[PATCH v5 05/10] block: avoid to use q->flush_rq directly

Ming Lei
2014-09-25T15:26:00Z

This patch trys to use local variable to access flush request,
so that we can convert to per-queue flush machinery a bit easier.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
---
block/blk-flush.c | 17 +++++++++--------
1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/block/blk-flush.c b/block/blk-flush.c
index a49ffbd..caf44756 100644
--- a/block/blk-flush.c
+++ b/block/blk-flush.c
@@ -223,7 +223,7 @@ static void flush_end_io(struct request *flush_rq, int error)

if (q->mq_ops) {
spin_lock_irqsave(&q->mq_flush_lock, flags);
- q->flush_rq->tag = -1;
+ flush_rq->tag = -1;
}

running = &q->flush_queue[q->flush_running_idx];
@@ -281,6 +281,7 @@ static bool blk_kick_flush(struct request_queue *q)
struct list_head *pending = &q->flush_queue[q->flush_pending_idx];
struct request *first_rq =
list_first_entry(pending, struct request, flush.list);
+ struct request *flush_rq = q->flush_rq;

/* C1 described at the top of this file */
if (q->flush_pending_idx != q->flush_running_idx || list_empty(pending))
@@ -298,16 +299,16 @@ static bool blk_kick_flush(struct request_queue *q)
*/
q->flush_pending_idx ^= 1;

- blk_rq_init(q, q->flush_rq);
+ blk_rq_init(q, flush_rq);
if (q->mq_ops)
- blk_mq_clone_flush_request(q->flush_rq, first_rq);
+ blk_mq_clone_flush_request(flush_rq, first_rq);

- q->flush_rq->cmd_type = REQ_TYPE_FS;
- q->flush_rq->cmd_flags = WRITE_FLUSH | REQ_FLUSH_SEQ;
- q->flush_rq->rq_disk = first_rq->rq_disk;
- q->flush_rq->end_io = flush_end_io;
+ flush_rq->cmd_type = REQ_TYPE_FS;
+ flush_rq->cmd_flags = WRITE_FLUSH | REQ_FLUSH_SEQ;
+ flush_rq->rq_disk = first_rq->rq_disk;
+ flush_rq->end_io = flush_end_io;

- return blk_flush_queue_rq(q->flush_rq, false);
+ return blk_flush_queue_rq(flush_rq, false);
}

static void flush_data_end_io(struct request *rq, int error)
--
1.7.9.5