diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile index 03662666b30df1..c9cdbd24872766 100644 --- a/tools/testing/selftests/kvm/Makefile +++ b/tools/testing/selftests/kvm/Makefile @@ -66,6 +66,7 @@ TEST_GEN_PROGS_x86_64 += x86_64/state_test TEST_GEN_PROGS_x86_64 += x86_64/vmx_preemption_timer_test TEST_GEN_PROGS_x86_64 += x86_64/svm_vmcall_test TEST_GEN_PROGS_x86_64 += x86_64/svm_int_ctl_test +TEST_GEN_PROGS_x86_64 += x86_64/tsc_scaling_sync TEST_GEN_PROGS_x86_64 += x86_64/sync_regs_test TEST_GEN_PROGS_x86_64 += x86_64/userspace_io_test TEST_GEN_PROGS_x86_64 += x86_64/userspace_msr_exit_test diff --git a/tools/testing/selftests/kvm/x86_64/tsc_scaling_sync.c b/tools/testing/selftests/kvm/x86_64/tsc_scaling_sync.c new file mode 100644 index 00000000000000..f0083d8cfe98cd --- /dev/null +++ b/tools/testing/selftests/kvm/x86_64/tsc_scaling_sync.c @@ -0,0 +1,119 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * svm_vmcall_test + * + * Copyright © 2021 Amazon.com, Inc. or its affiliates. + * + * Xen shared_info / pvclock testing + */ + +#include "test_util.h" +#include "kvm_util.h" +#include "processor.h" + +#include +#include +#include +#include +#include + +#define NR_TEST_VCPUS 20 + +static struct kvm_vm *vm; +pthread_spinlock_t create_lock; + +#define TEST_TSC_KHZ 2345678UL +#define TEST_TSC_OFFSET 200000000 + +uint64_t tsc_sync; +static void guest_code(void) +{ + uint64_t start_tsc, local_tsc, tmp; + + start_tsc = rdtsc(); + do { + tmp = READ_ONCE(tsc_sync); + local_tsc = rdtsc(); + WRITE_ONCE(tsc_sync, local_tsc); + if (unlikely(local_tsc < tmp)) + GUEST_SYNC_ARGS(0, local_tsc, tmp, 0, 0); + + } while (local_tsc - start_tsc < 5000 * TEST_TSC_KHZ); + + GUEST_DONE(); +} + + +static void *run_vcpu(void *_cpu_nr) +{ + unsigned long cpu = (unsigned long)_cpu_nr; + unsigned long failures = 0; + static bool first_cpu_done; + + /* The kernel is fine, but vm_vcpu_add_default() needs locking */ + pthread_spin_lock(&create_lock); + + vm_vcpu_add_default(vm, cpu, guest_code); + + if (!first_cpu_done) { + first_cpu_done = true; + vcpu_set_msr(vm, cpu, MSR_IA32_TSC, TEST_TSC_OFFSET); + } + + pthread_spin_unlock(&create_lock); + + for (;;) { + volatile struct kvm_run *run = vcpu_state(vm, cpu); + struct ucall uc; + + vcpu_run(vm, cpu); + TEST_ASSERT(run->exit_reason == KVM_EXIT_IO, + "Got exit_reason other than KVM_EXIT_IO: %u (%s)\n", + run->exit_reason, + exit_reason_str(run->exit_reason)); + + switch (get_ucall(vm, cpu, &uc)) { + case UCALL_DONE: + goto out; + + case UCALL_SYNC: + printf("Guest %ld sync %lx %lx %ld\n", cpu, uc.args[2], uc.args[3], uc.args[2] - uc.args[3]); + failures++; + break; + + default: + TEST_FAIL("Unknown ucall %lu", uc.cmd); + } + } + out: + return (void *)failures; +} + +int main(int argc, char *argv[]) +{ + if (!kvm_check_cap(KVM_CAP_VM_TSC_CONTROL)) { + print_skip("KVM_CAP_VM_TSC_CONTROL not available"); + exit(KSFT_SKIP); + } + + vm = vm_create_default_with_vcpus(0, DEFAULT_STACK_PGS * NR_TEST_VCPUS, 0, guest_code, NULL); + vm_ioctl(vm, KVM_SET_TSC_KHZ, (void *) TEST_TSC_KHZ); + + pthread_spin_init(&create_lock, PTHREAD_PROCESS_PRIVATE); + pthread_t cpu_threads[NR_TEST_VCPUS]; + unsigned long cpu; + for (cpu = 0; cpu < NR_TEST_VCPUS; cpu++) + pthread_create(&cpu_threads[cpu], NULL, run_vcpu, (void *)cpu); + + unsigned long failures = 0; + for (cpu = 0; cpu < NR_TEST_VCPUS; cpu++) { + void *this_cpu_failures; + pthread_join(cpu_threads[cpu], &this_cpu_failures); + failures += (unsigned long)this_cpu_failures; + } + + TEST_ASSERT(!failures, "TSC sync failed"); + pthread_spin_destroy(&create_lock); + kvm_vm_free(vm); + return 0; +}