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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-08-07 13:11:27 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-08-07 13:11:27 +0000
commit34996e42f82bfd60bc2c191e5cae3c6ab233ec6c (patch)
tree62db60558cbf089714b48daeabca82bf2b20b20e /tools/testing/selftests/kvm/arch_timer.c
parentAdding debian version 6.8.12-1. (diff)
downloadlinux-34996e42f82bfd60bc2c191e5cae3c6ab233ec6c.tar.xz
linux-34996e42f82bfd60bc2c191e5cae3c6ab233ec6c.zip
Merging upstream version 6.9.7.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/testing/selftests/kvm/arch_timer.c')
-rw-r--r--tools/testing/selftests/kvm/arch_timer.c259
1 files changed, 259 insertions, 0 deletions
diff --git a/tools/testing/selftests/kvm/arch_timer.c b/tools/testing/selftests/kvm/arch_timer.c
new file mode 100644
index 0000000000..ae1f1a6d83
--- /dev/null
+++ b/tools/testing/selftests/kvm/arch_timer.c
@@ -0,0 +1,259 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * arch_timer.c - Tests the arch timer IRQ functionality
+ *
+ * The guest's main thread configures the timer interrupt 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 plus
+ * a user configurable error margin(default to 100us)
+ *
+ * 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), iterations per stage (-i) and timer
+ * interrupt arrival error margin (-e). To stress-test the timer stack
+ * even more, an option to migrate the vCPUs across pCPUs (-m), at a
+ * particular rate, is also provided.
+ *
+ * Copyright (c) 2021, Google LLC.
+ */
+
+#define _GNU_SOURCE
+
+#include <stdlib.h>
+#include <pthread.h>
+#include <linux/sizes.h>
+#include <linux/bitmap.h>
+#include <sys/sysinfo.h>
+
+#include "timer_test.h"
+
+struct test_args test_args = {
+ .nr_vcpus = NR_VCPUS_DEF,
+ .nr_iter = NR_TEST_ITERS_DEF,
+ .timer_period_ms = TIMER_TEST_PERIOD_MS_DEF,
+ .migration_freq_ms = TIMER_TEST_MIGRATION_FREQ_MS,
+ .timer_err_margin_us = TIMER_TEST_ERR_MARGIN_US,
+ .reserved = 1,
+};
+
+struct kvm_vcpu *vcpus[KVM_MAX_VCPUS];
+struct test_vcpu_shared_data vcpu_shared_data[KVM_MAX_VCPUS];
+
+static pthread_t pt_vcpu_run[KVM_MAX_VCPUS];
+static unsigned long *vcpu_done_map;
+static pthread_mutex_t vcpu_done_map_lock;
+
+static void *test_vcpu_run(void *arg)
+{
+ unsigned int vcpu_idx = (unsigned long)arg;
+ struct ucall uc;
+ struct kvm_vcpu *vcpu = vcpus[vcpu_idx];
+ struct kvm_vm *vm = vcpu->vm;
+ struct test_vcpu_shared_data *shared_data = &vcpu_shared_data[vcpu_idx];
+
+ vcpu_run(vcpu);
+
+ /* Currently, any exit from guest is an indication of completion */
+ pthread_mutex_lock(&vcpu_done_map_lock);
+ __set_bit(vcpu_idx, vcpu_done_map);
+ pthread_mutex_unlock(&vcpu_done_map_lock);
+
+ switch (get_ucall(vcpu, &uc)) {
+ case UCALL_SYNC:
+ case UCALL_DONE:
+ break;
+ case UCALL_ABORT:
+ sync_global_from_guest(vm, *shared_data);
+ fprintf(stderr, "Guest assert failed, vcpu %u; stage; %u; iter: %u\n",
+ vcpu_idx, shared_data->guest_stage, shared_data->nr_iter);
+ REPORT_GUEST_ASSERT(uc);
+ break;
+ default:
+ TEST_FAIL("Unexpected guest exit");
+ }
+
+ pr_info("PASS(vCPU-%d).\n", vcpu_idx);
+
+ return NULL;
+}
+
+static uint32_t test_get_pcpu(void)
+{
+ uint32_t pcpu;
+ unsigned int nproc_conf;
+ cpu_set_t online_cpuset;
+
+ nproc_conf = get_nprocs_conf();
+ sched_getaffinity(0, sizeof(cpu_set_t), &online_cpuset);
+
+ /* Randomly find an available pCPU to place a vCPU on */
+ do {
+ pcpu = rand() % nproc_conf;
+ } while (!CPU_ISSET(pcpu, &online_cpuset));
+
+ return pcpu;
+}
+
