summaryrefslogtreecommitdiffstats
path: root/tools/testing/selftests/kvm/dirty_log_test.c
diff options
context:
space:
mode:
Diffstat (limited to 'tools/testing/selftests/kvm/dirty_log_test.c')
-rw-r--r--tools/testing/selftests/kvm/dirty_log_test.c448
1 files changed, 448 insertions, 0 deletions
diff --git a/tools/testing/selftests/kvm/dirty_log_test.c b/tools/testing/selftests/kvm/dirty_log_test.c
new file mode 100644
index 000000000000..aeff95a91b15
--- /dev/null
+++ b/tools/testing/selftests/kvm/dirty_log_test.c
@@ -0,0 +1,448 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * KVM dirty page logging test
+ *
+ * Copyright (C) 2018, Red Hat, Inc.
+ */
+
+#define _GNU_SOURCE /* for program_invocation_name */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <time.h>
+#include <pthread.h>
+#include <linux/bitmap.h>
+#include <linux/bitops.h>
+
+#include "test_util.h"
+#include "kvm_util.h"
+#include "processor.h"
+
+#define DEBUG printf
+
+#define VCPU_ID 1
+
+/* The memory slot index to track dirty pages */
+#define TEST_MEM_SLOT_INDEX 1
+
+/* Default guest test memory offset, 1G */
+#define DEFAULT_GUEST_TEST_MEM 0x40000000
+
+/* How many pages to dirty for each guest loop */
+#define TEST_PAGES_PER_LOOP 1024
+
+/* How many host loops to run (one KVM_GET_DIRTY_LOG for each loop) */
+#define TEST_HOST_LOOP_N 32UL
+
+/* Interval for each host loop (ms) */
+#define TEST_HOST_LOOP_INTERVAL 10UL
+
+/*
+ * Guest/Host shared variables. Ensure addr_gva2hva() and/or
+ * sync_global_to/from_guest() are used when accessing from
+ * the host. READ/WRITE_ONCE() should also be used with anything
+ * that may change.
+ */
+static uint64_t host_page_size;
+static uint64_t guest_page_size;
+static uint64_t guest_num_pages;
+static uint64_t random_array[TEST_PAGES_PER_LOOP];
+static uint64_t iteration;
+
+/*
+ * GPA offset of the testing memory slot. Must be bigger than
+ * DEFAULT_GUEST_PHY_PAGES.
+ */
+static uint64_t guest_test_mem = DEFAULT_GUEST_TEST_MEM;
+
+/*
+ * Continuously write to the first 8 bytes of a random pages within
+ * the testing memory region.
+ */
+static void guest_code(void)
+{
+ int i;
+
+ while (true) {
+ for (i = 0; i < TEST_PAGES_PER_LOOP; i++) {
+ uint64_t addr = guest_test_mem;
+ addr += (READ_ONCE(random_array[i]) % guest_num_pages)
+ * guest_page_size;
+ addr &= ~(host_page_size - 1);
+ *(uint64_t *)addr = READ_ONCE(iteration);
+ }
+
+ /* Tell the host that we need more random numbers */
+ GUEST_SYNC(1);
+ }
+}
+
+/* Host variables */
+static bool host_quit;
+
+/* Points to the test VM memory region on which we track dirty logs */
+static void *host_test_mem;
+static uint64_t host_num_pages;
+
+/* For statistics only */
+static uint64_t host_dirty_count;
+static uint64_t host_clear_count;
+static uint64_t host_track_next_count;
+
+/*
+ * We use this bitmap to track some pages that should have its dirty
+ * bit set in the _next_ iteration. For example, if we detected the
+ * page value changed to current iteration but at the same time the
+ * page bit is cleared in the latest bitmap, then the system must
+ * report that write in the next get dirty log call.
