On Thu, Apr 25, 2019 at 07:32:34AM +0200, Christoph Hellwig wrote: > On Thu, Apr 25, 2019 at 08:53:34AM +0800, Ming Lei wrote: > > It isn't in other callers of blk_mq_sched_insert_requests(), it is just > > needed in some corner case like flush plug context. > > > > For other callers of blk_mq_sched_insert_requests(), it is guaranteed > > that request queue's ref is held. > > In both Linus' tree and Jens' for-5.2 tree I only see these two > callers of blk_mq_sched_insert_requests. What am I missing?
OK, what I meant is that the issue is flush plug context specific. And I didn't notice that this function is only called by blk_mq_flush_plug_list(). Then it is fine to move the percpu_ref_get()/percpu_ref_put() into the function, better with comment on this issue. Thanks, Ming
