Commit 4959d865 authored by Raghavendra Rao Ananta's avatar Raghavendra Rao Ananta Committed by Marc Zyngier

KVM: arm64: selftests: Add arch_timer test

Add a KVM selftest to validate the arch_timer functionality.
Primarily, the test sets up periodic timer interrupts and
validates the basic architectural expectations upon its receipt.

The test provides command-line options to configure the period
of the timer, number of iterations, and number of vCPUs.
Signed-off-by: default avatarRaghavendra Rao Ananta <rananta@google.com>
Reviewed-by: default avatarAndrew Jones <drjones@redhat.com>
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211007233439.1826892-15-rananta@google.com
parent 250b8d6c
# SPDX-License-Identifier: GPL-2.0-only
/aarch64/arch_timer
/aarch64/debug-exceptions
/aarch64/get-reg-list
/aarch64/psci_cpu_on_test
......
......@@ -86,6 +86,7 @@ TEST_GEN_PROGS_x86_64 += set_memory_region_test
TEST_GEN_PROGS_x86_64 += steal_time
TEST_GEN_PROGS_x86_64 += kvm_binary_stats_test
TEST_GEN_PROGS_aarch64 += aarch64/arch_timer
TEST_GEN_PROGS_aarch64 += aarch64/debug-exceptions
TEST_GEN_PROGS_aarch64 += aarch64/get-reg-list
TEST_GEN_PROGS_aarch64 += aarch64/psci_cpu_on_test
......
// SPDX-License-Identifier: GPL-2.0-only
/*
* arch_timer.c - Tests the aarch64 timer IRQ functionality
*
* The test validates both the virtual and physical timer IRQs using
* CVAL and TVAL registers. This consitutes the four stages in the test.
* The guest's main thread configures the timer interrupt for a stage
* and waits for it to fire, with a timeout equal to the timer period.
* It asserts that the timeout doesn't exceed the timer period.
*
* On the other hand, upon receipt of an interrupt, the guest's interrupt
* handler validates the interrupt by checking if the architectural state
* is in compliance with the specifications.
*
* The test provides command-line options to configure the timer's
* period (-p), number of vCPUs (-n), and iterations per stage (-i).
*
* Copyright (c) 2021, Google LLC.
*/
#define _GNU_SOURCE
#include <stdlib.h>
#include <pthread.h>
#include <linux/kvm.h>
#include <linux/sizes.h>
#include "kvm_util.h"
#include "processor.h"
#include "delay.h"
#include "arch_timer.h"
#include "gic.h"
#include "vgic.h"
#define NR_VCPUS_DEF 4
#define NR_TEST_ITERS_DEF 5
#define TIMER_TEST_PERIOD_MS_DEF 10
#define TIMER_TEST_ERR_MARGIN_US 100
struct test_args {
int nr_vcpus;
int nr_iter;
int timer_period_ms;
};
static struct test_args test_args = {
.nr_vcpus = NR_VCPUS_DEF,
.nr_iter = NR_TEST_ITERS_DEF,
.timer_period_ms = TIMER_TEST_PERIOD_MS_DEF,
};
#define msecs_to_usecs(msec) ((msec) * 1000LL)
#define GICD_BASE_GPA 0x8000000ULL
#define GICR_BASE_GPA 0x80A0000ULL
enum guest_stage {
GUEST_STAGE_VTIMER_CVAL = 1,
GUEST_STAGE_VTIMER_TVAL,
GUEST_STAGE_PTIMER_CVAL,
GUEST_STAGE_PTIMER_TVAL,
GUEST_STAGE_MAX,
};
/* Shared variables between host and guest */
struct test_vcpu_shared_data {
int nr_iter;
enum guest_stage guest_stage;
uint64_t xcnt;
};
struct test_vcpu {
uint32_t vcpuid;
pthread_t pt_vcpu_run;
struct kvm_vm *vm;
};
static struct test_vcpu test_vcpu[KVM_MAX_VCPUS];
static struct test_vcpu_shared_data vcpu_shared_data[KVM_MAX_VCPUS];
static int vtimer_irq, ptimer_irq;
static void
guest_configure_timer_action(struct test_vcpu_shared_data *shared_data)
{
switch (shared_data->guest_stage) {
case GUEST_STAGE_VTIMER_CVAL:
timer_set_next_cval_ms(VIRTUAL, test_args.timer_period_ms);
