blk-mq: do not initialize req->special
Drivers can reach their private data easily using the blk_mq_rq_to_pdu
helper and don't need req->special. By not initializing it code can
be simplified nicely, and we also shave off a few more instructions from
the I/O path.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/block/blk-flush.c b/block/blk-flush.c
index 77f2045..0e42adc 100644
--- a/block/blk-flush.c
+++ b/block/blk-flush.c
@@ -306,22 +306,16 @@
*/
q->flush_pending_idx ^= 1;
+ blk_rq_init(q, q->flush_rq);
if (q->mq_ops) {
- struct blk_mq_ctx *ctx = first_rq->mq_ctx;
- struct blk_mq_hw_ctx *hctx = q->mq_ops->map_queue(q, ctx->cpu);
-
- blk_mq_rq_init(hctx, q->flush_rq);
- q->flush_rq->mq_ctx = ctx;
-
/*
* Reuse the tag value from the fist waiting request,
* with blk-mq the tag is generated during request
* allocation and drivers can rely on it being inside
* the range they asked for.
*/
+ q->flush_rq->mq_ctx = first_rq->mq_ctx;
q->flush_rq->tag = first_rq->tag;
- } else {
- blk_rq_init(q, q->flush_rq);
}
q->flush_rq->cmd_type = REQ_TYPE_FS;