+static int test_migrate_vcpu(unsigned int vcpu_idx)
+{
+ int ret;
+ cpu_set_t cpuset;
+ uint32_t new_pcpu = test_get_pcpu();
+
+ CPU_ZERO(&cpuset);
+ CPU_SET(new_pcpu, &cpuset);
+
+ pr_debug("Migrating vCPU: %u to pCPU: %u\n", vcpu_idx, new_pcpu);
+
+ ret = pthread_setaffinity_np(pt_vcpu_run[vcpu_idx],
+ sizeof(cpuset), &cpuset);
+
+ /* Allow the error where the vCPU thread is already finished */
+ TEST_ASSERT(ret == 0 || ret == ESRCH,
+ "Failed to migrate the vCPU:%u to pCPU: %u; ret: %d",
+ vcpu_idx, new_pcpu, ret);
+
+ return ret;
+}
+
+static void *test_vcpu_migration(void *arg)
+{
+ unsigned int i, n_done;
+ bool vcpu_done;
+
+ do {
+ usleep(msecs_to_usecs(test_args.migration_freq_ms));
+
+ for (n_done = 0, i = 0; i < test_args.nr_vcpus; i++) {
+ pthread_mutex_lock(&vcpu_done_map_lock);
+ vcpu_done = test_bit(i, vcpu_done_map);
+ pthread_mutex_unlock(&vcpu_done_map_lock);
+
+ if (vcpu_done) {
+ n_done++;
+ continue;
+ }
+
+ test_migrate_vcpu(i);
+ }
+ } while (test_args.nr_vcpus != n_done);
+
+ return NULL;
+}
+
+static void test_run(struct kvm_vm *vm)
+{
+ pthread_t pt_vcpu_migration;
+ unsigned int i;
+ int ret;
+
+ pthread_mutex_init(&vcpu_done_map_lock, NULL);
+ vcpu_done_map = bitmap_zalloc(test_args.nr_vcpus);
+ TEST_ASSERT(vcpu_done_map, "Failed to allocate vcpu done bitmap");
+
+ for (i = 0; i < (unsigned long)test_args.nr_vcpus; i++) {
+ ret = pthread_create(&pt_vcpu_run[i], NULL, test_vcpu_run,
+ (void *)(unsigned long)i);
+ TEST_ASSERT(!ret, "Failed to create vCPU-%d pthread", i);
+ }
+
+ /* Spawn a thread to control the vCPU migrations */
+ if (test_args.migration_freq_ms) {
+ srand(time(NULL));
+
+ ret = pthread_create(&pt_vcpu_migration, NULL,
+ test_vcpu_migration, NULL);
+ TEST_ASSERT(!ret, "Failed to create the migration pthread");
+ }
+
+
+ for (i = 0; i < test_args.nr_vcpus; i++)
+ pthread_join(pt_vcpu_run[i], NULL);
+
+ if (test_args.migration_freq_ms)
+ pthread_join(pt_vcpu_migration, NULL);
+
+ bitmap_free(vcpu_done_map);
+}
+
+static void test_print_help(char *name)
+{
+ pr_info("Usage: %s [-h] [-n nr_vcpus] [-i iterations] [-p timer_period_ms]\n"
+ "\t\t [-m migration_freq_ms] [-o counter_offset]\n"
+ "\t\t [-e timer_err_margin_us]\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-m: Frequency (in ms) of vCPUs to migrate to different pCPU. 0 to turn off (default: %u)\n",
+ TIMER_TEST_MIGRATION_FREQ_MS);
+ pr_info("\t-o: Counter offset (in counter cycles, default: 0) [aarch64-only]\n");
+ pr_info("\t-e: Interrupt arrival error margin (in us) of the guest timer (default: %u)\n",
+ TIMER_TEST_ERR_MARGIN_US);
+ 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:m:o:e:")) != -1) {
+ switch (opt) {
+ case 'n':
+ test_args.nr_vcpus = atoi_positive("Number of vCPUs", optarg);
+ 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_positive("Number of iterations", optarg);
+ break;
+ case 'p':
+ test_args.timer_period_ms = atoi_positive("Periodicity", optarg);
+ break;
+ case 'm':
+ test_args.migration_freq_ms = atoi_non_negative("Frequency", optarg);
+ break;
+ case 'e':
+ test_args.timer_err_margin_us = atoi_non_negative("Error Margin", optarg);
+ break;
+ case 'o':
+ test_args.counter_offset = strtol(optarg, NULL, 0);
+ test_args.reserved = 0;
+ 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;
+
+ if (!parse_args(argc, argv))
+ exit(KSFT_SKIP);
+
+ __TEST_REQUIRE(!test_args.migration_freq_ms || get_nprocs() >= 2,
+ "At least two physical CPUs needed for vCPU migration");
+
+ vm = test_vm_create();
+ test_run(vm);
+ test_vm_cleanup(vm);
+
+ return 0;
+}