1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright © 2021 Amazon.com, Inc. or its affiliates. 4 */ 5 6 #include "test_util.h" 7 #include "kvm_util.h" 8 #include "processor.h" 9 10 #include <stdint.h> 11 #include <time.h> 12 #include <sched.h> 13 #include <signal.h> 14 #include <pthread.h> 15 16 #define NR_TEST_VCPUS 20 17 18 static struct kvm_vm *vm; 19 pthread_spinlock_t create_lock; 20 21 #define TEST_TSC_KHZ 2345678UL 22 #define TEST_TSC_OFFSET 200000000 23 24 uint64_t tsc_sync; 25 static void guest_code(void) 26 { 27 uint64_t start_tsc, local_tsc, tmp; 28 29 start_tsc = rdtsc(); 30 do { 31 tmp = READ_ONCE(tsc_sync); 32 local_tsc = rdtsc(); 33 WRITE_ONCE(tsc_sync, local_tsc); 34 if (unlikely(local_tsc < tmp)) 35 GUEST_SYNC_ARGS(0, local_tsc, tmp, 0, 0); 36 37 } while (local_tsc - start_tsc < 5000 * TEST_TSC_KHZ); 38 39 GUEST_DONE(); 40 } 41 42 43 static void *run_vcpu(void *_cpu_nr) 44 { 45 unsigned long vcpu_id = (unsigned long)_cpu_nr; 46 unsigned long failures = 0; 47 static bool first_cpu_done; 48 struct kvm_vcpu *vcpu; 49 50 /* The kernel is fine, but vm_vcpu_add() needs locking */ 51 pthread_spin_lock(&create_lock); 52 53 vcpu = vm_vcpu_add(vm, vcpu_id, guest_code); 54 55 if (!first_cpu_done) { 56 first_cpu_done = true; 57 vcpu_set_msr(vcpu, MSR_IA32_TSC, TEST_TSC_OFFSET); 58 } 59 60 pthread_spin_unlock(&create_lock); 61 62 for (;;) { 63 struct ucall uc; 64 65 vcpu_run(vcpu); 66 TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_IO); 67 68 switch (get_ucall(vcpu, &uc)) { 69 case UCALL_DONE: 70 goto out; 71 72 case UCALL_SYNC: 73 printf("Guest %d sync %lx %lx %ld\n", vcpu->id, 74 uc.args[2], uc.args[3], uc.args[2] - uc.args[3]); 75 failures++; 76 break; 77 78 default: 79 TEST_FAIL("Unknown ucall %lu", uc.cmd); 80 } 81 } 82 out: 83 return (void *)failures; 84 } 85 86 int main(int argc, char *argv[]) 87 { 88 TEST_REQUIRE(kvm_has_cap(KVM_CAP_VM_TSC_CONTROL)); 89 90 vm = vm_create(NR_TEST_VCPUS); 91 vm_ioctl(vm, KVM_SET_TSC_KHZ, (void *) TEST_TSC_KHZ); 92 93 pthread_spin_init(&create_lock, PTHREAD_PROCESS_PRIVATE); 94 pthread_t cpu_threads[NR_TEST_VCPUS]; 95 unsigned long cpu; 96 for (cpu = 0; cpu < NR_TEST_VCPUS; cpu++) 97 pthread_create(&cpu_threads[cpu], NULL, run_vcpu, (void *)cpu); 98 99 unsigned long failures = 0; 100 for (cpu = 0; cpu < NR_TEST_VCPUS; cpu++) { 101 void *this_cpu_failures; 102 pthread_join(cpu_threads[cpu], &this_cpu_failures); 103 failures += (unsigned long)this_cpu_failures; 104 } 105 106 TEST_ASSERT(!failures, "TSC sync failed"); 107 pthread_spin_destroy(&create_lock); 108 kvm_vm_free(vm); 109 return 0; 110 } 111