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// 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 <pthread.h>
#include <semaphore.h>
#include <sys/types.h>
#include <signal.h>
#include <errno.h>
#include <linux/bitmap.h>
#include <linux/bitops.h>
#include <linux/atomic.h>
#include <asm/barrier.h>
#include "kvm_util.h"
#include "test_util.h"
#include "guest_modes.h"
#include "processor.h"
/* The memory slot index to track dirty pages */
#define TEST_MEM_SLOT_INDEX 1
/* Default guest test virtual memory offset */
#define DEFAULT_GUEST_TEST_MEM 0xc0000000
/* 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
/* Dirty bitmaps are always little endian, so we need to swap on big endian */
#if defined(__s390x__)
# define BITOP_LE_SWIZZLE ((BITS_PER_LONG-1) & ~0x7)
# define test_bit_le(nr, addr) \
test_bit((nr) ^ BITOP_LE_SWIZZLE, addr)
# define __set_bit_le(nr, addr) \
__set_bit((nr) ^ BITOP_LE_SWIZZLE, addr)
# define __clear_bit_le(nr, addr) \
__clear_bit((nr) ^ BITOP_LE_SWIZZLE, addr)
# define __test_and_set_bit_le(nr, addr) \
__test_and_set_bit((nr) ^ BITOP_LE_SWIZZLE, addr)
# define __test_and_clear_bit_le(nr, addr) \
__test_and_clear_bit((nr) ^ BITOP_LE_SWIZZLE, addr)
#else
# define test_bit_le test_bit
# define __set_bit_le __set_bit
# define __clear_bit_le __clear_bit
# define __test_and_set_bit_le __test_and_set_bit
# define __test_and_clear_bit_le __test_and_clear_bit
#endif
#define TEST_DIRTY_RING_COUNT 65536
#define SIG_IPI SIGUSR1
/*
* 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;
/*
* Guest physical memory offset of the testing memory slot.
* This will be set to the topmost valid physical address minus
* the test memory size.
*/
static uint64_t guest_test_phys_mem;
/*
* Guest virtual memory offset of the testing memory slot.
* Must not conflict with identity mapped test code.
*/
static uint64_t guest_test_virt_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)
{
uint64_t addr;
int i;
/*
* On s390x, all pages of a 1M segment are initially marked as dirty
* when a page of the segment is written to for the very first time.
* To compensate this specialty in this test, we need to touch all
* pages during the first iteration.
*/
for (i = 0; i < guest_num_pages; i++) {
addr = guest_test_virt_mem + i * guest_page_size;
*(uint64_t *)addr = READ_ONCE(iteration);
}
while (true) {
for (i = 0; i < TEST_PAGES_PER_LOOP; i++) {
addr = guest_test_virt_mem;
addr += (READ_ONCE(random_array[i]) % guest_num_pages)
* guest_page_size;
addr = align_down(addr, host_page_size);
*(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;
/* Whether dirty ring reset is requested, or finished */
static sem_t sem_vcpu_stop;
static sem_t sem_vcpu_cont;
/*
* This is only set by main thread, and only cleared by vcpu thread. It is
* used to request vcpu thread to stop at the next GUEST_SYNC, since GUEST_SYNC
* is the only place that we'll guarantee both "dirty bit" and "dirty data"
* will match. E.g., SIG_IPI won't guarantee that if the vcpu is interrupted
* after setting dirty bit but before the data is written.
*/
static atomic_t vcpu_sync_stop_requested;
/*
* This is updated by the vcpu thread to tell the host whether it's a
* ring-full event. It should only be read until a sem_wait() of
* sem_vcpu_stop and before vcpu continues to run.
*/
static bool dirty_ring_vcpu_ring_full;
/*
* This is only used for verifying the dirty pages. Dirty ring has a very
* tricky case when the ring just got full, kvm will do userspace exit due to
* ring full. When that happens, the very last PFN is set but actually the
* data is not changed (the guest WRITE is not really applied yet), because
* we found that the dirty ring is full, refused to continue the vcpu, and
* recorded the dirty gfn with the old contents.
*
* For this specific case, it's safe to skip checking this pfn for this
* bit, because it's a redundant bit, and when the write happens later the bit
* will be set again. We use this variable to always keep track of the latest
* dirty gfn we've collected, so that if a mismatch of data found later in the
* verifying process, we let it pass.
