Commit 80fa2c75 authored by Kevin Wolf's avatar Kevin Wolf
Browse files

job: Add reference counting 



This moves reference counting from BlockJob to Job.

In order to keep calling the BlockJob cleanup code when the job is
deleted via job_unref(), introduce a new JobDriver.free callback. Every
block job must use block_job_free() for this callback, this is asserted
in block_job_create().

Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
Reviewed-by: default avatarMax Reitz <mreitz@redhat.com>
Reviewed-by: default avatarJohn Snow <jsnow@redhat.com>
parent a50c2ab8

block/backup.c

+1 −0
Original line number Diff line number Diff line
@@ -526,6 +526,7 @@ static const BlockJobDriver backup_job_driver = { 
    .job_driver = {

        .instance_size          = sizeof(BackupBlockJob),

        .job_type               = JOB_TYPE_BACKUP,

        .free                   = block_job_free,

    },

    .start                  = backup_run,

    .commit                 = backup_commit,

block/commit.c

+1 −0
Original line number Diff line number Diff line
@@ -218,6 +218,7 @@ static const BlockJobDriver commit_job_driver = { 
    .job_driver = {

        .instance_size = sizeof(CommitBlockJob),

        .job_type      = JOB_TYPE_COMMIT,

        .free          = block_job_free,

    },

    .start         = commit_run,

};

block/mirror.c

+2 −0
Original line number Diff line number Diff line
@@ -989,6 +989,7 @@ static const BlockJobDriver mirror_job_driver = { 
    .job_driver = {

        .instance_size          = sizeof(MirrorBlockJob),

        .job_type               = JOB_TYPE_MIRROR,

        .free                   = block_job_free,

    },

    .start                  = mirror_run,

    .complete               = mirror_complete,
@@ -1001,6 +1002,7 @@ static const BlockJobDriver commit_active_job_driver = { 
    .job_driver = {

        .instance_size          = sizeof(MirrorBlockJob),

        .job_type               = JOB_TYPE_COMMIT,

        .free                   = block_job_free,

    },

    .start                  = mirror_run,

    .complete               = mirror_complete,

block/stream.c

+1 −0
Original line number Diff line number Diff line
@@ -212,6 +212,7 @@ static const BlockJobDriver stream_job_driver = { 
    .job_driver = {

        .instance_size = sizeof(StreamBlockJob),

        .job_type      = JOB_TYPE_STREAM,

        .free          = block_job_free,

    },

    .start         = stream_run,

};

blockjob.c

+21 −27
Original line number Diff line number Diff line
@@ -190,31 +190,25 @@ static void block_job_resume(BlockJob *job) 
    block_job_enter_cond(job, block_job_timer_not_pending);

}



void block_job_ref(BlockJob *job)

{

    ++job->refcnt;

}



static void block_job_attached_aio_context(AioContext *new_context,

                                           void *opaque);

static void block_job_detach_aio_context(void *opaque);



void block_job_unref(BlockJob *job)

void block_job_free(Job *job)

{

    if (--job->refcnt == 0) {

        assert(job->job.status == JOB_STATUS_NULL);

        assert(!job->txn);

        BlockDriverState *bs = blk_bs(job->blk);

    BlockJob *bjob = container_of(job, BlockJob, job);

    BlockDriverState *bs = blk_bs(bjob->blk);



    assert(!bjob->txn);



    bs->job = NULL;

        block_job_remove_all_bdrv(job);

        blk_remove_aio_context_notifier(job->blk,

    block_job_remove_all_bdrv(bjob);

    blk_remove_aio_context_notifier(bjob->blk,

                                    block_job_attached_aio_context,

                                        block_job_detach_aio_context, job);

        blk_unref(job->blk);

        error_free(job->blocker);

        assert(!timer_pending(&job->sleep_timer));

        job_delete(&job->job);

    }

                                    block_job_detach_aio_context, bjob);

    blk_unref(bjob->blk);

    error_free(bjob->blocker);

    assert(!timer_pending(&bjob->sleep_timer));

}



static void block_job_attached_aio_context(AioContext *new_context,
@@ -245,7 +239,7 @@ static void block_job_detach_aio_context(void *opaque) 
    BlockJob *job = opaque;



    /* In case the job terminates during aio_poll()... */

    block_job_ref(job);

    job_ref(&job->job);



    block_job_pause(job);
@@ -253,7 +247,7 @@ static void block_job_detach_aio_context(void *opaque) 
        block_job_drain(job);

    }



    block_job_unref(job);

    job_unref(&job->job);

}



static char *child_job_get_parent_desc(BdrvChild *c)
@@ -367,7 +361,7 @@ static void block_job_decommission(BlockJob *job) 
    job->deferred_to_main_loop = true;

    block_job_txn_del_job(job);

    job_state_transition(&job->job, JOB_STATUS_NULL);

    block_job_unref(job);

    job_unref(&job->job);

}



static void block_job_do_dismiss(BlockJob *job)
@@ -506,14 +500,14 @@ static int block_job_finish_sync(BlockJob *job, 


    assert(blk_bs(job->blk)->job == job);



    block_job_ref(job);

    job_ref(&job->job);



    if (finish) {

        finish(job, &local_err);

    }

    if (local_err) {

        error_propagate(errp, local_err);

        block_job_unref(job);

        job_unref(&job->job);

        return -EBUSY;

    }

    /* block_job_drain calls block_job_enter, and it should be enough to
@@ -526,7 +520,7 @@ static int block_job_finish_sync(BlockJob *job, 
        aio_poll(qemu_get_aio_context(), true);

    }

    ret = (job->cancelled && job->ret == 0) ? -ECANCELED : job->ret;

    block_job_unref(job);

    job_unref(&job->job);

    return ret;

}
@@ -909,6 +903,7 @@ void *block_job_create(const char *job_id, const BlockJobDriver *driver, 
    }



    assert(is_block_job(&job->job));

    assert(job->job.driver->free == &block_job_free);



    job->driver        = driver;

    job->blk           = blk;
@@ -917,7 +912,6 @@ void *block_job_create(const char *job_id, const BlockJobDriver *driver, 
    job->busy          = false;

    job->paused        = true;

    job->pause_count   = 1;

    job->refcnt        = 1;

    job->auto_finalize = !(flags & BLOCK_JOB_MANUAL_FINALIZE);

    job->auto_dismiss  = !(flags & BLOCK_JOB_MANUAL_DISMISS);

    aio_timer_init(qemu_get_aio_context(), &job->sleep_timer,