blob: 1954b964d1cf1d95efd067c9f8adc11c445f2d6c [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* KVM dirty page logging performance test
*
* Based on dirty_log_test.c
*
* Copyright (C) 2018, Red Hat, Inc.
* Copyright (C) 2020, Google, Inc.
*/
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <pthread.h>
#include <linux/bitmap.h>
#include "kvm_util.h"
#include "test_util.h"
#include "perf_test_util.h"
#include "guest_modes.h"
/* How many host loops to run by default (one KVM_GET_DIRTY_LOG for each loop)*/
#define TEST_HOST_LOOP_N 2UL
static int nr_vcpus = 1;
static uint64_t guest_percpu_mem_size = DEFAULT_PER_VCPU_MEM_SIZE;
/* Host variables */
static u64 dirty_log_manual_caps;
static bool host_quit;
static int iteration;
static int vcpu_last_completed_iteration[KVM_MAX_VCPUS];
static void vcpu_worker(struct perf_test_vcpu_args *vcpu_args)
{
int ret;
struct kvm_vm *vm = perf_test_args.vm;
uint64_t pages_count = 0;
struct kvm_run *run;
struct timespec start;
struct timespec ts_diff;
struct timespec total = (struct timespec){0};
struct timespec avg;
int vcpu_id = vcpu_args->vcpu_id;
run = vcpu_state(vm, vcpu_id);
while (!READ_ONCE(host_quit)) {
int current_iteration = READ_ONCE(iteration);
clock_gettime(CLOCK_MONOTONIC, &start);
ret = _vcpu_run(vm, vcpu_id);
ts_diff = timespec_elapsed(start);
TEST_ASSERT(ret == 0, "vcpu_run failed: %d\n", ret);
TEST_ASSERT(get_ucall(vm, vcpu_id, NULL) == UCALL_SYNC,
"Invalid guest sync status: exit_reason=%s\n",
exit_reason_str(run->exit_reason));
pr_debug("Got sync event from vCPU %d\n", vcpu_id);
vcpu_last_completed_iteration[vcpu_id] = current_iteration;
pr_debug("vCPU %d updated last completed iteration to %d\n",
vcpu_id, vcpu_last_completed_iteration[vcpu_id]);
if (current_iteration) {
pages_count += vcpu_args->pages;
total = timespec_add(total, ts_diff);
pr_debug("vCPU %d iteration %d dirty memory time: %ld.%.9lds\n",
vcpu_id, current_iteration, ts_diff.tv_sec,
ts_diff.tv_nsec);
} else {
pr_debug("vCPU %d iteration %d populate memory time: %ld.%.9lds\n",
vcpu_id, current_iteration, ts_diff.tv_sec,
ts_diff.tv_nsec);
}
while (current_iteration == READ_ONCE(iteration) &&
!READ_ONCE(host_quit)) {}
}
avg = timespec_div(total, vcpu_last_completed_iteration[vcpu_id]);
pr_debug("\nvCPU %d dirtied 0x%lx pages over %d iterations in %ld.%.9lds. (Avg %ld.%.9lds/iteration)\n",
vcpu_id, pages_count, vcpu_last_completed_iteration[vcpu_id],
total.tv_sec, total.tv_nsec, avg.tv_sec, avg.tv_nsec);
}
struct test_params {
unsigned long iterations;
uint64_t phys_offset;
int wr_fract;
bool partition_vcpu_memory_access;
enum vm_mem_backing_src_type backing_src;
int slots;
};
static void toggle_dirty_logging(struct kvm_vm *vm, int slots, bool enable)
{
int i;
for (i = 0; i < slots; i++) {
int slot = PERF_TEST_MEM_SLOT_INDEX + i;
int flags = enable ? KVM_MEM_LOG_DIRTY_PAGES : 0;
vm_mem_region_set_flags(vm, slot, flags);
}
}
static inline void enable_dirty_logging(struct kvm_vm *vm, int slots)
{
toggle_dirty_logging(vm, slots, true);
}
static inline void disable_dirty_logging(struct kvm_vm *vm, int slots)
