blk-mq: Revert "blk-mq: reimplement blk_mq_hw_queue_mapped"

This reverts commit 127276c6ce.

When all CPUs of one hw queue become offline, there still may have IOs
not completed from this hctx. But blk_mq_hw_queue_mapped() is called in
blk_mq_queue_tag_busy_iter(), which is used for iterating request in timeout
handler, timeout event will be missed on the inactive hctx, then request may
never be completed.

Also the replementation of blk_mq_hw_queue_mapped() doesn't match the helper's
name any more, and it should have been named as blk_mq_hw_queue_active().

Even other callers need further verification about this reimplemenation.

So revert this patch now, and we can improve hw queue activate/inactivate event
after adequent researching and test.

Cc: Stefan Haberland <sth@linux.vnet.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Christoph Hellwig <hch@lst.de>
Reported-by: Jens Axboe <axboe@kernel.dk>
Fixes: 	127276c6ce ("blk-mq: reimplement blk_mq_hw_queue_mapped")
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Ming Lei 2018-04-11 18:47:44 +08:00 committed by Jens Axboe
parent 37f9579f4c
commit 2434af79c8
1 changed files with 1 additions and 1 deletions

View File

@ -181,7 +181,7 @@ static inline bool blk_mq_hctx_stopped(struct blk_mq_hw_ctx *hctx)
static inline bool blk_mq_hw_queue_mapped(struct blk_mq_hw_ctx *hctx)
{
return cpumask_first_and(hctx->cpumask, cpu_online_mask) < nr_cpu_ids;
return hctx->nr_ctx && hctx->tags;
}
void blk_mq_in_flight(struct request_queue *q, struct hd_struct *part,