On Fri, Nov 16, 2018 at 06:05:21AM -0800, Greg Kroah-Hartman wrote:
On Fri, Nov 16, 2018 at 07:23:10PM +0800, Ming Lei wrote:
@@ -456,7 +456,7 @@ struct request_queue { /* * mq queue kobject */
- struct kobject mq_kobj;
- struct kobject *mq_kobj;
What is this kobject even used for? It wasn't obvious at all from this patch, why is it needed if you are not using it to reference count the larger structure here?
All attributes and kobjects under /sys/block/$DEV/mq are covered by this kobject actually, and all are for exposing blk-mq specific information, but now there is only blk-mq, and legacy io path is removed.
That is why I mentioned we may remove this kobject last time and move all under /sys/block/$DEV/queue, however you thought that may break some userspace.
If we want to backport them to stable, this patch may be a bit easier to go.
Thanks, Ming