+ */
+static unsigned long *host_bmap_track;
+
+static void generate_random_array(uint64_t *guest_array, uint64_t size)
+{
+ uint64_t i;
+
+ for (i = 0; i < size; i++)
+ guest_array[i] = random();
+}
+
+static void *vcpu_worker(void *data)
+{
+ int ret;
+ struct kvm_vm *vm = data;
+ uint64_t *guest_array;
+ uint64_t pages_count = 0;
+ struct kvm_run *run;
+ struct ucall uc;
+
+ run = vcpu_state(vm, VCPU_ID);
+
+ guest_array = addr_gva2hva(vm, (vm_vaddr_t)random_array);
+ generate_random_array(guest_array, TEST_PAGES_PER_LOOP);
+
+ while (!READ_ONCE(host_quit)) {
+ /* Let the guest dirty the random pages */
+ ret = _vcpu_run(vm, VCPU_ID);
+ if (get_ucall(vm, VCPU_ID, &uc) == UCALL_SYNC) {
+ pages_count += TEST_PAGES_PER_LOOP;
+ generate_random_array(guest_array, TEST_PAGES_PER_LOOP);
+ } else {
+ TEST_ASSERT(false,
+ "Invalid guest sync status: "
+ "exit_reason=%s\n",
+ exit_reason_str(run->exit_reason));
+ }
+ }
+
+ DEBUG("Dirtied %"PRIu64" pages\n", pages_count);
+
+ return NULL;
+}
+
+static void vm_dirty_log_verify(unsigned long *bmap)
+{
+ uint64_t page;
+ uint64_t *value_ptr;
+ uint64_t step = host_page_size >= guest_page_size ? 1 :
+ guest_page_size / host_page_size;
+
+ for (page = 0; page < host_num_pages; page += step) {
+ value_ptr = host_test_mem + page * host_page_size;
+
+ /* If this is a special page that we were tracking... */
+ if (test_and_clear_bit(page, host_bmap_track)) {
+ host_track_next_count++;
+ TEST_ASSERT(test_bit(page, bmap),
+ "Page %"PRIu64" should have its dirty bit "
+ "set in this iteration but it is missing",
+ page);
+ }
+
+ if (test_bit(page, bmap)) {
+ host_dirty_count++;
+ /*
+ * If the bit is set, the value written onto
+ * the corresponding page should be either the
+ * previous iteration number or the current one.
+ */
+ TEST_ASSERT(*value_ptr == iteration ||
+ *value_ptr == iteration - 1,
+ "Set page %"PRIu64" value %"PRIu64
+ " incorrect (iteration=%"PRIu64")",
+ page, *value_ptr, iteration);
+ } else {
+ host_clear_count++;
+ /*
+ * If cleared, the value written can be any
+ * value smaller or equals to the iteration
+ * number. Note that the value can be exactly
+ * (iteration-1) if that write can happen
+ * like this:
+ *
+ * (1) increase loop count to "iteration-1"
+ * (2) write to page P happens (with value
+ * "iteration-1")
+ * (3) get dirty log for "iteration-1"; we'll
+ * see that page P bit is set (dirtied),
+ * and not set the bit in host_bmap_track
+ * (4) increase loop count to "iteration"
+ * (which is current iteration)
+ * (5) get dirty log for current iteration,
+ * we'll see that page P is cleared, with
+ * value "iteration-1".
+ */
+ TEST_ASSERT(*value_ptr <= iteration,
+ "Clear page %"PRIu64" value %"PRIu64
+ " incorrect (iteration=%"PRIu64")",
+ page, *value_ptr, iteration);
+ if (*value_ptr == iteration) {
+ /*
+ * This page is _just_ modified; it
+ * should report its dirtyness in the
+ * next run
+ */
+ set_bit(page, host_bmap_track);
+ }
+ }
+ }
+}
+
+static struct kvm_vm *create_vm(enum vm_guest_mode mode, uint32_t vcpuid,
+ uint64_t extra_mem_pages, void *guest_code)
+{
+ struct kvm_vm *vm;
+ uint64_t extra_pg_pages = extra_mem_pages / 512 * 2;
+
