// SPDX-License-Identifier: GPL-2.0 /* * steal/stolen time test * * Copyright (C) 2020, Red Hat, Inc. */ #define _GNU_SOURCE #include #include #include #include #include #include #include #include "test_util.h" #include "kvm_util.h" #include "processor.h" #define NR_VCPUS 4 #define ST_GPA_BASE (1 << 30) static void *st_gva[NR_VCPUS]; static uint64_t guest_stolen_time[NR_VCPUS]; #if defined(__x86_64__) /* steal_time must have 64-byte alignment */ #define STEAL_TIME_SIZE ((sizeof(struct kvm_steal_time) + 63) & ~63) static void check_status(struct kvm_steal_time *st) { GUEST_ASSERT(!(READ_ONCE(st->version) & 1)); GUEST_ASSERT(READ_ONCE(st->flags) == 0); GUEST_ASSERT(READ_ONCE(st->preempted) == 0); } static void guest_code(int cpu) { struct kvm_steal_time *st = st_gva[cpu]; uint32_t version; GUEST_ASSERT(rdmsr(MSR_KVM_STEAL_TIME) == ((uint64_t)st_gva[cpu] | KVM_MSR_ENABLED)); memset(st, 0, sizeof(*st)); GUEST_SYNC(0); check_status(st); WRITE_ONCE(guest_stolen_time[cpu], st->steal); version = READ_ONCE(st->version); check_status(st); GUEST_SYNC(1); check_status(st); GUEST_ASSERT(version < READ_ONCE(st->version)); WRITE_ONCE(guest_stolen_time[cpu], st->steal); check_status(st); GUEST_DONE(); } static void steal_time_init(struct kvm_vm *vm) { int i; if (!(kvm_get_supported_cpuid_entry(KVM_CPUID_FEATURES)->eax & KVM_FEATURE_STEAL_TIME)) { print_skip("steal-time not supported"); exit(KSFT_SKIP); } for (i = 0; i < NR_VCPUS; ++i) { int ret; /* ST_GPA_BASE is identity mapped */ st_gva[i] = (void *)(ST_GPA_BASE + i * STEAL_TIME_SIZE); sync_global_to_guest(vm, st_gva[i]); ret = _vcpu_set_msr(vm, i, MSR_KVM_STEAL_TIME, (ulong)st_gva[i] | KVM_STEAL_RESERVED_MASK); TEST_ASSERT(ret == 0, "Bad GPA didn't fail"); vcpu_set_msr(vm, i, MSR_KVM_STEAL_TIME, (ulong)st_gva[i] | KVM_MSR_ENABLED); } } static void steal_time_dump(struct kvm_vm *vm, uint32_t vcpuid) { struct kvm_steal_time *st = addr_gva2hva(vm, (ulong)st_gva[vcpuid]); int i; pr_info("VCPU%d:\n", vcpuid); pr_info(" steal: %lld\n", st->steal); pr_info(" version: %d\n", st->version); pr_info(" flags: %d\n", st->flags); pr_info(" preempted: %d\n", st->preempted); pr_info(" u8_pad: "); for (i = 0; i < 3; ++i) pr_info("%d", st->u8_pad[i]); pr_info("\n pad: "); for (i = 0; i < 11; ++i) pr_info("%d", st->pad[i]); pr_info("\n"); } #elif defined(__aarch64__) /* PV_TIME_ST must have 64-byte alignment */ #define STEAL_TIME_SIZE ((sizeof(struct st_time) + 63) & ~63) #define SMCCC_ARCH_FEATURES 0x80000001 #define PV_TIME_FEATURES 0xc5000020 #define PV_TIME_ST 0xc5000021 struct st_time { uint32_t rev; uint32_t attr; uint64_t st_time; }; static int64_t smccc(uint32_t func, uint64_t arg) { struct arm_smccc_res res; smccc_hvc(func, arg, 0, 0, 0, 0, 0, 0, &res); return res.a0; } static void check_status(struct st_time *st) { GUEST_ASSERT(READ_ONCE(st->rev) == 0); GUEST_ASSERT(READ_ONCE(st->attr) == 0); } static void guest_code(int cpu) { struct st_time *st; int64_t status; status = smccc(SMCCC_ARCH_FEATURES, PV_TIME_FEATURES); GUEST_ASSERT(status == 0); status = smccc(PV_TIME_FEATURES, PV_TIME_FEATURES); GUEST_ASSERT(status == 0); status = smccc(PV_TIME_FEATURES, PV_TIME_ST); GUEST_ASSERT(status == 0); status = smccc(PV_TIME_ST, 0); GUEST_ASSERT(status != -1); GUEST_ASSERT(status == (ulong)st_gva[cpu]); st = (struct st_time *)status; GUEST_SYNC(0); check_status(st); WRITE_ONCE(guest_stolen_time[cpu], st->st_time); GUEST_SYNC(1); check_status(st); WRITE_ONCE(guest_stolen_time[cpu], st->st_time); GUEST_DONE(); } static void steal_time_init(struct kvm_vm *vm) { struct kvm_device_attr dev = { .group = KVM_ARM_VCPU_PVTIME_CTRL, .attr = KVM_ARM_VCPU_PVTIME_IPA, }; int i, ret; ret = _vcpu_ioctl(vm, 0, KVM_HAS_DEVICE_ATTR, &dev); if (ret != 0 && errno == ENXIO) { print_skip("steal-time not supported"); exit(KSFT_SKIP); } for (i = 0; i < NR_VCPUS; ++i) { uint64_t st_ipa; vcpu_ioctl(vm, i, KVM_HAS_DEVICE_ATTR, &dev); dev.addr = (uint64_t)&st_ipa; /* ST_GPA_BASE