*/
static uint64_t dirty_ring_last_page;
enum log_mode_t {
/* Only use KVM_GET_DIRTY_LOG for logging */
LOG_MODE_DIRTY_LOG = 0,
/* Use both KVM_[GET|CLEAR]_DIRTY_LOG for logging */
LOG_MODE_CLEAR_LOG = 1,
/* Use dirty ring for logging */
LOG_MODE_DIRTY_RING = 2,
LOG_MODE_NUM,
/* Run all supported modes */
LOG_MODE_ALL = LOG_MODE_NUM,
};
/* Mode of logging to test. Default is to run all supported modes */
static enum log_mode_t host_log_mode_option = LOG_MODE_ALL;
/* Logging mode for current run */
static enum log_mode_t host_log_mode;
static pthread_t vcpu_thread;
static uint32_t test_dirty_ring_count = TEST_DIRTY_RING_COUNT;
static void vcpu_kick(void)
{
pthread_kill(vcpu_thread, SIG_IPI);
}
/*
* In our test we do signal tricks, let's use a better version of
* sem_wait to avoid signal interrupts
*/
static void sem_wait_until(sem_t *sem)
{
int ret;
do
ret = sem_wait(sem);
while (ret == -1 && errno == EINTR);
}
static bool clear_log_supported(void)
{
return kvm_has_cap(KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2);
}
static void clear_log_create_vm_done(struct kvm_vm *vm)
{
u64 manual_caps;
manual_caps = kvm_check_cap(KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2);
TEST_ASSERT(manual_caps, "MANUAL_CAPS is zero!");
manual_caps &= (KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE |
KVM_DIRTY_LOG_INITIALLY_SET);
vm_enable_cap(vm, KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2, manual_caps);
}
static void dirty_log_collect_dirty_pages(struct kvm_vcpu *vcpu, int slot,
void *bitmap, uint32_t num_pages)
{
kvm_vm_get_dirty_log(vcpu->vm, slot, bitmap);
}
static void clear_log_collect_dirty_pages(struct kvm_vcpu *vcpu, int slot,
void *bitmap, uint32_t num_pages)
{
kvm_vm_get_dirty_log(vcpu->vm, slot, bitmap);
kvm_vm_clear_dirty_log(vcpu->vm, slot, bitmap, 0, num_pages);
}
/* Should only be called after a GUEST_SYNC */
static void vcpu_handle_sync_stop(void)
{
if (atomic_read(&vcpu_sync_stop_requested)) {
/* It means main thread is sleeping waiting */
atomic_set(&vcpu_sync_stop_requested, false);
sem_post(&sem_vcpu_stop);
sem_wait_until(&sem_vcpu_cont);
}
}
static void default_after_vcpu_run(struct kvm_vcpu *vcpu, int ret, int err)
{
struct kvm_run *run = vcpu->run;
TEST_ASSERT(ret == 0 || (ret == -1 && err == EINTR),
"vcpu run failed: errno=%d", err);
TEST_ASSERT(get_ucall(vcpu, NULL) == UCALL_SYNC,
"Invalid guest sync status: exit_reason=%s\n",
exit_reason_str(run->exit_reason));
vcpu_handle_sync_stop();
}
static bool dirty_ring_supported(void)
{
return (kvm_has_cap(KVM_CAP_DIRTY_LOG_RING) ||
kvm_has_cap(KVM_CAP_DIRTY_LOG_RING_ACQ_REL));
}
static void dirty_ring_create_vm_done(struct kvm_vm *vm)
{
/*
* Switch to dirty ring mode after VM creation but before any
* of the vcpu creation.
