ASSERT_EQ(vcpu_get_msr(vcpu, MSR_IA32_PERF_CAPABILITIES), PMU_CAP_FW_WRITES);
+ ASSERT_EQ(vcpu_get_msr(vcpu, MSR_IA32_PERF_CAPABILITIES), host_cap.capabilities);

kvm_vm_free(vm);
}
@@ -102,7 +122,6 @@ int main(int argc, char *argv[])
TEST_REQUIRE(kvm_cpu_property(X86_PROPERTY_PMU_VERSION) > 0);

host_cap.capabilities = kvm_get_feature_msr(MSR_IA32_PERF_CAPABILITIES);
- host_cap.capabilities &= (PMU_CAP_FW_WRITES | PMU_CAP_LBR_FMT);

TEST_ASSERT(host_cap.full_width_write,
"Full-width writes should always be supported");
--
2.40.0.rc1.284.g88254d51c5-goog
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