is identity mapped */ st_gva[i] = (void *)(ST_GPA_BASE + i * STEAL_TIME_SIZE); sync_global_to_guest(vm, st_gva[i]); st_ipa = (ulong)st_gva[i] | 1; ret = _vcpu_ioctl(vm, i, KVM_SET_DEVICE_ATTR, &dev); TEST_ASSERT(ret == -1 && errno == EINVAL, "Bad IPA didn't report EINVAL"); st_ipa = (ulong)st_gva[i]; vcpu_ioctl(vm, i, KVM_SET_DEVICE_ATTR, &dev); ret = _vcpu_ioctl(vm, i, KVM_SET_DEVICE_ATTR, &dev); TEST_ASSERT(ret == -1 && errno == EEXIST, "Set IPA twice without EEXIST"); } } static void steal_time_dump(struct kvm_vm *vm, uint32_t vcpuid) { struct st_time *st = addr_gva2hva(vm, (ulong)st_gva[vcpuid]); pr_info("VCPU%d:\n", vcpuid); pr_info(" rev: %d\n", st->rev); pr_info(" attr: %d\n", st->attr); pr_info(" st_time: %ld\n", st->st_time); } #endif static void *do_steal_time(void *arg) { struct timespec ts, stop; clock_gettime(CLOCK_MONOTONIC, &ts); stop = timespec_add_ns(ts, MIN_RUN_DELAY_NS); while (1) { clock_gettime(CLOCK_MONOTONIC, &ts); if (timespec_to_ns(timespec_sub(ts, stop)) >= 0) break; } return NULL; } static void run_vcpu(struct kvm_vm *vm, uint32_t vcpuid) { struct ucall uc; vcpu_args_set(vm, vcpuid, 1, vcpuid); vcpu_ioctl(vm, vcpuid, KVM_RUN, NULL); switch (get_ucall(vm, vcpuid, &uc)) { case UCALL_SYNC: case UCALL_DONE: break; case UCALL_ABORT: TEST_ASSERT(false, "%s at %s:%ld", (const char *)uc.args[0], __FILE__, uc.args[1]); default: TEST_ASSERT(false, "Unexpected exit: %s", exit_reason_str(vcpu_state(vm, vcpuid)->exit_reason)); } } int main(int ac, char **av) { struct kvm_vm *vm; pthread_attr_t attr; pthread_t thread; cpu_set_t cpuset; unsigned int gpages; long stolen_time; long run_delay; bool verbose; int i; verbose = ac > 1 && (!strncmp(av[1], "-v", 3) || !strncmp(av[1], "--verbose", 10)); /* Set CPU affinity so we can force preemption of the VCPU */ CPU_ZERO(&cpuset); CPU_SET(0, &cpuset); pthread_attr_init(&attr); pthread_attr_setaffinity_np(&attr, sizeof(cpu_set_t), &cpuset); pthread_setaffinity_np(pthread_self(), sizeof(cpu_set_t), &cpuset); /* Create a one VCPU guest and an identity mapped memslot for the steal time structure */ vm = vm_create_default(0, 0, guest_code); gpages = vm_calc_num_guest_pages(VM_MODE_DEFAULT, STEAL_TIME_SIZE * NR_VCPUS); vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, ST_GPA_BASE, 1, gpages, 0); virt_map(vm, ST_GPA_BASE, ST_GPA_BASE, gpages); ucall_init(vm, NULL); /* Add the rest of the VCPUs */ for (i = 1; i < NR_VCPUS; ++i) vm_vcpu_add_default(vm, i, guest_code); steal_time_init(vm); /* Run test on each VCPU */ for (i = 0; i < NR_VCPUS; ++i) { /* First VCPU run initializes steal-time */ run_vcpu(vm, i); /* Second VCPU run, expect guest stolen time to be <= run_delay */ run_vcpu(vm, i); sync_global_from_guest(vm, guest_stolen_time[i]); stolen_time = guest_stolen_time[i]; run_delay = get_run_delay(); TEST_ASSERT(stolen_time <= run_delay, "Expected stolen time <= %ld, got %ld", run_delay, stolen_time); /* Steal time from the VCPU. The steal time thread has the same CPU affinity as the VCPUs. */ run_delay = get_run_delay(); pthread_create(&thread, &attr, do_steal_time, NULL); do sched_yield(); while (get_run_delay() - run_delay < MIN_RUN_DELAY_NS); pthread_join(thread, NULL); run_delay = get_run_delay() - run_delay; TEST_ASSERT(run_delay >= MIN_RUN_DELAY_NS, "Expected run_delay >= %ld, got %ld", MIN_RUN_DELAY_NS, run_delay); /* Run VCPU again to confirm stolen time is consistent with run_delay */ run_vcpu(vm, i); sync_global_from_guest(vm, guest_stolen_time[i]); stolen_time = guest_stolen_time[i] - stolen_time; TEST_ASSERT(stolen_time >= run_delay, "Expected stolen time >= %ld, got %ld", run_delay, stolen_time); if (verbose) { pr_info("VCPU%d: total-stolen-time=%ld test-stolen-time=%ld", i, guest_stolen_time[i], stolen_time); if (stolen_time == run_delay) pr_info(" (BONUS: guest test-stolen-time even exactly matches test-run_delay)"); pr_info("\n"); steal_time_dump(vm, i); } } return 0; }