migration/qmp: add command migrate-pause

It pauses an ongoing migration.  Currently it only supports postcopy.
Note that this command will work on either side of the migration.
Basically when we trigger this on one side, it'll interrupt the other
side as well since the other side will get notified on the disconnect
event.

However, it's still possible that the other side is not notified, for
example, when the network is totally broken, or due to some firewall
configuration changes.  In that case, we will also need to run the same
command on the other side so both sides will go into the paused state.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180502104740.12123-24-peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>

---
s/2.12/2.13/
This commit is contained in:
Peter Xu 2018-05-02 18:47:39 +08:00 committed by Juan Quintela
parent 62df066fff
commit bfbf89c2b5
2 changed files with 45 additions and 0 deletions

View File

@ -1507,6 +1507,35 @@ void qmp_migrate_recover(const char *uri, Error **errp)
qemu_start_incoming_migration(uri, errp);
}
void qmp_migrate_pause(Error **errp)
{
MigrationState *ms = migrate_get_current();
MigrationIncomingState *mis = migration_incoming_get_current();
int ret;
if (ms->state == MIGRATION_STATUS_POSTCOPY_ACTIVE) {
/* Source side, during postcopy */
qemu_mutex_lock(&ms->qemu_file_lock);
ret = qemu_file_shutdown(ms->to_dst_file);
qemu_mutex_unlock(&ms->qemu_file_lock);
if (ret) {
error_setg(errp, "Failed to pause source migration");
}
return;
}
if (mis->state == MIGRATION_STATUS_POSTCOPY_ACTIVE) {
ret = qemu_file_shutdown(mis->from_src_file);
if (ret) {
error_setg(errp, "Failed to pause destination migration");
}
return;
}
error_setg(errp, "migrate-pause is currently only supported "
"during postcopy-active state");
}
bool migration_is_blocked(Error **errp)
{
if (qemu_savevm_state_blocked(errp)) {

View File

@ -1211,3 +1211,19 @@
##
{ 'command': 'migrate-recover', 'data': { 'uri': 'str' },
'allow-oob': true }
##
# @migrate-pause:
#
# Pause a migration. Currently it only supports postcopy.
#
# Returns: nothing.
#
# Example:
#
# -> { "execute": "migrate-pause" }
# <- { "return": {} }
#
# Since: 2.13
##
{ 'command': 'migrate-pause', 'allow-oob': true }