#include "migration/block.h"
#include "qemu/thread.h"
#include "qmp-commands.h"
+#include "trace.h"
//#define DEBUG_MIGRATION
fd_start_incoming_migration(p, errp);
#endif
else {
- error_setg(errp, "unknown migration protocol: %s\n", uri);
+ error_setg(errp, "unknown migration protocol: %s", uri);
}
}
int ret;
ret = qemu_loadvm_state(f);
- qemu_set_fd_handler(qemu_get_fd(f), NULL, NULL, NULL);
qemu_fclose(f);
if (ret < 0) {
fprintf(stderr, "load of migration failed\n");
}
}
-static void enter_migration_coroutine(void *opaque)
-{
- Coroutine *co = opaque;
- qemu_coroutine_enter(co, NULL);
-}
-
void process_incoming_migration(QEMUFile *f)
{
Coroutine *co = qemu_coroutine_create(process_incoming_migration_co);
assert(fd != -1);
socket_set_nonblock(fd);
- qemu_set_fd_handler(fd, enter_migration_coroutine, NULL, co);
qemu_coroutine_enter(co, f);
}
/* shared migration helpers */
-static int migrate_fd_cleanup(MigrationState *s)
+static void migrate_fd_cleanup(void *opaque)
{
- int ret = 0;
+ MigrationState *s = opaque;
+
+ qemu_bh_delete(s->cleanup_bh);
+ s->cleanup_bh = NULL;
if (s->file) {
DPRINTF("closing file\n");
- ret = qemu_fclose(s->file);
+ qemu_mutex_unlock_iothread();
+ qemu_thread_join(&s->thread);
+ qemu_mutex_lock_iothread();
+
+ qemu_fclose(s->file);
s->file = NULL;
}
- assert(s->fd == -1);
- return ret;
-}
+ assert(s->state != MIG_STATE_ACTIVE);
+
+ if (s->state != MIG_STATE_COMPLETED) {
+ qemu_savevm_state_cancel();
+ }
-void migrate_fd_error(MigrationState *s)
-{
- DPRINTF("setting error state\n");
- s->state = MIG_STATE_ERROR;
notifier_list_notify(&migration_state_notifiers, s);
- migrate_fd_cleanup(s);
}
-static void migrate_fd_completed(MigrationState *s)
+static void migrate_finish_set_state(MigrationState *s, int new_state)
{
- DPRINTF("setting completed state\n");
- if (migrate_fd_cleanup(s) < 0) {
- s->state = MIG_STATE_ERROR;
- } else {
- s->state = MIG_STATE_COMPLETED;
- runstate_set(RUN_STATE_POSTMIGRATE);
+ if (__sync_val_compare_and_swap(&s->state, MIG_STATE_ACTIVE,
+ new_state) == new_state) {
+ trace_migrate_set_state(new_state);
}
- notifier_list_notify(&migration_state_notifiers, s);
}
-ssize_t migrate_fd_put_buffer(MigrationState *s, const void *data,
- size_t size)
+void migrate_fd_error(MigrationState *s)
{
- ssize_t ret;
-
- if (s->state != MIG_STATE_ACTIVE) {
- return -EIO;
- }
-
- do {
- ret = s->write(s, data, size);
- } while (ret == -1 && ((s->get_error(s)) == EINTR));
-
- if (ret == -1)
- ret = -(s->get_error(s));
-
- return ret;
+ DPRINTF("setting error state\n");
+ assert(s->file == NULL);
+ s->state = MIG_STATE_ERROR;
+ trace_migrate_set_state(MIG_STATE_ERROR);
+ notifier_list_notify(&migration_state_notifiers, s);
}
static void migrate_fd_cancel(MigrationState *s)
{
- if (s->state != MIG_STATE_ACTIVE)
- return;
-
DPRINTF("cancelling migration\n");
- s->state = MIG_STATE_CANCELLED;
- notifier_list_notify(&migration_state_notifiers, s);
- qemu_savevm_state_cancel(s->file);
-
- migrate_fd_cleanup(s);
-}
-
-int migrate_fd_close(MigrationState *s)
-{
- int rc = 0;
- if (s->fd != -1) {
- rc = s->close(s);
- s->fd = -1;
- }
- return rc;
+ migrate_finish_set_state(s, MIG_STATE_CANCELLED);