*/
vm_enable_dirty_ring(vm, test_dirty_ring_count *
sizeof(struct kvm_dirty_gfn));
}
static inline bool dirty_gfn_is_dirtied(struct kvm_dirty_gfn *gfn)
{
return smp_load_acquire(&gfn->flags) == KVM_DIRTY_GFN_F_DIRTY;
}
static inline void dirty_gfn_set_collected(struct kvm_dirty_gfn *gfn)
{
smp_store_release(&gfn->flags, KVM_DIRTY_GFN_F_RESET);
}
static uint32_t dirty_ring_collect_one(struct kvm_dirty_gfn *dirty_gfns,
int slot, void *bitmap,
uint32_t num_pages, uint32_t *fetch_index)
{
struct kvm_dirty_gfn *cur;
uint32_t count = 0;
while (true) {
cur = &dirty_gfns[*fetch_index % test_dirty_ring_count];
if (!dirty_gfn_is_dirtied(cur))
break;
TEST_ASSERT(cur->slot == slot, "Slot number didn't match: "
"%u != %u", cur->slot, slot);
TEST_ASSERT(cur->offset < num_pages, "Offset overflow: "
"0x%llx >= 0x%x", cur->offset, num_pages);
//pr_info("fetch 0x%x page %llu\n", *fetch_index, cur->offset);
__set_bit_le(cur->offset, bitmap);
dirty_ring_last_page = cur->offset;
dirty_gfn_set_collected(cur);
(*fetch_index)++;
count++;
}
return count;
}
static void dirty_ring_wait_vcpu(void)
{
/* This makes sure that hardware PML cache flushed */
vcpu_kick();
sem_wait_until(&sem_vcpu_stop);
}
static void dirty_ring_continue_vcpu(void)
{
pr_info("Notifying vcpu to continue\n");
sem_post(&sem_vcpu_cont);
}
static void dirty_ring_collect_dirty_pages(struct kvm_vcpu *vcpu, int slot,
void *bitmap, uint32_t num_pages)
{
/* We only have one vcpu */
static uint32_t fetch_index = 0;
uint32_t count = 0, cleared;
bool continued_vcpu = false;
dirty_ring_wait_vcpu();
if (!dirty_ring_vcpu_ring_full) {
/*
* This is not a ring-full event, it's safe to allow
* vcpu to continue
*/
dirty_ring_continue_vcpu();
continued_vcpu = true;
}
/* Only have one vcpu */
count = dirty_ring_collect_one(vcpu_map_dirty_ring(vcpu),
slot, bitmap, num_pages, &fetch_index);
cleared = kvm_vm_reset_dirty_ring(vcpu->vm);
/* Cleared pages should be the same as collected */
TEST_ASSERT(cleared == count, "Reset dirty pages (%u) mismatch "
"with collected (%u)", cleared, count);
if (!continued_vcpu) {
TEST_ASSERT(dirty_ring_vcpu_ring_full,
"Didn't continue vcpu even without ring full");
dirty_ring_continue_vcpu();
}
pr_info("Iteration %ld collected %u pages\n", iteration, count);
}
static void dirty_ring_after_vcpu_run(struct kvm_vcpu *vcpu, int ret, int err)
{
struct kvm_run *run = vcpu->run;
/* A ucall-sync or ring-full event is allowed */
if (get_ucall(vcpu, NULL) == UCALL_SYNC) {
/* We should allow this to continue */
;
} else if (run->exit_reason == KVM_EXIT_DIRTY_RING_FULL ||
(ret == -1 && err == EINTR)) {
/* Update the flag first before pause */
WRITE_ONCE(dirty_ring_vcpu_ring_full,
run->exit_reason == KVM_EXIT_DIRTY_RING_FULL);
sem_post(&sem_vcpu_stop);
pr_info("vcpu stops because %s...\n",
dirty_ring_vcpu_ring_full ?
