Message ID | 1372125485-11795-14-git-send-email-mrhines@linux.vnet.ibm.com |
---|---|
State | New |
Headers | show |
mrhines@linux.vnet.ibm.com wrote: > From: "Michael R. Hines" <mrhines@us.ibm.com> > > This patch is in preparation for the next ones: Until now the MIG_STATE_SETUP > state was not really a 'formal' state. It has been used as a 'zero' state > and QEMU has been unconditionally transitioning into this state when > the QMP migrate command was called. In preparation for timing this state, > we have to make this state a a 'real' state which actually gets transitioned > from later in the migration_thread() from SETUP => ACTIVE, rather than just > automatically dropping into this state at the beginninig of the migration. > > This means that the state transition function (migration_finish_set_state()) > needs to be capable of transitioning from valid states _other_ than just > MIG_STATE_ACTIVE. > > The function is in fact already capable of doing that, but was not allowing the > old state to be a parameter specified as an input. > > This patch fixes that and only makes the transition if the current state > matches the old state that the caller intended to transition from. > > Tested-by: Michael R. Hines <mrhines@us.ibm.com> > Signed-off-by: Michael R. Hines <mrhines@us.ibm.com> Reviewed-by: Juan Quintela <quintela@redhat.com>
diff --git a/migration.c b/migration.c index 62c6b85..dcb99c9 100644 --- a/migration.c +++ b/migration.c @@ -295,9 +295,9 @@ static void migrate_fd_cleanup(void *opaque) notifier_list_notify(&migration_state_notifiers, s); } -static void migrate_finish_set_state(MigrationState *s, int new_state) +static void migrate_set_state(MigrationState *s, int old_state, int new_state) { - if (__sync_val_compare_and_swap(&s->state, MIG_STATE_ACTIVE, + if (__sync_val_compare_and_swap(&s->state, old_state, new_state) == new_state) { trace_migrate_set_state(new_state); } @@ -316,7 +316,7 @@ static void migrate_fd_cancel(MigrationState *s) { DPRINTF("cancelling migration\n"); - migrate_finish_set_state(s, MIG_STATE_CANCELLED); + migrate_set_state(s, MIG_STATE_ACTIVE, MIG_STATE_CANCELLED); } void add_migration_state_change_notifier(Notifier *notify) @@ -546,14 +546,14 @@ static void *migration_thread(void *opaque) 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); + migrate_set_state(s, MIG_STATE_ACTIVE, MIG_STATE_COMPLETED); break; } } } if (qemu_file_get_error(s->file)) { - migrate_finish_set_state(s, MIG_STATE_ERROR); + migrate_set_state(s, MIG_STATE_ACTIVE, MIG_STATE_ERROR); break; } current_time = qemu_get_clock_ms(rt_clock);