Peter Xu <peterx@redhat.com> wrote:
> It converts the old if clauses into switch, explicitly mentions the
> possible migration states. The old nested "if"s are not clear on what
> we do on different states.
>
> Signed-off-by: Peter Xu <peterx@redhat.com>
> ---
> migration/migration.c | 32 +++++++++++++++++++++-----------
> 1 file changed, 21 insertions(+), 11 deletions(-)
>
> diff --git a/migration/migration.c b/migration/migration.c
> index acef54748b..bfcba24caa 100644
> --- a/migration/migration.c
> +++ b/migration/migration.c
> @@ -2296,19 +2296,23 @@ static void *migration_thread(void *opaque)
> cpu_throttle_stop();
>
> qemu_mutex_lock_iothread();
> - if (s->state == MIGRATION_STATUS_COMPLETED) {
> + switch (s->state) {
> + case MIGRATION_STATUS_COMPLETED:
> migration_calculate_complete(s);
> runstate_set(RUN_STATE_POSTMIGRATE);
> - } else {
> - if (s->state == MIGRATION_STATUS_ACTIVE) {
> - assert(migrate_colo_enabled());
> - migrate_start_colo_process(s);
> - /*
> - * Fixme: we will run VM in COLO no matter its old running state.
> - * After exited COLO, we will keep running.
> - */
> - s->old_vm_running = true;
> - }
> + break;
> +
> + case MIGRATION_STATUS_ACTIVE:
> + assert(migrate_colo_enabled());
> + migrate_start_colo_process(s);
I think this line is wrong, you still have to proctect it with the if
(migrate_cole_enabled).
Rest of cleanup, is something that I like.
Later, Juan.
> + /*
> + * Fixme: we will run VM in COLO no matter its old running state.
> + * After exited COLO, we will keep running.
> + */
> + s->old_vm_running = true;
> + /* Fallthrough */
Actually, I don't like Fallthrought on C, but well, problem is C O:-)
> + case MIGRATION_STATUS_FAILED:
> + case MIGRATION_STATUS_CANCELLED:
> if (s->old_vm_running) {
> vm_start();
> } else {
> @@ -2316,6 +2320,12 @@ static void *migration_thread(void *opaque)
> runstate_set(RUN_STATE_POSTMIGRATE);
> }
> }
> + break;
> +
> + default:
> + /* Should not reach here, but if so, forgive the VM. */
> + error_report("%s: Unknown ending state %d", __func__, s->state);
> + break;
> }
> qemu_bh_schedule(s->cleanup_bh);
> qemu_mutex_unlock_iothread();