+ vm = vm_create(mode, DEFAULT_GUEST_PHY_PAGES + extra_pg_pages, O_RDWR);
+ kvm_vm_elf_load(vm, program_invocation_name, 0, 0);
+#ifdef __x86_64__
+ vm_create_irqchip(vm);
+#endif
+ vm_vcpu_add_default(vm, vcpuid, guest_code);
+ return vm;
+}
+
+static void run_test(enum vm_guest_mode mode, unsigned long iterations,
+ unsigned long interval, bool top_offset)
+{
+ unsigned int guest_pa_bits, guest_page_shift;
+ pthread_t vcpu_thread;
+ struct kvm_vm *vm;
+ uint64_t max_gfn;
+ unsigned long *bmap;
+
+ switch (mode) {
+ case VM_MODE_P52V48_4K:
+ guest_pa_bits = 52;
+ guest_page_shift = 12;
+ break;
+ case VM_MODE_P52V48_64K:
+ guest_pa_bits = 52;
+ guest_page_shift = 16;
+ break;
+ case VM_MODE_P40V48_4K:
+ guest_pa_bits = 40;
+ guest_page_shift = 12;
+ break;
+ case VM_MODE_P40V48_64K:
+ guest_pa_bits = 40;
+ guest_page_shift = 16;
+ break;
+ default:
+ TEST_ASSERT(false, "Unknown guest mode, mode: 0x%x", mode);
+ }
+
+ DEBUG("Testing guest mode: %s\n", vm_guest_mode_string(mode));
+
+ max_gfn = (1ul << (guest_pa_bits - guest_page_shift)) - 1;
+ guest_page_size = (1ul << guest_page_shift);
+ /* 1G of guest page sized pages */
+ guest_num_pages = (1ul << (30 - guest_page_shift));
+ host_page_size = getpagesize();
+ host_num_pages = (guest_num_pages * guest_page_size) / host_page_size +
+ !!((guest_num_pages * guest_page_size) % host_page_size);
+
+ if (top_offset) {
+ guest_test_mem = (max_gfn - guest_num_pages) * guest_page_size;
+ guest_test_mem &= ~(host_page_size - 1);
+ }
+
+ DEBUG("guest test mem offset: 0x%lx\n", guest_test_mem);
+
+ bmap = bitmap_alloc(host_num_pages);
+ host_bmap_track = bitmap_alloc(host_num_pages);
+
+ vm = create_vm(mode, VCPU_ID, guest_num_pages, guest_code);
+
+ /* Add an extra memory slot for testing dirty logging */
+ vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS,
+ guest_test_mem,
+ TEST_MEM_SLOT_INDEX,
+ guest_num_pages,
+ KVM_MEM_LOG_DIRTY_PAGES);
+
+ /* Do 1:1 mapping for the dirty track memory slot */
+ virt_map(vm, guest_test_mem, guest_test_mem,
+ guest_num_pages * guest_page_size, 0);
+
+ /* Cache the HVA pointer of the region */
+ host_test_mem = addr_gpa2hva(vm, (vm_paddr_t)guest_test_mem);
+
+#ifdef __x86_64__
+ vcpu_set_cpuid(vm, VCPU_ID, kvm_get_supported_cpuid());
+#endif
+#ifdef __aarch64__
+ ucall_init(vm, UCALL_MMIO, NULL);
+#endif
+
+ /* Export the shared variables to the guest */
+ sync_global_to_guest(vm, host_page_size);
+ sync_global_to_guest(vm, guest_page_size);
+ sync_global_to_guest(vm, guest_test_mem);
+ sync_global_to_guest(vm, guest_num_pages);
+
+ /* Start the iterations */
+ iteration = 1;
+ sync_global_to_guest(vm, iteration);
+ host_quit = false;
+ host_dirty_count = 0;
+ host_clear_count = 0;
+ host_track_next_count = 0;
+
+ pthread_create(&vcpu_thread, NULL, vcpu_worker, vm);
+
+ while (iteration < iterations) {
+ /* Give the vcpu thread some time to dirty some pages */
+ usleep(interval * 1000);
+ kvm_vm_get_dirty_log(vm, TEST_MEM_SLOT_INDEX, bmap);
+ vm_dirty_log_verify(bmap);
+ iteration++;
+ sync_global_to_guest(vm, iteration);
+ }
+
+ /* Tell the vcpu thread to quit */
+ host_quit = true;
+ pthread_join(vcpu_thread, NULL);
+
+ DEBUG("Total bits checked: dirty (%"PRIu64"), clear (%"PRIu64"), "
