[REPOST PATCH 05/16] selftests: KVM: aarch64: Refactor the vPMU counter access tests

From: Raghavendra Rao Ananta
Date: Tue Feb 14 2023 - 20:07:45 EST


Refactor the existing counter access tests into its own
independent functions and make running the tests generic
to make way for the upcoming tests.

As a part of the refactoring, rename the test file to a more
genetric name vpmu_test.c.

No functional change intended.

Signed-off-by: Raghavendra Rao Ananta <rananta@xxxxxxxxxx>
---
tools/testing/selftests/kvm/Makefile | 2 +-
.../{vpmu_counter_access.c => vpmu_test.c} | 142 ++++++++++++------
2 files changed, 100 insertions(+), 44 deletions(-)
rename tools/testing/selftests/kvm/aarch64/{vpmu_counter_access.c => vpmu_test.c} (88%)

diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index b27fea0ce5918..a4d262e139b18 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -143,7 +143,7 @@ TEST_GEN_PROGS_aarch64 += aarch64/psci_test
TEST_GEN_PROGS_aarch64 += aarch64/vcpu_width_config
TEST_GEN_PROGS_aarch64 += aarch64/vgic_init
TEST_GEN_PROGS_aarch64 += aarch64/vgic_irq
-TEST_GEN_PROGS_aarch64 += aarch64/vpmu_counter_access
+TEST_GEN_PROGS_aarch64 += aarch64/vpmu_test
TEST_GEN_PROGS_aarch64 += access_tracking_perf_test
TEST_GEN_PROGS_aarch64 += demand_paging_test
TEST_GEN_PROGS_aarch64 += dirty_log_test
diff --git a/tools/testing/selftests/kvm/aarch64/vpmu_counter_access.c b/tools/testing/selftests/kvm/aarch64/vpmu_test.c
similarity index 88%
rename from tools/testing/selftests/kvm/aarch64/vpmu_counter_access.c
rename to tools/testing/selftests/kvm/aarch64/vpmu_test.c
index 453f0dd240f44..d72c3c9b9c39f 100644
--- a/tools/testing/selftests/kvm/aarch64/vpmu_counter_access.c
+++ b/tools/testing/selftests/kvm/aarch64/vpmu_test.c
@@ -1,6 +1,6 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
- * vpmu_counter_access - Test vPMU event counter access
+ * vpmu_test - Test the vPMU
*
* Copyright (c) 2022 Google LLC.
*
@@ -147,6 +147,11 @@ static inline void disable_counter(int idx)
isb();
}

+static inline uint64_t get_pmcr_n(void)
+{
+ return FIELD_GET(ARMV8_PMU_PMCR_N, read_sysreg(pmcr_el0));
+}
+
/*
* The pmc_accessor structure has pointers to PMEV{CNTR,TYPER}<n>_EL0
* accessors that test cases will use. Each of the accessors will
@@ -183,6 +188,23 @@ struct pmc_accessor pmc_accessors[] = {
uint64_t expected_ec = INVALID_EC;
uint64_t op_end_addr;

+struct vpmu_vm {
+ struct kvm_vm *vm;
+ struct kvm_vcpu *vcpu;
+ int gic_fd;
+};
+
+enum test_stage {
+ TEST_STAGE_COUNTER_ACCESS = 1,
+};
+
+struct guest_data {
+ enum test_stage test_stage;
+ uint64_t expected_pmcr_n;
+};
+
+static struct guest_data guest_data;
+
static void guest_sync_handler(struct ex_regs *regs)
{
uint64_t esr, ec;
@@ -295,7 +317,7 @@ static void test_bitmap_pmu_regs(int pmc_idx, bool set_op)
write_sysreg(test_bit, pmovsset_el0);

/* The bit will be set only if the counter is implemented */
- pmcr_n = FIELD_GET(ARMV8_PMU_PMCR_N, read_sysreg(pmcr_el0));
+ pmcr_n = get_pmcr_n();
set_expected = (pmc_idx < pmcr_n) ? true : false;
} else {
write_sysreg(test_bit, pmcntenclr_el0);
@@ -424,15 +446,14 @@ static void test_access_invalid_pmc_regs(struct pmc_accessor *acc, int pmc_idx)
* if reading/writing PMU registers for implemented or unimplemented
* counters can work as expected.
*/
-static void guest_code(uint64_t expected_pmcr_n)
+static void guest_counter_access_test(uint64_t expected_pmcr_n)
{
- uint64_t pmcr, pmcr_n, unimp_mask;
+ uint64_t pmcr_n, unimp_mask;
int i, pmc;

GUEST_ASSERT(expected_pmcr_n <= ARMV8_PMU_MAX_GENERAL_COUNTERS);

- pmcr = read_sysreg(pmcr_el0);
- pmcr_n = FIELD_GET(ARMV8_PMU_PMCR_N, pmcr);
+ pmcr_n = get_pmcr_n();