}
void add_migration_state_change_notifier(Notifier *notify)
s->bandwidth_limit = bandwidth_limit;
s->state = MIG_STATE_SETUP;
- s->total_time = qemu_get_clock_ms(rt_clock);
+ trace_migrate_set_state(MIG_STATE_SETUP);
+ s->total_time = qemu_get_clock_ms(rt_clock);
return s;
}
if (value < 0) {
value = 0;
}
+ if (value > SIZE_MAX) {
+ value = SIZE_MAX;
+ }
s = migrate_get_current();
s->bandwidth_limit = value;
- qemu_file_set_rate_limit(s->file, s->bandwidth_limit);
+ if (s->file) {
+ qemu_file_set_rate_limit(s->file, s->bandwidth_limit / XFER_LIMIT_RATIO);
+ }
}
void qmp_migrate_set_downtime(double value, Error **errp)
/* migration thread support */
-
-static ssize_t buffered_flush(MigrationState *s)
-{
- size_t offset = 0;
- ssize_t ret = 0;
-
- DPRINTF("flushing %zu byte(s) of data\n", s->buffer_size);
-
- while (s->bytes_xfer < s->xfer_limit && offset < s->buffer_size) {
- size_t to_send = MIN(s->buffer_size - offset, s->xfer_limit - s->bytes_xfer);
- ret = migrate_fd_put_buffer(s, s->buffer + offset, to_send);
- if (ret <= 0) {
- DPRINTF("error flushing data, %zd\n", ret);
- break;
- } else {
- DPRINTF("flushed %zd byte(s)\n", ret);
- offset += ret;
- s->bytes_xfer += ret;
- }
- }
-
- DPRINTF("flushed %zu of %zu byte(s)\n", offset, s->buffer_size);
- memmove(s->buffer, s->buffer + offset, s->buffer_size - offset);
- s->buffer_size -= offset;
-
- if (ret < 0) {
- return ret;
- }
- return offset;
-}
-
-static int buffered_put_buffer(void *opaque, const uint8_t *buf,
- int64_t pos, int size)
-{
- MigrationState *s = opaque;
- ssize_t error;
-
- DPRINTF("putting %d bytes at %" PRId64 "\n", size, pos);
-
- error = qemu_file_get_error(s->file);
- if (error) {
- DPRINTF("flush when error, bailing: %s\n", strerror(-error));
- return error;
- }
-
- if (size <= 0) {
- return size;
- }
-
- if (size > (s->buffer_capacity - s->buffer_size)) {
- DPRINTF("increasing buffer capacity from %zu by %zu\n",
- s->buffer_capacity, size + 1024);
-
- s->buffer_capacity += size + 1024;
-
- s->buffer = g_realloc(s->buffer, s->buffer_capacity);
- }
-
- memcpy(s->buffer + s->buffer_size, buf, size);
- s->buffer_size += size;
-
- return size;
-}
-
-static int buffered_close(void *opaque)
-{
- MigrationState *s = opaque;
- ssize_t ret = 0;
- int ret2;
-
- DPRINTF("closing\n");
-
- s->xfer_limit = INT_MAX;
- while (!qemu_file_get_error(s->file) && s->buffer_size) {
- ret = buffered_flush(s);
- if (ret < 0) {
- break;
- }
- }
-
- ret2 = migrate_fd_close(s);
- if (ret >= 0) {
- ret = ret2;
- }
- ret = migrate_fd_close(s);
- s->complete = true;
- return ret;
-}
-
-static int buffered_get_fd(void *opaque)
-{
- MigrationState *s = opaque;
-
- return s->fd;
-}
-
-/*
- * The meaning of the return values is:
- * 0: We can continue sending
- * 1: Time to stop
- * negative: There has been an error
- */
-static int buffered_rate_limit(void *opaque)
-{
- MigrationState *s = opaque;
- int ret;
-
- ret = qemu_file_get_error(s->file);
- if (ret) {
- return ret;
- }
-
- if (s->bytes_xfer > s->xfer_limit) {
- return 1;
- }
-
- return 0;
-}
-
-static int64_t buffered_set_rate_limit(void *opaque, int64_t new_rate)
-{
- MigrationState *s = opaque;
