* Peter Xu (peterx@redhat.com) wrote:
> 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.
>
> Signed-off-by: Peter Xu <peterx@redhat.com>
> ---
> migration/migration.c | 27 +++++++++++++++++++++++++++
> qapi/migration.json | 16 ++++++++++++++++
> 2 files changed, 43 insertions(+)
>
> diff --git a/migration/migration.c b/migration/migration.c
> index 180552329c..f31fcbb0d5 100644
> --- a/migration/migration.c
> +++ b/migration/migration.c
> @@ -1448,6 +1448,33 @@ 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 */
> + ret = qemu_file_shutdown(ms->to_dst_file);
How did this fix the race I mentioned last time?
Dave
> + 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)) {
> diff --git a/qapi/migration.json b/qapi/migration.json
> index 451d8c572b..b8827d5ace 100644
> --- a/qapi/migration.json
> +++ b/qapi/migration.json
> @@ -1194,3 +1194,19 @@
> ##
> { '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: 2.12
> +##
> +{ 'command': 'migrate-pause', 'allow-oob': true }
> --
> 2.14.3
>
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK