On 02/15/2013 07:46 PM, Paolo Bonzini wrote:
> Completion of migration is currently done with a "nested" loop that
> invokes buffered_flush: migrate_fd_completed is called by
> buffered_file_thread, which calls migrate_fd_cleanup, which calls
> buffered_close (via qemu_fclose), which flushes the buffer.
>
> Simplify this, by reusing the buffered_flush call of buffered_file_thread.
> Then if qemu_savevm_state_complete was called, and the buffer is empty
> (including the QEMUFile buffer, for which we need the previous patch), we
> are done.
>
> Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
> ---
> migration.c | 55 ++++++++++++++++++++++++-------------------------------
> 1 files changed, 24 insertions(+), 31 deletions(-)
>
> diff --git a/migration.c b/migration.c
> index 75dd38a..b0b5578 100644
> --- a/migration.c
> +++ b/migration.c
> @@ -262,41 +262,34 @@ void
> qmp_migrate_set_capabilities(MigrationCapabilityStatusList *params,
>
> static void migrate_fd_cleanup(MigrationState *s)
> {
> - int ret = 0;
> -
> if (s->file) {
> DPRINTF("closing file\n");
> - ret = qemu_fclose(s->file);
> + qemu_fclose(s->file);
> s->file = NULL;
> }
>
> assert(s->fd == -1);
> - if (ret < 0 && s->state == MIG_STATE_ACTIVE) {
> - s->state = MIG_STATE_ERROR;
> - }
> + assert(s->state != MIG_STATE_ACTIVE);
>
> - if (s->state != MIG_STATE_ACTIVE) {
> + if (s->state != MIG_STATE_COMPLETED) {
> qemu_savevm_state_cancel();
> }
> +
> + notifier_list_notify(&migration_state_notifiers, s);
> }
>
> 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)
> {
> DPRINTF("setting completed state\n");
> + s->state = MIG_STATE_COMPLETED;
> migrate_fd_cleanup(s);
> - if (s->state == MIG_STATE_ACTIVE) {
> - s->state = MIG_STATE_COMPLETED;
> - runstate_set(RUN_STATE_POSTMIGRATE);
> - }
> - notifier_list_notify(&migration_state_notifiers, s);
> }
>
> static ssize_t migrate_fd_put_buffer(MigrationState *s, const void *data,
> @@ -326,8 +319,6 @@ static void migrate_fd_cancel(MigrationState *s)
> DPRINTF("cancelling migration\n");
>
> s->state = MIG_STATE_CANCELLED;
> - notifier_list_notify(&migration_state_notifiers, s);
> -
> migrate_fd_cleanup(s);
> }
>
> @@ -592,10 +583,6 @@ static int buffered_close(void *opaque)
>
> DPRINTF("closing\n");
>
> - s->xfer_limit = INT_MAX;
> - while (!qemu_file_get_error(s->file) && s->buffer_size) {
> - buffered_flush(s);
> - }
> return migrate_fd_close(s);
> }
>
> @@ -657,6 +644,8 @@ static void *buffered_file_thread(void *opaque)
> MigrationState *s = opaque;
> int64_t initial_time = qemu_get_clock_ms(rt_clock);
> int64_t max_size = 0;
> + int64_t start_time = initial_time;
> + bool old_vm_running = false;
> bool last_round = false;
>
> qemu_mutex_lock_iothread();
> @@ -674,23 +663,13 @@ static void *buffered_file_thread(void *opaque)
> if (pending_size && pending_size >= max_size) {
> qemu_savevm_state_iterate(s->file);
> } 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);
> + old_vm_running = runstate_is_running();
> vm_stop_force_state(RUN_STATE_FINISH_MIGRATE);
> + s->xfer_limit = INT_MAX;
> qemu_savevm_state_complete(s->file);
> - 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;
> }
> }
> @@ -716,6 +695,20 @@ static void *buffered_file_thread(void *opaque)
> qemu_mutex_lock_iothread();
> if (qemu_file_get_error(s->file)) {
> migrate_fd_error(s);
> + } else if (last_round && s->buffer_size == 0) {
> + migrate_fd_completed(s);
> + }
> + }
> +
> + 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) {
> + assert(last_round);
> + vm_start();
> }
> }
>
>
Reviewed-by: Orit Wasserman <owass...@redhat.com>
