Re: [PATCH v5 20/22] KVM: riscv: selftests: Add SBI PMU selftest

[Andrew Jones]

On Wed, Apr 03, 2024 at 01:04:49AM -0700, Atish Patra wrote:
..
> +static void test_pmu_basic_sanity(void)
> +{
> +	long out_val = 0;
> +	bool probe;
> +	struct sbiret ret;
> +	int num_counters = 0, i;
> +	union sbi_pmu_ctr_info ctrinfo;
> +
> +	probe = guest_sbi_probe_extension(SBI_EXT_PMU, &out_val);
> +	GUEST_ASSERT(probe && out_val == 1);
> +
> +	num_counters = get_num_counters();
> +
> +	for (i = 0; i < num_counters; i++) {
> +		ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_GET_INFO, i,
> +				0, 0, 0, 0, 0);
> +
> +		/* There can be gaps in logical counter indicies*/
> +		if (ret.error)
> +			continue;
> +		GUEST_ASSERT_NE(ret.value, 0);
> +
> +		ctrinfo.value = ret.value;
> +
> +		/**
> +		 * Accesibillity check of hardware and read capability of firmware counters.

Accessibility

> +		 * The spec doesn't mandate any initial value. No need to check any value.
> +		 */
> +		read_counter(i, ctrinfo);
> +	}
> +
> +	GUEST_DONE();
> +}
> +
> +static void run_vcpu(struct kvm_vcpu *vcpu)
> +{
> +	struct ucall uc;
> +
> +	vcpu_run(vcpu);
> +	switch (get_ucall(vcpu, &uc)) {
> +	case UCALL_ABORT:
> +		REPORT_GUEST_ASSERT(uc);
> +		break;
> +	case UCALL_DONE:
> +	case UCALL_SYNC:
> +		break;
> +	default:
> +		TEST_FAIL("Unknown ucall %lu", uc.cmd);
> +		break;
> +	}
> +}
> +
> +void test_vm_destroy(struct kvm_vm *vm)
> +{
> +	memset(ctrinfo_arr, 0, sizeof(union sbi_pmu_ctr_info) * RISCV_MAX_PMU_COUNTERS);
> +	counter_mask_available = 0;
> +	kvm_vm_free(vm);
> +}
> +
> +static void test_vm_basic_test(void *guest_code)
> +{
> +	struct kvm_vm *vm;
> +	struct kvm_vcpu *vcpu;
> +
> +	vm = vm_create_with_one_vcpu(&vcpu, guest_code);
> +	__TEST_REQUIRE(__vcpu_has_sbi_ext(vcpu, KVM_RISCV_SBI_EXT_PMU),
> +				   "SBI PMU not available, skipping test");
> +	vm_init_vector_tables(vm);
> +	/* Illegal instruction handler is required to verify read access without configuration */
> +	vm_install_exception_handler(vm, EXC_INST_ILLEGAL, guest_illegal_exception_handler);

I still don't see where the "verify" part is. The handler doesn't record
that it had to handle anything.

> +
> +	vcpu_init_vector_tables(vcpu);
> +	run_vcpu(vcpu);
> +
> +	test_vm_destroy(vm);
> +}
> +
> +static void test_vm_events_test(void *guest_code)
> +{
> +	struct kvm_vm *vm = NULL;
> +	struct kvm_vcpu *vcpu = NULL;
> +
> +	vm = vm_create_with_one_vcpu(&vcpu, guest_code);
> +	__TEST_REQUIRE(__vcpu_has_sbi_ext(vcpu, KVM_RISCV_SBI_EXT_PMU),
> +				   "SBI PMU not available, skipping test");
> +	run_vcpu(vcpu);
> +
> +	test_vm_destroy(vm);
> +}
> +
> +int main(void)
> +{
> +	test_vm_basic_test(test_pmu_basic_sanity);
> +	pr_info("SBI PMU basic test : PASS\n");
> +
> +	test_vm_events_test(test_pmu_events);
> +	pr_info("SBI PMU event verification test : PASS\n");
> +
> +	return 0;
> +}
> -- 
> 2.34.1
>

Thanks,
drew