- if (qemu_file_get_error(s->file)) {
- goto out;
- }
- if (new_rate > SIZE_MAX) {
- new_rate = SIZE_MAX;
- }
-
- s->xfer_limit = new_rate / 10;
-
-out:
- return s->xfer_limit;
-}
-
-static int64_t buffered_get_rate_limit(void *opaque)
-{
- MigrationState *s = opaque;
-
- return s->xfer_limit;
-}
-
-static bool migrate_fd_put_ready(MigrationState *s, uint64_t max_size)
-{
- int ret;
- uint64_t pending_size;
- bool last_round = false;
-
- qemu_mutex_lock_iothread();
- if (s->state != MIG_STATE_ACTIVE) {
- DPRINTF("put_ready returning because of non-active state\n");
- qemu_mutex_unlock_iothread();
- return false;
- }
- if (s->first_time) {
- s->first_time = false;
- DPRINTF("beginning savevm\n");
- ret = qemu_savevm_state_begin(s->file, &s->params);
- if (ret < 0) {
- DPRINTF("failed, %d\n", ret);
- migrate_fd_error(s);
- qemu_mutex_unlock_iothread();
- return false;
- }
- }
-
- DPRINTF("iterate\n");
- pending_size = qemu_savevm_state_pending(s->file, max_size);
- DPRINTF("pending size %lu max %lu\n", pending_size, max_size);
- if (pending_size >= max_size) {
- ret = qemu_savevm_state_iterate(s->file);
- if (ret < 0) {
- migrate_fd_error(s);
- }
- } else {
- int old_vm_running = runstate_is_running();
- int64_t start_time, end_time;
-
- DPRINTF("done iterating\n");
- start_time = qemu_get_clock_ms(rt_clock);
- qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER);
- if (old_vm_running) {
- vm_stop(RUN_STATE_FINISH_MIGRATE);
- } else {
- vm_stop_force_state(RUN_STATE_FINISH_MIGRATE);
- }
-
- if (qemu_savevm_state_complete(s->file) < 0) {
- migrate_fd_error(s);
- } else {
- migrate_fd_completed(s);
- }
- end_time = qemu_get_clock_ms(rt_clock);
- s->total_time = end_time - s->total_time;
- s->downtime = end_time - start_time;
- if (s->state != MIG_STATE_COMPLETED) {
- if (old_vm_running) {
- vm_start();
- }
- }
- last_round = true;
- }
- qemu_mutex_unlock_iothread();
-
- return last_round;
-}
-
-static void *buffered_file_thread(void *opaque)
+static void *migration_thread(void *opaque)
{
MigrationState *s = opaque;
int64_t initial_time = qemu_get_clock_ms(rt_clock);
+ int64_t sleep_time = 0;
+ int64_t initial_bytes = 0;
int64_t max_size = 0;
- bool last_round = false;
-
- while (true) {
- int64_t current_time = qemu_get_clock_ms(rt_clock);
+ int64_t start_time = initial_time;
+ bool old_vm_running = false;
+
+ DPRINTF("beginning savevm\n");
+ qemu_savevm_state_begin(s->file, &s->params);
+
+ while (s->state == MIG_STATE_ACTIVE) {
+ int64_t current_time;
+ uint64_t pending_size;
+
+ if (!qemu_file_rate_limit(s->file)) {
+ DPRINTF("iterate\n");
+ pending_size = qemu_savevm_state_pending(s->file, max_size);
+ DPRINTF("pending size %lu max %lu\n", pending_size, max_size);
+ if (pending_size && pending_size >= max_size) {
+ qemu_savevm_state_iterate(s->file);
+ } else {
+ DPRINTF("done iterating\n");
+ qemu_mutex_lock_iothread();
+ start_time = qemu_get_clock_ms(rt_clock);
+ qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER);
+ old_vm_running = runstate_is_running();
+ vm_stop_force_state(RUN_STATE_FINISH_MIGRATE);
+ qemu_file_set_rate_limit(s->file, INT_MAX);
+ qemu_savevm_state_complete(s->file);
