jobs: utilize job_exit shim

Utilize the job_exit shim by not calling job_defer_to_main_loop, and
where applicable, converting the deferred callback into the job_exit
callback.

This converts backup, stream, create, and the unit tests all at once.
Most of these jobs do not see any changes to the order in which they
clean up their resources, except the test-blockjob-txn test, which
now puts down its bs before job_completed is called.

This is safe for the same reason the reordering in the mirror job is
safe, because job_completed no longer runs under two locks, making
the unref safe even if it causes a flush.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20180830015734.19765-7-jsnow@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>

1 files changed, 3 insertions, 11 deletions

diff --git a/block/create.c b/block/create.c
index 26a385c6c7..95341219ef 100644
--- a/block/create.c
+++ b/block/create.c
@@ -34,28 +34,20 @@ typedef struct BlockdevCreateJob {
     Job common;
     BlockDriver *drv;
     BlockdevCreateOptions *opts;
-    int ret;
 } BlockdevCreateJob;
 
-static void blockdev_create_complete(Job *job, void *opaque)
-{
-    BlockdevCreateJob *s = container_of(job, BlockdevCreateJob, common);
-
-    job_completed(job, s->ret);
-}
-
 static int coroutine_fn blockdev_create_run(Job *job, Error **errp)
 {
     BlockdevCreateJob *s = container_of(job, BlockdevCreateJob, common);
+    int ret;
 
     job_progress_set_remaining(&s->common, 1);
-    s->ret = s->drv->bdrv_co_create(s->opts, errp);
+    ret = s->drv->bdrv_co_create(s->opts, errp);
     job_progress_update(&s->common, 1);
 
     qapi_free_BlockdevCreateOptions(s->opts);
-    job_defer_to_main_loop(&s->common, blockdev_create_complete, NULL);
 
-    return s->ret;
+    return ret;
 }
 
 static const JobDriver blockdev_create_job_driver = {