Commit c865d848 authored by Vladimir Sementsov-Ogievskiy's avatar Vladimir Sementsov-Ogievskiy Committed by John Snow
Browse files

migration: add is_active_iterate handler 



Only-postcopy savevm states (dirty-bitmap) don't need live iteration, so
to disable them and stop transporting empty sections there is a new
savevm handler.

Signed-off-by: default avatarVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: default avatarJuan Quintela <quintela@redhat.com>
Reviewed-by: default avatarJohn Snow <jsnow@redhat.com>
Reviewed-by: default avatarFam Zheng <famz@redhat.com>
Message-id: 20180313180320.339796-10-vsementsov@virtuozzo.com
parent f0d64cb7

include/migration/register.h

+9 −0
Original line number Diff line number Diff line
@@ -26,6 +26,15 @@ typedef struct SaveVMHandlers { 
    bool (*is_active)(void *opaque);

    bool (*has_postcopy)(void *opaque);



    /* is_active_iterate

     * If it is not NULL then qemu_savevm_state_iterate will skip iteration if

     * it returns false. For example, it is needed for only-postcopy-states,

     * which needs to be handled by qemu_savevm_state_setup and

     * qemu_savevm_state_pending, but do not need iterations until not in

     * postcopy stage.

     */

    bool (*is_active_iterate)(void *opaque);



    /* This runs outside the iothread lock in the migration case, and

     * within the lock in the savevm case.  The callback had better only

     * use data that is local to the migration thread or protected

migration/savevm.c

+5 −0
Original line number Diff line number Diff line
@@ -1028,6 +1028,11 @@ int qemu_savevm_state_iterate(QEMUFile *f, bool postcopy) 
                continue;

            }

        }

        if (se->ops && se->ops->is_active_iterate) {

            if (!se->ops->is_active_iterate(se->opaque)) {

                continue;

            }

        }

        /*

         * In the postcopy phase, any device that doesn't know how to

         * do postcopy should have saved it's state in the _complete