+ "track_next (%"PRIu64")\n", host_dirty_count, host_clear_count,
+ host_track_next_count);
+
+ free(bmap);
+ free(host_bmap_track);
+ ucall_uninit(vm);
+ kvm_vm_free(vm);
+}
+
+static struct vm_guest_modes {
+ enum vm_guest_mode mode;
+ bool supported;
+ bool enabled;
+} vm_guest_modes[NUM_VM_MODES] = {
+#if defined(__x86_64__)
+ { VM_MODE_P52V48_4K, 1, 1, },
+ { VM_MODE_P52V48_64K, 0, 0, },
+ { VM_MODE_P40V48_4K, 0, 0, },
+ { VM_MODE_P40V48_64K, 0, 0, },
+#elif defined(__aarch64__)
+ { VM_MODE_P52V48_4K, 0, 0, },
+ { VM_MODE_P52V48_64K, 0, 0, },
+ { VM_MODE_P40V48_4K, 1, 1, },
+ { VM_MODE_P40V48_64K, 1, 1, },
+#endif
+};
+
+static void help(char *name)
+{
+ int i;
+
+ puts("");
+ printf("usage: %s [-h] [-i iterations] [-I interval] "
+ "[-o offset] [-t] [-m mode]\n", name);
+ puts("");
+ printf(" -i: specify iteration counts (default: %"PRIu64")\n",
+ TEST_HOST_LOOP_N);
+ printf(" -I: specify interval in ms (default: %"PRIu64" ms)\n",
+ TEST_HOST_LOOP_INTERVAL);
+ printf(" -o: guest test memory offset (default: 0x%lx)\n",
+ DEFAULT_GUEST_TEST_MEM);
+ printf(" -t: map guest test memory at the top of the allowed "
+ "physical address range\n");
+ printf(" -m: specify the guest mode ID to test "
+ "(default: test all supported modes)\n"
+ " This option may be used multiple times.\n"
+ " Guest mode IDs:\n");
+ for (i = 0; i < NUM_VM_MODES; ++i) {
+ printf(" %d: %s%s\n",
+ vm_guest_modes[i].mode,
+ vm_guest_mode_string(vm_guest_modes[i].mode),
+ vm_guest_modes[i].supported ? " (supported)" : "");
+ }
+ puts("");
+ exit(0);
+}
+
+int main(int argc, char *argv[])
+{
+ unsigned long iterations = TEST_HOST_LOOP_N;
+ unsigned long interval = TEST_HOST_LOOP_INTERVAL;
+ bool mode_selected = false;
+ bool top_offset = false;
+ unsigned int mode;
+ int opt, i;
+
+ while ((opt = getopt(argc, argv, "hi:I:o:tm:")) != -1) {
+ switch (opt) {
+ case 'i':
+ iterations = strtol(optarg, NULL, 10);
+ break;
+ case 'I':
+ interval = strtol(optarg, NULL, 10);
+ break;
+ case 'o':
+ guest_test_mem = strtoull(optarg, NULL, 0);
+ break;
+ case 't':
+ top_offset = true;
+ break;
+ case 'm':
+ if (!mode_selected) {
+ for (i = 0; i < NUM_VM_MODES; ++i)
+ vm_guest_modes[i].enabled = 0;
+ mode_selected = true;
+ }
+ mode = strtoul(optarg, NULL, 10);
+ TEST_ASSERT(mode < NUM_VM_MODES,
+ "Guest mode ID %d too big", mode);
+ vm_guest_modes[mode].enabled = 1;
+ break;
+ case 'h':
+ default:
+ help(argv[0]);
+ break;
+ }
+ }
+
+ TEST_ASSERT(iterations > 2, "Iterations must be greater than two");
+ TEST_ASSERT(interval > 0, "Interval must be greater than zero");
+ TEST_ASSERT(!top_offset || guest_test_mem == DEFAULT_GUEST_TEST_MEM,
+ "Cannot use both -o [offset] and -t at the same time");
+
+ DEBUG("Test iterations: %"PRIu64", interval: %"PRIu64" (ms)\n",
+ iterations, interval);
+
+ srandom(time(0));
+
+ for (i = 0; i < NUM_VM_MODES; ++i) {
+ if (!vm_guest_modes[i].enabled)
+ continue;
+ TEST_ASSERT(vm_guest_modes[i].supported,
+ "Guest mode ID %d (%s) not supported.",
+ vm_guest_modes[i].mode,
+ vm_guest_mode_string(vm_guest_modes[i].mode));
+ run_test(vm_guest_modes[i].mode, iterations, interval, top_offset);
+ }
+
+ return 0;
+}
OpenPOWER on IntegriCloud