// SPDX-License-Identifier: GPL-2.0
/*
* KVM memslot modification stress test
* Adapted from demand_paging_test.c
*
* Copyright (C) 2018, Red Hat, Inc.
* Copyright (C) 2020, Google, Inc.
*/
#include <stdio.h>
#include <stdlib.h>
#include <sys/syscall.h>
#include <unistd.h>
#include <asm/unistd.h>
#include <time.h>
#include <poll.h>
#include <pthread.h>
#include <linux/bitmap.h>
#include <linux/bitops.h>
#include <linux/userfaultfd.h>
#include "memstress.h"
#include "processor.h"
#include "test_util.h"
#include "guest_modes.h"
#define DUMMY_MEMSLOT_INDEX 7
#define DEFAULT_MEMSLOT_MODIFICATION_ITERATIONS 10
static int nr_vcpus = 1;
static uint64_t guest_percpu_mem_size = DEFAULT_PER_VCPU_MEM_SIZE;
static void vcpu_worker(struct memstress_vcpu_args *vcpu_args)
{
struct kvm_vcpu *vcpu = vcpu_args->vcpu;
struct kvm_run *run;
int ret;
run = vcpu->run;
/* Let the guest access its memory until a stop signal is received */
while (!READ_ONCE(memstress_args.stop_vcpus)) {
ret = _vcpu_run(vcpu);
TEST_ASSERT(ret == 0, "vcpu_run failed: %d", ret);
if (get_ucall(vcpu, NULL) == UCALL_SYNC)
continue;
TEST_ASSERT(false,
"Invalid guest sync status: exit_reason=%s\n",
exit_reason_str(run->exit_reason));
}
}
static void add_remove_memslot(struct kvm_vm *vm, useconds_t delay,
uint64_t nr_modifications)
{
uint64_t pages = max_t(int, vm->page_size, getpagesize()) / vm->page_size;
uint64_t gpa;
int i;
/*
* Add the dummy memslot just below the memstress memslot, which is
* at the top of the guest physical address space.
*/
gpa = memstress_args.gpa - pages * vm->page_size;
for (i = 0; i < nr_modifications; i++) {
usleep(delay);
vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, gpa,
DUMMY_MEMSLOT_INDEX, pages, 0);
vm_mem_region_delete(vm, DUMMY_MEMSLOT_INDEX);
}
}
struct test_params {
useconds_t delay;
uint64_t nr_iterations;
bool partition_vcpu_memory_access;
bool disable_slot_zap_quirk;
};
static void run_test(enum vm_guest_mode mode, void *arg)
{
struct test_params *p = arg;
struct kvm_vm *vm;
vm = memstress_create_vm(mode, nr_vcpus, guest_percpu_mem_size, 1,
VM_MEM_SRC_ANONYMOUS,
p->partition_vcpu_memory_access);
#ifdef __x86_64__
if (p->disable_slot_zap_quirk)
vm_enable_cap(vm, KVM_CAP_DISABLE_QUIRKS2, KVM_X86_QUIRK_SLOT_ZAP_ALL);
pr_info("Memslot zap quirk %s\n", p->disable_slot_zap_quirk ?
"disabled" : "enabled");
#endif
pr_info("Finished creating vCPUs\n");
memstress_start_vcpu_threads(nr_vcpus, vcpu_worker);
pr_info("Started all vCPUs\n");
add_remove_memslot(vm, p->delay, p->nr_iterations);
memstress_join_vcpu_threads(nr_vcpus);
pr_info("All vCPU threads joined\n");
memstress_destroy_vm(vm);
}
static void help(char *name)
{
puts("");
printf("usage: %s [-h] [-m mode] [-d delay_usec] [-q]\n"
" [-b memory] [-v vcpus] [-o] [-i iterations]\n", name);
guest_modes_help();
printf(" -d: add a delay between each iteration of adding and\n"
" deleting a memslot in usec.\n");
printf(" -q: Disable memslot zap quirk.\n");
printf(" -b: specify the size of the memory region which should be\n"
" accessed by each vCPU. e.g. 10M or 3G.\n"
" Default: 1G\n");
printf(" -v: specify the number of vCPUs to run.\n");
printf(" -o: Overlap guest memory accesses instead of partitioning\n"
" them into a separate region of memory for each vCPU.\n");
printf(" -i: specify the number of iterations of adding and removing\n"
" a memslot.\n"
" Default: %d\n", DEFAULT_MEMSLOT_MODIFICATION_ITERATIONS);
puts("");
exit(0);
}
int main(int argc, char *argv[])
{
int max_vcpus = kvm_check_cap(KVM_CAP_MAX_VCPUS);
int opt;
struct test_params p = {
.delay = 0,
.nr_iterations = DEFAULT_MEMSLOT_MODIFICATION_ITERATIONS,
.partition_vcpu_memory_access = true
};
guest_modes_append_default();
while ((opt = getopt(argc, argv, "hm:d:qb:v:oi:")) != -1) {
switch (opt) {
case 'm':
guest_modes_cmdline(optarg);
break;
case 'd':
p.delay = atoi_non_negative("Delay", optarg);
break;
case 'b':
guest_percpu_mem_size = parse_size(optarg);
break;
case 'v':
nr_vcpus = atoi_positive("Number of vCPUs", optarg);
TEST_ASSERT(nr_vcpus <= max_vcpus,
"Invalid number of vcpus, must be between 1 and %d",
max_vcpus);
break;
case 'o':
p.partition_vcpu_memory_access = false;
break;
case 'i':
p.nr_iterations = atoi_positive("Number of iterations", optarg);
break;
case 'q':
p.disable_slot_zap_quirk = true;
TEST_REQUIRE(kvm_check_cap(KVM_CAP_DISABLE_QUIRKS2) &
KVM_X86_QUIRK_SLOT_ZAP_ALL);
break;
case 'h':
default:
help(argv[0]);
break;
}
}
for_each_guest_mode(run_test, &p);
return 0;
}