/* Make sure that PMCR_EL0.N indicates the value userspace set */
GUEST_ASSERT_2(pmcr_n == expected_pmcr_n, pmcr_n, expected_pmcr_n);
@@ -462,6 +483,18 @@ static void guest_code(uint64_t expected_pmcr_n)
for (pmc = pmcr_n; pmc < ARMV8_PMU_MAX_GENERAL_COUNTERS; pmc++)
test_access_invalid_pmc_regs(&pmc_accessors[i], pmc);
}
+}
+
+static void guest_code(void)
+{
+ switch (guest_data.test_stage) {
+ case TEST_STAGE_COUNTER_ACCESS:
+ guest_counter_access_test(guest_data.expected_pmcr_n);
+ break;
+ default:
+ GUEST_ASSERT_1(0, guest_data.test_stage);
+ }
+
GUEST_DONE();
}

@@ -469,14 +502,14 @@ static void guest_code(uint64_t expected_pmcr_n)
#define GICR_BASE_GPA 0x80A0000ULL

/* Create a VM that has one vCPU with PMUv3 configured. */
-static struct kvm_vm *create_vpmu_vm(void *guest_code, struct kvm_vcpu **vcpup,
- int *gic_fd)
+static struct vpmu_vm *create_vpmu_vm(void *guest_code)
{
struct kvm_vm *vm;
struct kvm_vcpu *vcpu;
struct kvm_vcpu_init init;
uint8_t pmuver, ec;
uint64_t dfr0, irq = 23;
+ struct vpmu_vm *vpmu_vm;
struct kvm_device_attr irq_attr = {
.group = KVM_ARM_VCPU_PMU_V3_CTRL,
.attr = KVM_ARM_VCPU_PMU_V3_IRQ,
@@ -487,7 +520,10 @@ static struct kvm_vm *create_vpmu_vm(void *guest_code, struct kvm_vcpu **vcpup,
.attr = KVM_ARM_VCPU_PMU_V3_INIT,
};

- vm = vm_create(1);
+ vpmu_vm = calloc(1, sizeof(*vpmu_vm));
+ TEST_ASSERT(vpmu_vm, "Failed to allocate vpmu_vm");
+
+ vpmu_vm->vm = vm = vm_create(1);
vm_init_descriptor_tables(vm);
/* Catch exceptions for easier debugging */
for (ec = 0; ec < ESR_EC_NUM; ec++) {
@@ -498,9 +534,9 @@ static struct kvm_vm *create_vpmu_vm(void *guest_code, struct kvm_vcpu **vcpup,
/* Create vCPU with PMUv3 */
vm_ioctl(vm, KVM_ARM_PREFERRED_TARGET, &init);
init.features[0] |= (1 << KVM_ARM_VCPU_PMU_V3);
- vcpu = aarch64_vcpu_add(vm, 0, &init, guest_code);
+ vpmu_vm->vcpu = vcpu = aarch64_vcpu_add(vm, 0, &init, guest_code);
vcpu_init_descriptor_tables(vcpu);
- *gic_fd = vgic_v3_setup(vm, 1, 64, GICD_BASE_GPA, GICR_BASE_GPA);
+ vpmu_vm->gic_fd = vgic_v3_setup(vm, 1, 64, GICD_BASE_GPA, GICR_BASE_GPA);

/* Make sure that PMUv3 support is indicated in the ID register */
vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64DFR0_EL1), &dfr0);
@@ -513,15 +549,21 @@ static struct kvm_vm *create_vpmu_vm(void *guest_code, struct kvm_vcpu **vcpup,
vcpu_ioctl(vcpu, KVM_SET_DEVICE_ATTR, &irq_attr);
vcpu_ioctl(vcpu, KVM_SET_DEVICE_ATTR, &init_attr);

- *vcpup = vcpu;
- return vm;
+ return vpmu_vm;
+}
+
+static void destroy_vpmu_vm(struct vpmu_vm *vpmu_vm)
+{
+ close(vpmu_vm->gic_fd);
+ kvm_vm_free(vpmu_vm->vm);
+ free(vpmu_vm);
}

-static void run_vcpu(struct kvm_vcpu *vcpu, uint64_t pmcr_n)
+static void run_vcpu(struct kvm_vcpu *vcpu)
{
struct ucall uc;

- vcpu_args_set(vcpu, 1, pmcr_n);
+ sync_global_to_guest(vcpu->vm, guest_data);
vcpu_run(vcpu);
switch (get_ucall(vcpu, &uc)) {
case UCALL_ABORT:
@@ -539,16 +581,18 @@ static void run_vcpu(struct kvm_vcpu *vcpu, uint64_t pmcr_n)
* Create a guest with one vCPU, set the PMCR_EL0.N for the vCPU to @pmcr_n,
* and run the test.
*/
-static void run_test(uint64_t pmcr_n)
+static void run_counter_access_test(uint64_t pmcr_n)
{
- struct kvm_vm *vm;
+ struct vpmu_vm *vpmu_vm;
struct kvm_vcpu *vcpu;
- int gic_fd;
uint64_t sp, pmcr, pmcr_orig;
struct kvm_vcpu_init init;

