Merge branch kvm-arm64/selftest/access-tracking into kvmarm-master/next

* kvm-arm64/selftest/access-tracking:
  : .
  : Small series to add support for arm64 to access_tracking_perf_test and
  : correct a couple bugs along the way.
  :
  : Patches courtesy of Oliver Upton.
  : .
  KVM: selftests: Build access_tracking_perf_test for arm64
  KVM: selftests: Have perf_test_util signal when to stop vCPUs
Signed-off-by: Marc Zyngier <maz@kernel.org>

tools/testing/selftests/kvm/Makefile

@@ -158,6 +158,7 @@ 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 += access_tracking_perf_test
 TEST_GEN_PROGS_aarch64 += demand_paging_test
 TEST_GEN_PROGS_aarch64 += dirty_log_test
 TEST_GEN_PROGS_aarch64 += dirty_log_perf_test

tools/testing/selftests/kvm/access_tracking_perf_test.c

@@ -58,9 +58,6 @@ static enum {
 	ITERATION_MARK_IDLE,
 } iteration_work;
 
-/* Set to true when vCPU threads should exit. */
-static bool done;
-
 /* The iteration that was last completed by each vCPU. */
 static int vcpu_last_completed_iteration[KVM_MAX_VCPUS];
 
@@ -211,7 +208,7 @@ static bool spin_wait_for_next_iteration(int *current_iteration)
 	int last_iteration = *current_iteration;
 
 	do {
-		if (READ_ONCE(done))
+		if (READ_ONCE(perf_test_args.stop_vcpus))
 			return false;
 
 		*current_iteration = READ_ONCE(iteration);
@@ -321,9 +318,6 @@ static void run_test(enum vm_guest_mode mode, void *arg)
 	mark_memory_idle(vm, nr_vcpus);
 	access_memory(vm, nr_vcpus, ACCESS_READ, "Reading from idle memory");
 
-	/* Set done to signal the vCPU threads to exit */
-	done = true;
-
 	perf_test_join_vcpu_threads(nr_vcpus);
 	perf_test_destroy_vm(vm);
 }

tools/testing/selftests/kvm/include/perf_test_util.h

@@ -40,6 +40,9 @@ struct perf_test_args {
 	/* Run vCPUs in L2 instead of L1, if the architecture supports it. */
 	bool nested;
 
+	/* Test is done, stop running vCPUs. */
+	bool stop_vcpus;
+
 	struct perf_test_vcpu_args vcpu_args[KVM_MAX_VCPUS];
 };
 

tools/testing/selftests/kvm/lib/perf_test_util.c

@@ -267,6 +267,7 @@ void perf_test_start_vcpu_threads(int nr_vcpus,
 
 	vcpu_thread_fn = vcpu_fn;
 	WRITE_ONCE(all_vcpu_threads_running, false);
+	WRITE_ONCE(perf_test_args.stop_vcpus, false);
 
 	for (i = 0; i < nr_vcpus; i++) {
 		struct vcpu_thread *vcpu = &vcpu_threads[i];
@@ -289,6 +290,8 @@ void perf_test_join_vcpu_threads(int nr_vcpus)
 {
 	int i;
 
+	WRITE_ONCE(perf_test_args.stop_vcpus, true);
+
 	for (i = 0; i < nr_vcpus; i++)
 		pthread_join(vcpu_threads[i].thread, NULL);
 }

tools/testing/selftests/kvm/memslot_modification_stress_test.c

@@ -34,8 +34,6 @@
 static int nr_vcpus = 1;
 static uint64_t guest_percpu_mem_size = DEFAULT_PER_VCPU_MEM_SIZE;
 
-static bool run_vcpus = true;
-
 static void vcpu_worker(struct perf_test_vcpu_args *vcpu_args)
 {
 	struct kvm_vcpu *vcpu = vcpu_args->vcpu;
@@ -45,7 +43,7 @@ static void vcpu_worker(struct perf_test_vcpu_args *vcpu_args)
 	run = vcpu->run;
 
 	/* Let the guest access its memory until a stop signal is received */
-	while (READ_ONCE(run_vcpus)) {
+	while (!READ_ONCE(perf_test_args.stop_vcpus)) {
 		ret = _vcpu_run(vcpu);
 		TEST_ASSERT(ret == 0, "vcpu_run failed: %d\n", ret);
 
@@ -110,8 +108,6 @@ static void run_test(enum vm_guest_mode mode, void *arg)
 	add_remove_memslot(vm, p->memslot_modification_delay,
 			   p->nr_memslot_modifications);
 
-	run_vcpus = false;
-
 	perf_test_join_vcpu_threads(nr_vcpus);
 	pr_info("All vCPU threads joined\n");