shared_data->xcnt = timer_get_cntct(VIRTUAL);
timer_set_ctl(VIRTUAL, CTL_ENABLE);
break;
case GUEST_STAGE_VTIMER_TVAL:
timer_set_next_tval_ms(VIRTUAL, test_args.timer_period_ms);
shared_data->xcnt = timer_get_cntct(VIRTUAL);
timer_set_ctl(VIRTUAL, CTL_ENABLE);
break;
case GUEST_STAGE_PTIMER_CVAL:
timer_set_next_cval_ms(PHYSICAL, test_args.timer_period_ms);
shared_data->xcnt = timer_get_cntct(PHYSICAL);
timer_set_ctl(PHYSICAL, CTL_ENABLE);
break;
case GUEST_STAGE_PTIMER_TVAL:
timer_set_next_tval_ms(PHYSICAL, test_args.timer_period_ms);
shared_data->xcnt = timer_get_cntct(PHYSICAL);
timer_set_ctl(PHYSICAL, CTL_ENABLE);
break;
default:
GUEST_ASSERT(0);
}
}
static void guest_validate_irq(unsigned int intid,
struct test_vcpu_shared_data *shared_data)
{
enum guest_stage stage = shared_data->guest_stage;
uint64_t xcnt = 0, xcnt_diff_us, cval = 0;
unsigned long xctl = 0;
unsigned int timer_irq = 0;
if (stage == GUEST_STAGE_VTIMER_CVAL ||
stage == GUEST_STAGE_VTIMER_TVAL) {
xctl = timer_get_ctl(VIRTUAL);
timer_set_ctl(VIRTUAL, CTL_IMASK);
xcnt = timer_get_cntct(VIRTUAL);
cval = timer_get_cval(VIRTUAL);
timer_irq = vtimer_irq;
} else if (stage == GUEST_STAGE_PTIMER_CVAL ||
stage == GUEST_STAGE_PTIMER_TVAL) {
xctl = timer_get_ctl(PHYSICAL);
timer_set_ctl(PHYSICAL, CTL_IMASK);
xcnt = timer_get_cntct(PHYSICAL);
cval = timer_get_cval(PHYSICAL);
timer_irq = ptimer_irq;
} else {
GUEST_ASSERT(0);
}
xcnt_diff_us = cycles_to_usec(xcnt - shared_data->xcnt);
/* Make sure we are dealing with the correct timer IRQ */
GUEST_ASSERT_2(intid == timer_irq, intid, timer_irq);
/* Basic 'timer condition met' check */
GUEST_ASSERT_3(xcnt >= cval, xcnt, cval, xcnt_diff_us);
GUEST_ASSERT_1(xctl & CTL_ISTATUS, xctl);
}
static void guest_irq_handler(struct ex_regs *regs)
{
unsigned int intid = gic_get_and_ack_irq();
uint32_t cpu = guest_get_vcpuid();
struct test_vcpu_shared_data *shared_data = &vcpu_shared_data[cpu];
guest_validate_irq(intid, shared_data);
WRITE_ONCE(shared_data->nr_iter, shared_data->nr_iter + 1);
gic_set_eoi(intid);
}
static void guest_run_stage(struct test_vcpu_shared_data *shared_data,
enum guest_stage stage)
{
uint32_t irq_iter, config_iter;
shared_data->guest_stage = stage;
shared_data->nr_iter = 0;
for (config_iter = 0; config_iter < test_args.nr_iter; config_iter++) {
/* Setup the next interrupt */
guest_configure_timer_action(shared_data);
/* Setup a timeout for the interrupt to arrive */
udelay(msecs_to_usecs(test_args.timer_period_ms) +
TIMER_TEST_ERR_MARGIN_US);
irq_iter = READ_ONCE(shared_data->nr_iter);
GUEST_ASSERT_2(config_iter + 1 == irq_iter,
config_iter + 1, irq_iter);
}
}
static void guest_code(void)
{
uint32_t cpu = guest_get_vcpuid();
struct test_vcpu_shared_data *shared_data = &vcpu_shared_data[cpu];
local_irq_disable();
gic_init(GIC_V3, test_args.nr_vcpus,
(void *)GICD_BASE_GPA, (void *)GICR_BASE_GPA);
timer_set_ctl(VIRTUAL, CTL_IMASK);
timer_set_ctl(PHYSICAL, CTL_IMASK);
gic_irq_enable(vtimer_irq);
gic_irq_enable(ptimer_irq);
local_irq_enable();
guest_run_stage(shared_data, GUEST_STAGE_VTIMER_CVAL);
guest_run_stage(shared_data, GUEST_STAGE_VTIMER_TVAL);
guest_run_stage(shared_data, GUEST_STAGE_PTIMER_CVAL);
guest_run_stage(shared_data, GUEST_STAGE_PTIMER_TVAL);
GUEST_DONE();
}
static void *test_vcpu_run(void *arg)
{
struct ucall uc;
struct test_vcpu *vcpu = arg;
struct kvm_vm *vm = vcpu->vm;
uint32_t vcpuid = vcpu->vcpuid;
struct test_vcpu_shared_data *shared_data = &vcpu_shared_data[vcpuid];
