diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /tools/testing/selftests/kvm/steal_time.c | |
parent | Initial commit. (diff) | |
download | linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip |
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/testing/selftests/kvm/steal_time.c')
-rw-r--r-- | tools/testing/selftests/kvm/steal_time.c | 321 |
1 files changed, 321 insertions, 0 deletions
diff --git a/tools/testing/selftests/kvm/steal_time.c b/tools/testing/selftests/kvm/steal_time.c new file mode 100644 index 0000000000..171adfb2a6 --- /dev/null +++ b/tools/testing/selftests/kvm/steal_time.c @@ -0,0 +1,321 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * steal/stolen time test + * + * Copyright (C) 2020, Red Hat, Inc. + */ +#define _GNU_SOURCE +#include <stdio.h> +#include <time.h> +#include <sched.h> +#include <pthread.h> +#include <linux/kernel.h> +#include <asm/kvm.h> +#include <asm/kvm_para.h> + +#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_EQ(READ_ONCE(st->flags), 0); + GUEST_ASSERT_EQ(READ_ONCE(st->preempted), 0); +} + +static void guest_code(int cpu) +{ + struct kvm_steal_time *st = st_gva[cpu]; + uint32_t version; + + GUEST_ASSERT_EQ(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 bool is_steal_time_supported(struct kvm_vcpu *vcpu) +{ + return kvm_cpu_has(X86_FEATURE_KVM_STEAL_TIME); +} + +static void steal_time_init(struct kvm_vcpu *vcpu, uint32_t i) +{ + int ret; + + /* ST_GPA_BASE is identity mapped */ + st_gva[i] = (void *)(ST_GPA_BASE + i * STEAL_TIME_SIZE); + sync_global_to_guest(vcpu->vm, st_gva[i]); + + ret = _vcpu_set_msr(vcpu, MSR_KVM_STEAL_TIME, + (ulong)st_gva[i] | KVM_STEAL_RESERVED_MASK); + TEST_ASSERT(ret == 0, "Bad GPA didn't fail"); + + vcpu_set_msr(vcpu, MSR_KVM_STEAL_TIME, (ulong)st_gva[i] | KVM_MSR_ENABLED); +} + +static void steal_time_dump(struct kvm_vm *vm, uint32_t vcpu_idx) +{ + struct kvm_steal_time *st = addr_gva2hva(vm, (ulong)st_gva[vcpu_idx]); + int i; + + pr_info("VCPU%d:\n", vcpu_idx); + 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_EQ(READ_ONCE(st->rev), 0); + GUEST_ASSERT_EQ(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_EQ(status, 0); + status = smccc(PV_TIME_FEATURES, PV_TIME_FEATURES); + GUEST_ASSERT_EQ(status, 0); + status = smccc(PV_TIME_FEATURES, PV_TIME_ST); + GUEST_ASSERT_EQ(status, 0); + + status = smccc(PV_TIME_ST, 0); + GUEST_ASSERT_NE(status, -1); + GUEST_ASSERT_EQ(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 bool is_steal_time_supported(struct kvm_vcpu *vcpu) +{ + struct kvm_device_attr dev = { + .group = KVM_ARM_VCPU_PVTIME_CTRL, + .attr = KVM_ARM_VCPU_PVTIME_IPA, + }; + + return !__vcpu_ioctl(vcpu, KVM_HAS_DEVICE_ATTR, &dev); +} + +static void steal_time_init(struct kvm_vcpu *vcpu, uint32_t i) +{ + struct kvm_vm *vm = vcpu->vm; + uint64_t st_ipa; + int ret; + + struct kvm_device_attr dev = { + .group = KVM_ARM_VCPU_PVTIME_CTRL, + .attr = KVM_ARM_VCPU_PVTIME_IPA, + .addr = (uint64_t)&st_ipa, + }; + + vcpu_ioctl(vcpu, KVM_HAS_DEVICE_ATTR, &dev); + + /* 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(vcpu, 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(vcpu, KVM_SET_DEVICE_ATTR, &dev); + + ret = __vcpu_ioctl(vcpu, 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 vcpu_idx) +{ + struct st_time *st = addr_gva2hva(vm, (ulong)st_gva[vcpu_idx]); + + pr_info("VCPU%d:\n", vcpu_idx); + 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_vcpu *vcpu) +{ + struct ucall uc; + + vcpu_run(vcpu); + + switch (get_ucall(vcpu, &uc)) { + case UCALL_SYNC: + case UCALL_DONE: + break; + case UCALL_ABORT: + REPORT_GUEST_ASSERT(uc); + default: + TEST_ASSERT(false, "Unexpected exit: %s", + exit_reason_str(vcpu->run->exit_reason)); + } +} + +int main(int ac, char **av) +{ + struct kvm_vcpu *vcpus[NR_VCPUS]; + 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 VM and an identity mapped memslot for the steal time structure */ + vm = vm_create_with_vcpus(NR_VCPUS, guest_code, vcpus); + 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); + + TEST_REQUIRE(is_steal_time_supported(vcpus[0])); + + /* Run test on each VCPU */ + for (i = 0; i < NR_VCPUS; ++i) { + steal_time_init(vcpus[i], i); + + vcpu_args_set(vcpus[i], 1, i); + + /* First VCPU run initializes steal-time */ + run_vcpu(vcpus[i]); + + /* Second VCPU run, expect guest stolen time to be <= run_delay */ + run_vcpu(vcpus[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(vcpus[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; +} |