{
toggle_dirty_logging(vm, slots, false);
}
static void get_dirty_log(struct kvm_vm *vm, unsigned long *bitmaps[], int slots)
{
int i;
for (i = 0; i < slots; i++) {
int slot = PERF_TEST_MEM_SLOT_INDEX + i;
kvm_vm_get_dirty_log(vm, slot, bitmaps[i]);
}
}
static void clear_dirty_log(struct kvm_vm *vm, unsigned long *bitmaps[],
int slots, uint64_t pages_per_slot)
{
int i;
for (i = 0; i < slots; i++) {
int slot = PERF_TEST_MEM_SLOT_INDEX + i;
kvm_vm_clear_dirty_log(vm, slot, bitmaps[i], 0, pages_per_slot);
}
}
static unsigned long **alloc_bitmaps(int slots, uint64_t pages_per_slot)
{
unsigned long **bitmaps;
int i;
bitmaps = malloc(slots * sizeof(bitmaps[0]));
TEST_ASSERT(bitmaps, "Failed to allocate bitmaps array.");
for (i = 0; i < slots; i++) {
bitmaps[i] = bitmap_zalloc(pages_per_slot);
TEST_ASSERT(bitmaps[i], "Failed to allocate slot bitmap.");
}
return bitmaps;
}
static void free_bitmaps(unsigned long *bitmaps[], int slots)
{
int i;
for (i = 0; i < slots; i++)
free(bitmaps[i]);
free(bitmaps);
}
static void run_test(enum vm_guest_mode mode, void *arg)
{
struct test_params *p = arg;
struct kvm_vm *vm;
unsigned long **bitmaps;
uint64_t guest_num_pages;
uint64_t host_num_pages;
uint64_t pages_per_slot;
int vcpu_id;
struct timespec start;
struct timespec ts_diff;
struct timespec get_dirty_log_total = (struct timespec){0};
struct timespec vcpu_dirty_total = (struct timespec){0};
struct timespec avg;
struct kvm_enable_cap cap = {};
struct timespec clear_dirty_log_total = (struct timespec){0};
vm = perf_test_create_vm(mode, nr_vcpus, guest_percpu_mem_size,
p->slots, p->backing_src,
p->partition_vcpu_memory_access);
perf_test_set_wr_fract(vm, p->wr_fract);
guest_num_pages = (nr_vcpus * guest_percpu_mem_size) >> vm_get_page_shift(vm);
guest_num_pages = vm_adjust_num_guest_pages(mode, guest_num_pages);
host_num_pages = vm_num_host_pages(mode, guest_num_pages);
pages_per_slot = host_num_pages / p->slots;
bitmaps = alloc_bitmaps(p->slots, pages_per_slot);
if (dirty_log_manual_caps) {
cap.cap = KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2;
cap.args[0] = dirty_log_manual_caps;
vm_enable_cap(vm, &cap);
}
/* Start the iterations */
iteration = 0;
host_quit = false;
clock_gettime(CLOCK_MONOTONIC, &start);
for (vcpu_id = 0; vcpu_id < nr_vcpus; vcpu_id++)
vcpu_last_completed_iteration[vcpu_id] = -1;
perf_test_start_vcpu_threads(nr_vcpus, vcpu_worker);
/* Allow the vCPUs to populate memory */
pr_debug("Starting iteration %d - Populating\n", iteration);
for (vcpu_id = 0; vcpu_id < nr_vcpus; vcpu_id++) {
while (READ_ONCE(vcpu_last_completed_iteration[vcpu_id]) !=
iteration)
;
}
ts_diff = timespec_elapsed(start);
pr_info("Populate memory time: %ld.%.9lds\n",
ts_diff.tv_sec, ts_diff.tv_nsec);
/* Enable dirty logging */
clock_gettime(CLOCK_MONOTONIC, &start);
enable_dirty_logging(vm, p->slots);
ts_diff = timespec_elapsed(start);
pr_info("Enabling dirty logging time: %ld.%.9lds\n\n",
ts_diff.tv_sec, ts_diff.tv_nsec);
while (iteration < p->iterations) {
/*
* Incrementing the iteration number will start the vCPUs
* dirtying memory again.
