On Tue, Aug 24, 2021 at 7:27 PM Peter Xu <pet...@redhat.com> wrote:
> An internal version that removes -only-migratable implications. It can be
> used
> for temporary migration blockers like dump-guest-memory.
>
> Signed-off-by: Peter Xu <pet...@redhat.com>
>
Reviewed-by: Marc-André Lureau <marcandre.lur...@redhat.com>
---
> include/migration/blocker.h | 16 ++++++++++++++++
> migration/migration.c | 21 +++++++++++++--------
> 2 files changed, 29 insertions(+), 8 deletions(-)
>
> diff --git a/include/migration/blocker.h b/include/migration/blocker.h
> index acd27018e9..9cebe2ba06 100644
> --- a/include/migration/blocker.h
> +++ b/include/migration/blocker.h
> @@ -25,6 +25,22 @@
> */
> int migrate_add_blocker(Error *reason, Error **errp);
>
> +/**
> + * @migrate_add_blocker_internal - prevent migration from proceeding
> without
> + * only-migrate implications
> + *
> + * @reason - an error to be returned whenever migration is attempted
> + *
> + * @errp - [out] The reason (if any) we cannot block migration right now.
> + *
> + * @returns - 0 on success, -EBUSY on failure, with errp set.
> + *
> + * Some of the migration blockers can be temporary (e.g., for a few
> seconds),
> + * so it shouldn't need to conflict with "-only-migratable". For those
> cases,
> + * we can call this function rather than @migrate_add_blocker().
> + */
> +int migrate_add_blocker_internal(Error *reason, Error **errp);
> +
> /**
> * @migrate_del_blocker - remove a blocking error from migration
> *
> diff --git a/migration/migration.c b/migration/migration.c
> index 041b8451a6..41429680c2 100644
> --- a/migration/migration.c
> +++ b/migration/migration.c
> @@ -2053,15 +2053,8 @@ void migrate_init(MigrationState *s)
> s->threshold_size = 0;
> }
>
> -int migrate_add_blocker(Error *reason, Error **errp)
> +int migrate_add_blocker_internal(Error *reason, Error **errp)
> {
> - if (only_migratable) {
> - error_propagate_prepend(errp, error_copy(reason),
> - "disallowing migration blocker "
> - "(--only-migratable) for: ");
> - return -EACCES;
> - }
> -
> if (migration_is_idle()) {
> migration_blockers = g_slist_prepend(migration_blockers, reason);
> return 0;
> @@ -2073,6 +2066,18 @@ int migrate_add_blocker(Error *reason, Error **errp)
> return -EBUSY;
> }
>
> +int migrate_add_blocker(Error *reason, Error **errp)
> +{
> + if (only_migratable) {
> + error_propagate_prepend(errp, error_copy(reason),
> + "disallowing migration blocker "
> + "(--only-migratable) for: ");
> + return -EACCES;
> + }
> +
> + return migrate_add_blocker_internal(reason, errp);
> +}
> +
> void migrate_del_blocker(Error *reason)
> {
> migration_blockers = g_slist_remove(migration_blockers, reason);
> --
> 2.31.1
>
>
