blk-mq: remove REQ_END
Pass an explicit parameter for the last request in a batch to ->queue_rq
instead of using a request flag. Besides being a cleaner and non-stateful
interface this is also required for the next patch, which fixes the blk-mq
I/O submission code to not start a time too early.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/block/blk-mq.c b/block/blk-mq.c
index e743d28..32b4797 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -384,7 +384,7 @@
}
EXPORT_SYMBOL(blk_mq_complete_request);
-static void blk_mq_start_request(struct request *rq, bool last)
+static void blk_mq_start_request(struct request *rq)
{
struct request_queue *q = rq->q;
@@ -421,16 +421,6 @@
*/
rq->nr_phys_segments++;
}
-
- /*
- * Flag the last request in the series so that drivers know when IO
- * should be kicked off, if they don't do it on a per-request basis.
- *
- * Note: the flag isn't the only condition drivers should do kick off.
- * If drive is busy, the last request might not have the bit set.
- */
- if (last)
- rq->cmd_flags |= REQ_END;
}
static void __blk_mq_requeue_request(struct request *rq)
@@ -440,8 +430,6 @@
trace_block_rq_requeue(q, rq);
clear_bit(REQ_ATOM_STARTED, &rq->atomic_flags);
- rq->cmd_flags &= ~REQ_END;
-
if (q->dma_drain_size && blk_rq_bytes(rq))
rq->nr_phys_segments--;
}
@@ -755,9 +743,9 @@
rq = list_first_entry(&rq_list, struct request, queuelist);
list_del_init(&rq->queuelist);
- blk_mq_start_request(rq, list_empty(&rq_list));
+ blk_mq_start_request(rq);
- ret = q->mq_ops->queue_rq(hctx, rq);
+ ret = q->mq_ops->queue_rq(hctx, rq, list_empty(&rq_list));
switch (ret) {
case BLK_MQ_RQ_QUEUE_OK:
queued++;
@@ -1198,14 +1186,14 @@
int ret;
blk_mq_bio_to_request(rq, bio);
- blk_mq_start_request(rq, true);
+ blk_mq_start_request(rq);
/*
* For OK queue, we are done. For error, kill it. Any other
* error (busy), just add it to our list as we previously
* would have done
*/
- ret = q->mq_ops->queue_rq(data.hctx, rq);
+ ret = q->mq_ops->queue_rq(data.hctx, rq, true);
if (ret == BLK_MQ_RQ_QUEUE_OK)
goto done;
else {