rdma: allow state transitions between other states besides ACTIVE

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.

Reviewed-by: Juan Quintela <quintela@redhat.com>
Tested-by: Michael R. Hines <mrhines@us.ibm.com>
Signed-off-by: Michael R. Hines <mrhines@us.ibm.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
master
Michael R. Hines 2013-07-22 10:01:56 -04:00 committed by Juan Quintela
parent 0033b8b42a
commit d58f574bf3
1 changed files with 6 additions and 6 deletions

View File

@ -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 (atomic_cmpxchg(&s->state, MIG_STATE_ACTIVE, new_state) == new_state) {
if (atomic_cmpxchg(&s->state, old_state, new_state) == new_state) {
trace_migrate_set_state(new_state);
}
}
@ -315,7 +315,7 @@ static void migrate_fd_cancel(MigrationState *s)
{
DPRINTF("cancelling migration\n");
migrate_finish_set_state(s, MIG_STATE_CANCELLED);
migrate_set_state(s, s->state, MIG_STATE_CANCELLED);
}
void add_migration_state_change_notifier(Notifier *notify)
@ -569,19 +569,19 @@ static void *migration_thread(void *opaque)
qemu_mutex_unlock_iothread();
if (ret < 0) {
migrate_finish_set_state(s, MIG_STATE_ERROR);
migrate_set_state(s, MIG_STATE_ACTIVE, MIG_STATE_ERROR);
break;
}
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);