"dirty ring is full" : "vcpu is kicked out");
sem_wait_until(&sem_vcpu_cont);
pr_info("vcpu continues now.\n");
} else {
TEST_ASSERT(false, "Invalid guest sync status: "
"exit_reason=%s\n",
exit_reason_str(run->exit_reason));
}
}
static void dirty_ring_before_vcpu_join(void)
{
/* Kick another round of vcpu just to make sure it will quit */
sem_post(&sem_vcpu_cont);
}
struct log_mode {
const char *name;
/* Return true if this mode is supported, otherwise false */
bool (*supported)(void);
/* Hook when the vm creation is done (before vcpu creation) */
void (*create_vm_done)(struct kvm_vm *vm);
/* Hook to collect the dirty pages into the bitmap provided */
void (*collect_dirty_pages) (struct kvm_vcpu *vcpu, int slot,
void *bitmap, uint32_t num_pages);
/* Hook to call when after each vcpu run */
void (*after_vcpu_run)(struct kvm_vcpu *vcpu, int ret, int err);
void (*before_vcpu_join) (void);
} log_modes[LOG_MODE_NUM] = {
{
.name = "dirty-log",
.collect_dirty_pages = dirty_log_collect_dirty_pages,
.after_vcpu_run = default_after_vcpu_run,
},
{
.name = "clear-log",
.supported = clear_log_supported,
.create_vm_done = clear_log_create_vm_done,
.collect_dirty_pages = clear_log_collect_dirty_pages,
.after_vcpu_run = default_after_vcpu_run,
},
{
.name = "dirty-ring",
.supported = dirty_ring_supported,
.create_vm_done = dirty_ring_create_vm_done,
.collect_dirty_pages = dirty_ring_collect_dirty_pages,
.before_vcpu_join = dirty_ring_before_vcpu_join,
.after_vcpu_run = dirty_ring_after_vcpu_run,
},
};
/*
* 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 log_modes_dump(void)
{
int i;
printf("all");
for (i = 0; i < LOG_MODE_NUM; i++)
printf(", %s", log_modes[i].name);
printf("\n");
}
static bool log_mode_supported(void)
{
struct log_mode *mode = &log_modes[host_log_mode];
if (mode->supported)
return mode->supported();
return true;
}
static void log_mode_create_vm_done(struct kvm_vm *vm)
{
struct log_mode *mode = &log_modes[host_log_mode];
if (mode->create_vm_done)
mode->create_vm_done(vm);
}
static void log_mode_collect_dirty_pages(struct kvm_vcpu *vcpu, int slot,
void *bitmap, uint32_t num_pages)
{
struct log_mode *mode = &log_modes[host_log_mode];
TEST_ASSERT(mode->collect_dirty_pages != NULL,
"collect_dirty_pages() is required for any log mode!");
mode->collect_dirty_pages(vcpu, slot, bitmap, num_pages);
}
static void log_mode_after_vcpu_run(struct kvm_vcpu *vcpu, int ret, int err)
{
struct log_mode *mode = &log_modes[host_log_mode];
if (mode->after_vcpu_run)
mode->after_vcpu_run(vcpu, ret, err);
}
static void log_mode_before_vcpu_join(void)
{
struct log_mode *mode = &log_modes[host_log_mode];
if (mode->before_vcpu_join)
mode->before_vcpu_join();
}
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_vcpu *vcpu = data;
struct kvm_vm *vm = vcpu->vm;
uint64_t *guest_array;
uint64_t pages_count = 0;
struct kvm_signal_mask *sigmask = alloca(offsetof(struct kvm_signal_mask, sigset)
+ sizeof(sigset_t));
sigset_t *sigset = (sigset_t *) &sigmask->sigset;
/*
* SIG_IPI is unblocked atomically while in KVM_RUN. It causes the
* ioctl to return with -EINTR, but it is still pending and we need
* to accept it with the sigwait.
*/
sigmask->len = 8;
pthread_sigmask(0, NULL, sigset);
sigdelset(sigset, SIG_IPI);
vcpu_ioctl(vcpu, KVM_SET_SIGNAL_MASK, sigmask);
sigemptyset(sigset);
sigaddset(sigset, SIG_IPI);
guest_array = addr_gva2hva(vm, (vm_vaddr_t)random_array);
while (!READ_ONCE(host_quit)) {
/* Clear any existing kick signals */
generate_random_array(guest_array, TEST_PAGES_PER_LOOP);
pages_count += TEST_PAGES_PER_LOOP;
/* Let the guest dirty the random pages */
ret = __vcpu_run(vcpu);
if (ret == -1 && errno == EINTR) {
int sig = -1;
sigwait(sigset, &sig);
assert(sig == SIG_IPI);
}
log_mode_after_vcpu_run(vcpu, ret, errno);
}
pr_info("Dirtied %"PRIu64" pages\n", pages_count);
return NULL;
}
static void vm_dirty_log_verify(enum vm_guest_mode mode, unsigned long *bmap)
{
uint64_t step = vm_num_host_pages(mode, 1);
uint64_t page;
uint64_t *value_ptr;
uint64_t min_iter = 0;
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_le(page, host_bmap_track)) {
host_track_next_count++;
TEST_ASSERT(test_bit_le(page, bmap),
"Page %"PRIu64" should have its dirty bit "
"set in this iteration but it is missing",
page);
}
if (__test_and_clear_bit_le(page, bmap)) {
bool matched;
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.