+ qemu_mutex_unlock_iothread();
+ if (!qemu_file_get_error(s->file)) {
+ migrate_finish_set_state(s, MIG_STATE_COMPLETED);
+ break;
+ }
+ }
+ }
- if (s->complete) {
+ if (qemu_file_get_error(s->file)) {
+ migrate_finish_set_state(s, MIG_STATE_ERROR);
break;
}
+ current_time = qemu_get_clock_ms(rt_clock);
if (current_time >= initial_time + BUFFER_DELAY) {
- uint64_t transferred_bytes = s->bytes_xfer;
- uint64_t time_spent = current_time - initial_time;
+ uint64_t transferred_bytes = qemu_ftell(s->file) - initial_bytes;
+ uint64_t time_spent = current_time - initial_time - sleep_time;
double bandwidth = transferred_bytes / time_spent;
max_size = bandwidth * migrate_max_downtime() / 1000000;
DPRINTF("transferred %" PRIu64 " time_spent %" PRIu64
" bandwidth %g max_size %" PRId64 "\n",
transferred_bytes, time_spent, bandwidth, max_size);
+ /* if we haven't sent anything, we don't want to recalculate
+ 10000 is a small enough number for our purposes */
+ if (s->dirty_bytes_rate && transferred_bytes > 10000) {
+ s->expected_downtime = s->dirty_bytes_rate / bandwidth;
+ }
- s->bytes_xfer = 0;
+ qemu_file_reset_rate_limit(s->file);
+ sleep_time = 0;
initial_time = current_time;
+ initial_bytes = qemu_ftell(s->file);
}
- if (!last_round && (s->bytes_xfer >= s->xfer_limit)) {
+ if (qemu_file_rate_limit(s->file)) {
/* usleep expects microseconds */
g_usleep((initial_time + BUFFER_DELAY - current_time)*1000);
+ sleep_time += qemu_get_clock_ms(rt_clock) - current_time;
}
- if (buffered_flush(s) < 0) {
- break;
- }
+ }
- DPRINTF("file is ready\n");
- if (s->bytes_xfer < s->xfer_limit) {
- DPRINTF("notifying client\n");
- last_round = migrate_fd_put_ready(s, max_size);
+ qemu_mutex_lock_iothread();
+ if (s->state == MIG_STATE_COMPLETED) {
+ int64_t end_time = qemu_get_clock_ms(rt_clock);
+ s->total_time = end_time - s->total_time;
+ s->downtime = end_time - start_time;
+ runstate_set(RUN_STATE_POSTMIGRATE);
+ } else {
+ if (old_vm_running) {
+ vm_start();
}
}
+ qemu_bh_schedule(s->cleanup_bh);
+ qemu_mutex_unlock_iothread();
- g_free(s->buffer);
return NULL;
}
-static const QEMUFileOps buffered_file_ops = {
- .get_fd = buffered_get_fd,
- .put_buffer = buffered_put_buffer,
- .close = buffered_close,
- .rate_limit = buffered_rate_limit,
- .get_rate_limit = buffered_get_rate_limit,
- .set_rate_limit = buffered_set_rate_limit,
-};
-
void migrate_fd_connect(MigrationState *s)
{
s->state = MIG_STATE_ACTIVE;
- s->bytes_xfer = 0;
- s->buffer = NULL;
- s->buffer_size = 0;
- s->buffer_capacity = 0;
-
- s->first_time = true;
+ trace_migrate_set_state(MIG_STATE_ACTIVE);
- s->xfer_limit = s->bandwidth_limit / XFER_LIMIT_RATIO;
- s->complete = false;
+ /* This is a best 1st approximation. ns to ms */
+ s->expected_downtime = max_downtime/1000000;
+ s->cleanup_bh = qemu_bh_new(migrate_fd_cleanup, s);
- s->file = qemu_fopen_ops(s, &buffered_file_ops);
+ qemu_file_set_rate_limit(s->file,
+ s->bandwidth_limit / XFER_LIMIT_RATIO);
- qemu_thread_create(&s->thread, buffered_file_thread, s,
- QEMU_THREAD_DETACHED);
+ qemu_thread_create(&s->thread, migration_thread, s,
+ QEMU_THREAD_JOINABLE);
notifier_list_notify(&migration_state_notifiers, s);
}