[PATCH v2 6/7] KVM: selftests: x86: Use TAP interface in the vmx_pmu_caps test

From: Thomas Huth
Date: Thu Oct 05 2023 - 11:01:13 EST


Use the kvm_test_harness.h interface in this test to get TAP
output, so that it is easier for the user to see what the test
is doing.

Signed-off-by: Thomas Huth <thuth@xxxxxxxxxx>
---
.../selftests/kvm/x86_64/vmx_pmu_caps_test.c | 50 ++++---------------
1 file changed, 11 insertions(+), 39 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 ebbcb0a3f7438..20c9c411de9fb 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
@@ -15,6 +15,7 @@

#include <linux/bitmap.h>

+#include "kvm_test_harness.h"
#include "kvm_util.h"
#include "vmx.h"

@@ -32,7 +33,7 @@ union perf_capabilities {
u64 anythread_deprecated:1;
};
u64 capabilities;
-};
+} host_cap;

/*
* The LBR format and most PEBS features are immutable, all other features are
@@ -73,19 +74,19 @@ static void guest_code(uint64_t current_val)
GUEST_DONE();
}

+KVM_ONE_VCPU_TEST_SUITE(vmx_pmu_caps, guest_code);
+
/*
* Verify that guest WRMSRs to PERF_CAPABILITIES #GP regardless of the value
* written, that the guest always sees the userspace controlled value, and that
* PERF_CAPABILITIES is immutable after KVM_RUN.
*/
-static void test_guest_wrmsr_perf_capabilities(union perf_capabilities host_cap)
+KVM_ONE_VCPU_TEST(vmx_pmu_caps, guest_wrmsr_perf_capabilities)
{
- struct kvm_vcpu *vcpu;
- struct kvm_vm *vm = vm_create_with_one_vcpu(&vcpu, guest_code);
struct ucall uc;
int r, i;

- vm_init_descriptor_tables(vm);
+ vm_init_descriptor_tables(vcpu->vm);
vcpu_init_descriptor_tables(vcpu);

vcpu_set_msr(vcpu, MSR_IA32_PERF_CAPABILITIES, host_cap.capabilities);
@@ -117,31 +118,21 @@ static void test_guest_wrmsr_perf_capabilities(union perf_capabilities host_cap)
TEST_ASSERT(!r, "Post-KVM_RUN write '0x%llx'didn't fail",
host_cap.capabilities ^ BIT_ULL(i));
}
-
- kvm_vm_free(vm);
}

/*
* Verify KVM allows writing PERF_CAPABILITIES with all KVM-supported features
* enabled, as well as '0' (to disable all features).
*/
-static void test_basic_perf_capabilities(union perf_capabilities host_cap)
+KVM_ONE_VCPU_TEST(vmx_pmu_caps, basic_perf_capabilities)
{
- struct kvm_vcpu *vcpu;
- struct kvm_vm *vm = vm_create_with_one_vcpu(&vcpu, NULL);
-
vcpu_set_msr(vcpu, MSR_IA32_PERF_CAPABILITIES, 0);
vcpu_set_msr(vcpu, MSR_IA32_PERF_CAPABILITIES, host_cap.capabilities);
-
- kvm_vm_free(vm);
}

-static void test_fungible_perf_capabilities(union perf_capabilities host_cap)
+KVM_ONE_VCPU_TEST(vmx_pmu_caps, fungible_perf_capabilities)
{
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, NULL);
int bit;

for_each_set_bit(bit, &fungible_caps, 64) {
@@ -150,8 +141,6 @@ static void test_fungible_perf_capabilities(union perf_capabilities host_cap)
host_cap.capabilities & ~BIT_ULL(bit));
}
vcpu_set_msr(vcpu, MSR_IA32_PERF_CAPABILITIES, host_cap.capabilities);
-
- kvm_vm_free(vm);
}

/*
@@ -160,14 +149,11 @@ static void test_fungible_perf_capabilities(union perf_capabilities host_cap)
* separately as they are multi-bit values, e.g. toggling or setting a single
* bit can generate a false positive without dedicated safeguards.
*/
-static void test_immutable_perf_capabilities(union perf_capabilities host_cap)
+KVM_ONE_VCPU_TEST(vmx_pmu_caps, immutable_perf_capabilities)
{
const uint64_t reserved_caps = (~host_cap.capabilities |
immutable_caps.capabilities) &
~format_caps.capabilities;
-
- struct kvm_vcpu *vcpu;
- struct kvm_vm *vm = vm_create_with_one_vcpu(&vcpu, NULL);
union perf_capabilities val = host_cap;
int r, bit;

@@ -201,8 +187,6 @@ static void test_immutable_perf_capabilities(union perf_capabilities host_cap)
TEST_ASSERT(!r, "Bad PEBS FMT = 0x%x didn't fail, host = 0x%x",
val.pebs_format, host_cap.pebs_format);
}
-
- kvm_vm_free(vm);
}

/*
@@ -211,17 +195,13 @@ static void test_immutable_perf_capabilities(union perf_capabilities host_cap)
* LBR_TOS as those bits are writable across all uarch implementations (arch
* LBRs will need to poke a different MSR).
*/
-static void test_lbr_perf_capabilities(union perf_capabilities host_cap)
+KVM_ONE_VCPU_TEST(vmx_pmu_caps, lbr_perf_capabilities)
{
- struct kvm_vcpu *vcpu;
- struct kvm_vm *vm;
int r;

if (!host_cap.lbr_format)
return;

- vm = vm_create_with_one_vcpu(&vcpu, NULL);
-
vcpu_set_msr(vcpu, MSR_IA32_PERF_CAPABILITIES, host_cap.capabilities);
vcpu_set_msr(vcpu, MSR_LBR_TOS, 7);

@@ -229,14 +209,10 @@ static void test_lbr_perf_capabilities(union perf_capabilities host_cap)

r = _vcpu_set_msr(vcpu, MSR_LBR_TOS, 7);
TEST_ASSERT(!r, "Writing LBR_TOS should fail after disabling vPMU");
-
- kvm_vm_free(vm);
}

int main(int argc, char *argv[])
{
- union perf_capabilities host_cap;
-
TEST_REQUIRE(get_kvm_param_bool("enable_pmu"));
TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_PDCM));

@@ -248,9 +224,5 @@ int main(int argc, char *argv[])
TEST_ASSERT(host_cap.full_width_write,
"Full-width writes should always be supported");

- test_basic_perf_capabilities(host_cap);
- test_fungible_perf_capabilities(host_cap);
- test_immutable_perf_capabilities(host_cap);
- test_guest_wrmsr_perf_capabilities(host_cap);
- test_lbr_perf_capabilities(host_cap);
+ return test_harness_run(argc, argv);
}
--
2.41.0