*/
matched = (*value_ptr == iteration ||
*value_ptr == iteration - 1);
if (host_log_mode == LOG_MODE_DIRTY_RING && !matched) {
if (*value_ptr == iteration - 2 && min_iter <= iteration - 2) {
/*
* Short answer: this case is special
* only for dirty ring test where the
* page is the last page before a kvm
* dirty ring full in iteration N-2.
*
* Long answer: Assuming ring size R,
* one possible condition is:
*
* main thr vcpu thr
* -------- --------
* iter=1
* write 1 to page 0~(R-1)
* full, vmexit
* collect 0~(R-1)
* kick vcpu
* write 1 to (R-1)~(2R-2)
* full, vmexit
* iter=2
* collect (R-1)~(2R-2)
* kick vcpu
* write 1 to (2R-2)
* (NOTE!!! "1" cached in cpu reg)
* write 2 to (2R-1)~(3R-3)
* full, vmexit
* iter=3
* collect (2R-2)~(3R-3)
* (here if we read value on page
* "2R-2" is 1, while iter=3!!!)
*
* This however can only happen once per iteration.
*/
min_iter = iteration - 1;
continue;
} else if (page == dirty_ring_last_page) {
/*
* Please refer to comments in
* dirty_ring_last_page.
*/
continue;
}
}
TEST_ASSERT(matched,
"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_le(page, host_bmap_track);
}
}
}
}
static struct kvm_vm *create_vm(enum vm_guest_mode mode, struct kvm_vcpu **vcpu,
uint64_t extra_mem_pages, void *guest_code)
{
struct kvm_vm *vm;
pr_info("Testing guest mode: %s\n", vm_guest_mode_string(mode));
vm = __vm_create(mode, 1, extra_mem_pages);
log_mode_create_vm_done(vm);
*vcpu = vm_vcpu_add(vm, 0, guest_code);
return vm;
}
#define DIRTY_MEM_BITS 30 /* 1G */
#define PAGE_SHIFT_4K 12
struct test_params {
unsigned long iterations;
unsigned long interval;
uint64_t phys_offset;
};
static void run_test(enum vm_guest_mode mode, void *arg)
{
struct test_params *p = arg;
struct kvm_vcpu *vcpu;
struct kvm_vm *vm;
unsigned long *bmap;
if (!log_mode_supported()) {
print_skip("Log mode '%s' not supported",
log_modes[host_log_mode].name);
return;
}
/*
* We reserve page table for 2 times of extra dirty mem which
* will definitely cover the original (1G+) test range. Here
* we do the calculation with 4K page size which is the
* smallest so the page number will be enough for all archs
* (e.g., 64K page size guest will need even less memory for
* page tables).
*/
vm = create_vm(mode, &vcpu,
2ul << (DIRTY_MEM_BITS - PAGE_SHIFT_4K), guest_code);
guest_page_size = vm->page_size;
/*
* A little more than 1G of guest page sized pages. Cover the
* case where the size is not aligned to 64 pages.
*/
guest_num_pages = (1ul << (DIRTY_MEM_BITS - vm->page_shift)) + 3;
guest_num_pages = vm_adjust_num_guest_pages(mode, guest_num_pages);
host_page_size = getpagesize();
host_num_pages = vm_num_host_pages(mode, guest_num_pages);
if (!p->phys_offset) {
guest_test_phys_mem = (vm->max_gfn - guest_num_pages) *
guest_page_size;
guest_test_phys_mem = align_down(guest_test_phys_mem, host_page_size);
} else {
guest_test_phys_mem = p->phys_offset;
}
#ifdef __s390x__
/* Align to 1M (segment size) */
guest_test_phys_mem = align_down(guest_test_phys_mem, 1 << 20);
#endif
pr_info("guest physical test memory offset: 0x%lx\n", guest_test_phys_mem);
bmap = bitmap_zalloc(host_num_pages);
host_bmap_track = bitmap_zalloc(host_num_pages);
/* Add an extra memory slot for testing dirty logging */
vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS,
guest_test_phys_mem,
TEST_MEM_SLOT_INDEX,
guest_num_pages,
KVM_MEM_LOG_DIRTY_PAGES);
/* Do mapping for the dirty track memory slot */
virt_map(vm, guest_test_virt_mem, guest_test_phys_mem, guest_num_pages);
/* Cache the HVA pointer of the region */
host_test_mem = addr_gpa2hva(vm, (vm_paddr_t)guest_test_phys_mem);
/* 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_virt_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, vcpu);
while (iteration < p->iterations) {
/* Give the vcpu thread some time to dirty some pages */
usleep(p->interval * 1000);
log_mode_collect_dirty_pages(vcpu, TEST_MEM_SLOT_INDEX,
bmap, host_num_pages);
/*
* See vcpu_sync_stop_requested definition for details on why
* we need to stop vcpu when verify data.
