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// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright © 2021 Amazon.com, Inc. or its affiliates.
*/
#include "test_util.h"
#include "kvm_util.h"
#include "processor.h"
#include <stdint.h>
#include <time.h>
#include <sched.h>
#include <signal.h>
#include <pthread.h>
#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 vcpu_id = (unsigned long)_cpu_nr;
unsigned long failures = 0;
static bool first_cpu_done;
struct kvm_vcpu *vcpu;
/* The kernel is fine, but vm_vcpu_add() needs locking */
pthread_spin_lock(&create_lock);
vcpu = vm_vcpu_add(vm, vcpu_id, guest_code);
if (!first_cpu_done) {
first_cpu_done = true;
vcpu_set_msr(vcpu, MSR_IA32_TSC, TEST_TSC_OFFSET);
}
pthread_spin_unlock(&create_lock);
for (;;) {
struct ucall uc;
vcpu_run(vcpu);
TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_IO);
switch (get_ucall(vcpu, &uc)) {
case UCALL_DONE:
goto out;
case UCALL_SYNC:
printf("Guest %d sync %lx %lx %ld\n", vcpu->id,
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[])
{
TEST_REQUIRE(kvm_has_cap(KVM_CAP_VM_TSC_CONTROL));
vm = vm_create(NR_TEST_VCPUS);
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;
}
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