On Wed, May 31, 2017 at 02:30:48PM -0700, Bart Van Assche wrote: > When verifying whether or not a blk-mq driver forgot to kick the > requeue list after having requeued a request it is important to > be able to verify the contents of the requeue list. Hence export > that list through debugfs. > > Signed-off-by: Bart Van Assche <[email protected]> > Reviewed-by: Hannes Reinecke <[email protected]> > Cc: Christoph Hellwig <[email protected]> > Cc: Omar Sandoval <[email protected]> > Cc: Ming Lei <[email protected]> > --- > block/blk-mq-debugfs.c | 32 ++++++++++++++++++++++++++++++++ > 1 file changed, 32 insertions(+) > > diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c > index d56ddd7a1285..8b06a12c1461 100644 > --- a/block/blk-mq-debugfs.c > +++ b/block/blk-mq-debugfs.c > @@ -308,6 +308,37 @@ int blk_mq_debugfs_rq_show(struct seq_file *m, void *v) > } > EXPORT_SYMBOL_GPL(blk_mq_debugfs_rq_show); > > +static void *queue_requeue_list_start(struct seq_file *m, loff_t *pos) > + __acquires(&q->requeue_lock) > +{ > + struct request_queue *q = m->private; > + > + spin_lock_irq(&q->requeue_lock); > + return seq_list_start(&q->requeue_list, *pos); > +} > + > +static void *queue_requeue_list_next(struct seq_file *m, void *v, loff_t > *pos) > +{ > + struct request_queue *q = m->private; > + > + return seq_list_next(v, &q->requeue_list, pos); > +} > + > +static void queue_requeue_list_stop(struct seq_file *m, void *v) > + __releases(&q->requeue_lock) > +{ > + struct request_queue *q = m->private; > + > + spin_unlock_irq(&q->requeue_lock); > +} > + > +static const struct seq_operations queue_requeue_list_seq_ops = { > + .start = queue_requeue_list_start, > + .next = queue_requeue_list_next, > + .stop = queue_requeue_list_stop, > + .show = blk_mq_debugfs_rq_show, > +}; > + > static void *hctx_dispatch_start(struct seq_file *m, loff_t *pos) > __acquires(&hctx->lock) > { > @@ -665,6 +696,7 @@ const struct file_operations blk_mq_debugfs_fops = { > > static const struct blk_mq_debugfs_attr blk_mq_debugfs_queue_attrs[] = { > {"poll_stat", 0400, queue_poll_stat_show}, > + {"requeue_list", 0400, .seq_ops = &queue_requeue_list_seq_ops}, > {"state", 0600, queue_state_show, queue_state_write}, > {}, > }; > -- > 2.12.2 >
Reviewed-by: Ming Lei <[email protected]> thanks, Ming