*/
atomic_set(&vcpu_sync_stop_requested, true);
sem_wait_until(&sem_vcpu_stop);
/*
* NOTE: for dirty ring, it's possible that we didn't stop at
* GUEST_SYNC but instead we stopped because ring is full;
* that's okay too because ring full means we're only missing
* the flush of the last page, and since we handle the last
* page specially verification will succeed anyway.
*/
assert(host_log_mode == LOG_MODE_DIRTY_RING ||
atomic_read(&vcpu_sync_stop_requested) == false);
vm_dirty_log_verify(mode, bmap);
sem_post(&sem_vcpu_cont);
iteration++;
sync_global_to_guest(vm, iteration);
}
/* Tell the vcpu thread to quit */
host_quit = true;
log_mode_before_vcpu_join();
pthread_join(vcpu_thread, NULL);
pr_info("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);
kvm_vm_free(vm);
}
static void help(char *name)
{
puts("");
printf("usage: %s [-h] [-i iterations] [-I interval] "
"[-p offset] [-m mode]\n", name);
puts("");
printf(" -c: specify dirty ring size, in number of entries\n");
printf(" (only useful for dirty-ring test; default: %"PRIu32")\n",
TEST_DIRTY_RING_COUNT);
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(" -p: specify guest physical test memory offset\n"
" Warning: a low offset can conflict with the loaded test code.\n");
printf(" -M: specify the host logging mode "
"(default: run all log modes). Supported modes: \n\t");
log_modes_dump();
guest_modes_help();
puts("");
exit(0);
}
int main(int argc, char *argv[])
{
struct test_params p = {
.iterations = TEST_HOST_LOOP_N,
.interval = TEST_HOST_LOOP_INTERVAL,
};
int opt, i;
sigset_t sigset;
sem_init(&sem_vcpu_stop, 0, 0);
sem_init(&sem_vcpu_cont, 0, 0);
guest_modes_append_default();
while ((opt = getopt(argc, argv, "c:hi:I:p:m:M:")) != -1) {
switch (opt) {
case 'c':
test_dirty_ring_count = strtol(optarg, NULL, 10);
break;
case 'i':
p.iterations = strtol(optarg, NULL, 10);
break;
case 'I':
p.interval = strtol(optarg, NULL, 10);
break;
case 'p':
p.phys_offset = strtoull(optarg, NULL, 0);
break;
case 'm':
guest_modes_cmdline(optarg);
break;
case 'M':
if (!strcmp(optarg, "all")) {
host_log_mode_option = LOG_MODE_ALL;
break;
}
for (i = 0; i < LOG_MODE_NUM; i++) {
if (!strcmp(optarg, log_modes[i].name)) {
pr_info("Setting log mode to: '%s'\n",
optarg);
host_log_mode_option = i;
break;
}
}
if (i == LOG_MODE_NUM) {
printf("Log mode '%s' invalid. Please choose "
"from: ", optarg);
log_modes_dump();
exit(1);
}
break;
case 'h':
default:
help(argv[0]);
break;
}
}
TEST_ASSERT(p.iterations > 2, "Iterations must be greater than two");
TEST_ASSERT(p.interval > 0, "Interval must be greater than zero");
pr_info("Test iterations: %"PRIu64", interval: %"PRIu64" (ms)\n",
p.iterations, p.interval);
srandom(time(0));
/* Ensure that vCPU threads start with SIG_IPI blocked. */
sigemptyset(&sigset);
sigaddset(&sigset, SIG_IPI);
pthread_sigmask(SIG_BLOCK, &sigset, NULL);
if (host_log_mode_option == LOG_MODE_ALL) {
/* Run each log mode */
for (i = 0; i < LOG_MODE_NUM; i++) {
pr_info("Testing Log Mode '%s'\n", log_modes[i].name);
host_log_mode = i;
for_each_guest_mode(run_test, &p);
}
} else {
host_log_mode = host_log_mode_option;
for_each_guest_mode(run_test, &p);
}
return 0;
}
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