+ guest_data.expected_pmcr_n = pmcr_n;
+
pr_debug("Test with pmcr_n %lu\n", pmcr_n);
- vm = create_vpmu_vm(guest_code, &vcpu, &gic_fd);
+ vpmu_vm = create_vpmu_vm(guest_code);
+ vcpu = vpmu_vm->vcpu;

/* Save the initial sp to restore them later to run the guest again */
vcpu_get_reg(vcpu, ARM64_CORE_REG(sp_el1), &sp);
@@ -559,23 +603,22 @@ static void run_test(uint64_t pmcr_n)
pmcr |= (pmcr_n << ARMV8_PMU_PMCR_N_SHIFT);
vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_PMCR_EL0), pmcr);

- run_vcpu(vcpu, pmcr_n);
+ run_vcpu(vcpu);

/*
* Reset and re-initialize the vCPU, and run the guest code again to
* check if PMCR_EL0.N is preserved.
*/
- vm_ioctl(vm, KVM_ARM_PREFERRED_TARGET, &init);
+ vm_ioctl(vpmu_vm->vm, KVM_ARM_PREFERRED_TARGET, &init);
init.features[0] |= (1 << KVM_ARM_VCPU_PMU_V3);
aarch64_vcpu_setup(vcpu, &init);
vcpu_init_descriptor_tables(vcpu);
vcpu_set_reg(vcpu, ARM64_CORE_REG(sp_el1), sp);
vcpu_set_reg(vcpu, ARM64_CORE_REG(regs.pc), (uint64_t)guest_code);

- run_vcpu(vcpu, pmcr_n);
+ run_vcpu(vcpu);

- close(gic_fd);
- kvm_vm_free(vm);
+ destroy_vpmu_vm(vpmu_vm);
}

/*
@@ -583,15 +626,18 @@ static void run_test(uint64_t pmcr_n)
* the vCPU to @pmcr_n, which is larger than the host value.
* The attempt should fail as @pmcr_n is too big to set for the vCPU.
*/
-static void run_error_test(uint64_t pmcr_n)
+static void run_counter_access_error_test(uint64_t pmcr_n)
{
- struct kvm_vm *vm;
+ struct vpmu_vm *vpmu_vm;
struct kvm_vcpu *vcpu;
- int gic_fd, ret;
+ int ret;
uint64_t pmcr, pmcr_orig;

+ guest_data.expected_pmcr_n = pmcr_n;
+
pr_debug("Error test with pmcr_n %lu (larger than the host)\n", pmcr_n);
- vm = create_vpmu_vm(guest_code, &vcpu, &gic_fd);
+ vpmu_vm = create_vpmu_vm(guest_code);
+ vcpu = vpmu_vm->vcpu;

/* Update the PMCR_EL0.N with @pmcr_n */
vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(SYS_PMCR_EL0), &pmcr_orig);
@@ -603,8 +649,25 @@ static void run_error_test(uint64_t pmcr_n)
TEST_ASSERT(ret, "Setting PMCR to 0x%lx (orig PMCR 0x%lx) didn't fail",
pmcr, pmcr_orig);

- close(gic_fd);
- kvm_vm_free(vm);
+ destroy_vpmu_vm(vpmu_vm);
+}
+
+static void run_counter_access_tests(uint64_t pmcr_n)
+{
+ uint64_t i;
+
+ guest_data.test_stage = TEST_STAGE_COUNTER_ACCESS;
+
+ for (i = 0; i <= pmcr_n; i++)
+ run_counter_access_test(i);
+
+ for (i = pmcr_n + 1; i < ARMV8_PMU_MAX_COUNTERS; i++)
+ run_counter_access_error_test(i);
+}
+
+static void run_tests(uint64_t pmcr_n)
+{
+ run_counter_access_tests(pmcr_n);
}

/*
@@ -613,30 +676,23 @@ static void run_error_test(uint64_t pmcr_n)
*/
static uint64_t get_pmcr_n_limit(void)
{
- struct kvm_vm *vm;
- struct kvm_vcpu *vcpu;
- int gic_fd;
+ struct vpmu_vm *vpmu_vm;
uint64_t pmcr;

- vm = create_vpmu_vm(guest_code, &vcpu, &gic_fd);
- vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(SYS_PMCR_EL0), &pmcr);
- close(gic_fd);
- kvm_vm_free(vm);
+ vpmu_vm = create_vpmu_vm(guest_code);
+ vcpu_get_reg(vpmu_vm->vcpu, KVM_ARM64_SYS_REG(SYS_PMCR_EL0), &pmcr);
+ destroy_vpmu_vm(vpmu_vm);
return FIELD_GET(ARMV8_PMU_PMCR_N, pmcr);
}

int main(void)
{
- uint64_t i, pmcr_n;
+ uint64_t pmcr_n;

TEST_REQUIRE(kvm_has_cap(KVM_CAP_ARM_PMU_V3));

pmcr_n = get_pmcr_n_limit();
- for (i = 0; i <= pmcr_n; i++)
- run_test(i);
-
- for (i = pmcr_n + 1; i < ARMV8_PMU_MAX_COUNTERS; i++)
- run_error_test(i);
+ run_tests(pmcr_n);

return 0;
}
--
2.39.1.581.gbfd45094c4-goog