vcpu_run(vm, vcpuid);
switch (get_ucall(vm, vcpuid, &uc)) {
case UCALL_SYNC:
case UCALL_DONE:
break;
case UCALL_ABORT:
sync_global_from_guest(vm, *shared_data);
TEST_FAIL("%s at %s:%ld\n\tvalues: %lu, %lu; %lu, vcpu: %u; stage: %u; iter: %u",
(const char *)uc.args[0], __FILE__, uc.args[1],
uc.args[2], uc.args[3], uc.args[4], vcpuid,
shared_data->guest_stage, shared_data->nr_iter);
break;
default:
TEST_FAIL("Unexpected guest exit\n");
}
return NULL;
}
static void test_run(struct kvm_vm *vm)
{
int i, ret;
for (i = 0; i < test_args.nr_vcpus; i++) {
ret = pthread_create(&test_vcpu[i].pt_vcpu_run, NULL,
test_vcpu_run, &test_vcpu[i]);
TEST_ASSERT(!ret, "Failed to create vCPU-%d pthread\n", i);
}
for (i = 0; i < test_args.nr_vcpus; i++)
pthread_join(test_vcpu[i].pt_vcpu_run, NULL);
}
static void test_init_timer_irq(struct kvm_vm *vm)
{
/* Timer initid should be same for all the vCPUs, so query only vCPU-0 */
int vcpu0_fd = vcpu_get_fd(vm, 0);
kvm_device_access(vcpu0_fd, KVM_ARM_VCPU_TIMER_CTRL,
KVM_ARM_VCPU_TIMER_IRQ_PTIMER, &ptimer_irq, false);
kvm_device_access(vcpu0_fd, KVM_ARM_VCPU_TIMER_CTRL,
KVM_ARM_VCPU_TIMER_IRQ_VTIMER, &vtimer_irq, false);
sync_global_to_guest(vm, ptimer_irq);
sync_global_to_guest(vm, vtimer_irq);
pr_debug("ptimer_irq: %d; vtimer_irq: %d\n", ptimer_irq, vtimer_irq);
}
static struct kvm_vm *test_vm_create(void)
{
struct kvm_vm *vm;
unsigned int i;
int nr_vcpus = test_args.nr_vcpus;
vm = vm_create_default_with_vcpus(nr_vcpus, 0, 0, guest_code, NULL);
vm_init_descriptor_tables(vm);
vm_install_exception_handler(vm, VECTOR_IRQ_CURRENT, guest_irq_handler);
for (i = 0; i < nr_vcpus; i++) {
vcpu_init_descriptor_tables(vm, i);
test_vcpu[i].vcpuid = i;
test_vcpu[i].vm = vm;
}
ucall_init(vm, NULL);
test_init_timer_irq(vm);
vgic_v3_setup(vm, nr_vcpus, GICD_BASE_GPA, GICR_BASE_GPA);
/* Make all the test's cmdline args visible to the guest */
sync_global_to_guest(vm, test_args);
return vm;
}
static void test_print_help(char *name)
{
pr_info("Usage: %s [-h] [-n nr_vcpus] [-i iterations] [-p timer_period_ms]\n",
name);
pr_info("\t-n: Number of vCPUs to configure (default: %u; max: %u)\n",
NR_VCPUS_DEF, KVM_MAX_VCPUS);
pr_info("\t-i: Number of iterations per stage (default: %u)\n",
NR_TEST_ITERS_DEF);
pr_info("\t-p: Periodicity (in ms) of the guest timer (default: %u)\n",
TIMER_TEST_PERIOD_MS_DEF);
pr_info("\t-h: print this help screen\n");
}
static bool parse_args(int argc, char *argv[])
{
int opt;
while ((opt = getopt(argc, argv, "hn:i:p:")) != -1) {
switch (opt) {
case 'n':
test_args.nr_vcpus = atoi(optarg);
if (test_args.nr_vcpus <= 0) {
pr_info("Positive value needed for -n\n");
goto err;
} else if (test_args.nr_vcpus > KVM_MAX_VCPUS) {
pr_info("Max allowed vCPUs: %u\n",
KVM_MAX_VCPUS);
goto err;
}
break;
case 'i':
test_args.nr_iter = atoi(optarg);
if (test_args.nr_iter <= 0) {
pr_info("Positive value needed for -i\n");
goto err;
}
break;
case 'p':
test_args.timer_period_ms = atoi(optarg);
if (test_args.timer_period_ms <= 0) {
pr_info("Positive value needed for -p\n");
goto err;
}
break;
case 'h':
default:
goto err;
}
}
return true;
err:
test_print_help(argv[0]);
return false;
}
int main(int argc, char *argv[])
{
struct kvm_vm *vm;
/* Tell stdout not to buffer its content */
setbuf(stdout, NULL);
if (!parse_args(argc, argv))
exit(KSFT_SKIP);
vm = test_vm_create();
test_run(vm);
kvm_vm_free(vm);
return 0;
}
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