Messages in this thread | | | Date | Wed, 13 Dec 2017 08:13:12 -0800 | From | Tejun Heo <> | Subject | Re: [PATCH 1/6] blk-mq: protect completion path with RCU |
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Hello,
On Wed, Dec 13, 2017 at 11:30:48AM +0800, jianchao.wang wrote: > > + } else { > > + srcu_idx = srcu_read_lock(hctx->queue_rq_srcu); > > + if (!blk_mark_rq_complete(rq)) > > + __blk_mq_complete_request(rq); > > + srcu_read_unlock(hctx->queue_rq_srcu, srcu_idx); > > The __blk_mq_complete_request() could be executed in irq context. There should not be any > sleeping operations in it. If just synchronize with the timeout path to ensure the aborted_gstate > to be seen, only rcu is needed here ,as well as the blk_mq_timeout_work.
Sure, but it's just a lot cleaner to use the same to protect both issue and completion; otherwise, whoever who wants to synchronize against them have to do awkward double rcu locking.
Thanks.
-- tejun
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