*/
clock_gettime(CLOCK_MONOTONIC, &start);
iteration++;
pr_debug("Starting iteration %d\n", iteration);
for (vcpu_id = 0; vcpu_id < nr_vcpus; vcpu_id++) {
while (READ_ONCE(vcpu_last_completed_iteration[vcpu_id])
!= iteration)
;
}
ts_diff = timespec_elapsed(start);
vcpu_dirty_total = timespec_add(vcpu_dirty_total, ts_diff);
pr_info("Iteration %d dirty memory time: %ld.%.9lds\n",
iteration, ts_diff.tv_sec, ts_diff.tv_nsec);
clock_gettime(CLOCK_MONOTONIC, &start);
get_dirty_log(vm, bitmaps, p->slots);
ts_diff = timespec_elapsed(start);
get_dirty_log_total = timespec_add(get_dirty_log_total,
ts_diff);
pr_info("Iteration %d get dirty log time: %ld.%.9lds\n",
iteration, ts_diff.tv_sec, ts_diff.tv_nsec);
if (dirty_log_manual_caps) {
clock_gettime(CLOCK_MONOTONIC, &start);
clear_dirty_log(vm, bitmaps, p->slots, pages_per_slot);
ts_diff = timespec_elapsed(start);
clear_dirty_log_total = timespec_add(clear_dirty_log_total,
ts_diff);
pr_info("Iteration %d clear dirty log time: %ld.%.9lds\n",
iteration, ts_diff.tv_sec, ts_diff.tv_nsec);
}
}
/* Disable dirty logging */
clock_gettime(CLOCK_MONOTONIC, &start);
disable_dirty_logging(vm, p->slots);
ts_diff = timespec_elapsed(start);
pr_info("Disabling dirty logging time: %ld.%.9lds\n",
ts_diff.tv_sec, ts_diff.tv_nsec);
/* Tell the vcpu thread to quit */
host_quit = true;
perf_test_join_vcpu_threads(nr_vcpus);
avg = timespec_div(get_dirty_log_total, p->iterations);
pr_info("Get dirty log over %lu iterations took %ld.%.9lds. (Avg %ld.%.9lds/iteration)\n",
p->iterations, get_dirty_log_total.tv_sec,
get_dirty_log_total.tv_nsec, avg.tv_sec, avg.tv_nsec);
if (dirty_log_manual_caps) {
avg = timespec_div(clear_dirty_log_total, p->iterations);
pr_info("Clear dirty log over %lu iterations took %ld.%.9lds. (Avg %ld.%.9lds/iteration)\n",
p->iterations, clear_dirty_log_total.tv_sec,
clear_dirty_log_total.tv_nsec, avg.tv_sec, avg.tv_nsec);
}
free_bitmaps(bitmaps, p->slots);
perf_test_destroy_vm(vm);
}
static void help(char *name)
{
puts("");
printf("usage: %s [-h] [-i iterations] [-p offset] "
"[-m mode] [-b vcpu bytes] [-v vcpus] [-o] [-s mem type]"
"[-x memslots]\n", name);
puts("");
printf(" -i: specify iteration counts (default: %"PRIu64")\n",
TEST_HOST_LOOP_N);
printf(" -p: specify guest physical test memory offset\n"
" Warning: a low offset can conflict with the loaded test code.\n");
guest_modes_help();
printf(" -b: specify the size of the memory region which should be\n"
" dirtied by each vCPU. e.g. 10M or 3G.\n"
" (default: 1G)\n");
printf(" -f: specify the fraction of pages which should be written to\n"
" as opposed to simply read, in the form\n"
" 1/<fraction of pages to write>.\n"
" (default: 1 i.e. all pages are written to.)\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");
backing_src_help("-s");
printf(" -x: Split the memory region into this number of memslots.\n"
" (default: 1)\n");
puts("");
exit(0);
}
int main(int argc, char *argv[])
{
int max_vcpus = kvm_check_cap(KVM_CAP_MAX_VCPUS);
struct test_params p = {
.iterations = TEST_HOST_LOOP_N,
.wr_fract = 1,
.partition_vcpu_memory_access = true,
.backing_src = DEFAULT_VM_MEM_SRC,
.slots = 1,
};
int opt;
dirty_log_manual_caps =
kvm_check_cap(KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2);
dirty_log_manual_caps &= (KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE |
KVM_DIRTY_LOG_INITIALLY_SET);
guest_modes_append_default();
while ((opt = getopt(argc, argv, "hi:p:m:b:f:v:os:x:")) != -1) {
switch (opt) {
case 'i':
p.iterations = atoi(optarg);
break;
case 'p':
p.phys_offset = strtoull(optarg, NULL, 0);
break;
case 'm':
guest_modes_cmdline(optarg);
break;
case 'b':
guest_percpu_mem_size = parse_size(optarg);
break;
case 'f':
p.wr_fract = atoi(optarg);
TEST_ASSERT(p.wr_fract >= 1,
"Write fraction cannot be less than one");
break;
case 'v':
nr_vcpus = atoi(optarg);
TEST_ASSERT(nr_vcpus > 0 && 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 's':
p.backing_src = parse_backing_src_type(optarg);
break;
case 'x':
p.slots = atoi(optarg);
break;
case 'h':
default:
help(argv[0]);
break;
}
}
TEST_ASSERT(p.iterations >= 2, "The test should have at least two iterations");
pr_info("Test iterations: %"PRIu64"\n", p.iterations);
for_each_guest_mode(run_test, &p);
return 0;
}