block: move iostat check into blk_acount_io_start()

Rather than have blk_do_io_stat() check for both RQF_IO_STAT and whether
the request is a passthrough requests every time, move both of those
checks into blk_account_io_start(). Then blk_do_io_stat() can be reduced
to just checking for RQF_IO_STAT.

Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Anuj Gupta <anuj20.g@samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/block/blk-mq.c b/block/blk-mq.c
index cf626e061dd7747cbdebfbd5aba037ac8ef92521..6a339942948ae33115b395ce9493b0854131a19b 100644 (file)
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -359,8 +359,6 @@ static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data,
 
        if (data->flags & BLK_MQ_REQ_PM)
                data->rq_flags |= RQF_PM;
-       if (blk_queue_io_stat(q))
-               data->rq_flags |= RQF_IO_STAT;
        rq->rq_flags = data->rq_flags;
 
        if (data->rq_flags & RQF_SCHED_TAGS) {
@@ -1000,24 +998,28 @@ static inline void blk_account_io_start(struct request *req)
 {
        trace_block_io_start(req);
 
-       if (blk_do_io_stat(req)) {
-               /*
-                * All non-passthrough requests are created from a bio with one
-                * exception: when a flush command that is part of a flush sequence
-                * generated by the state machine in blk-flush.c is cloned onto the
-                * lower device by dm-multipath we can get here without a bio.
-                */
-               if (req->bio)
-                       req->part = req->bio->bi_bdev;
-               else
-                       req->part = req->q->disk->part0;
+       if (!blk_queue_io_stat(req->q))
+               return;
+       if (blk_rq_is_passthrough(req))
+               return;
 
-               part_stat_lock();
-               update_io_ticks(req->part, jiffies, false);
-               part_stat_local_inc(req->part,
-                                   in_flight[op_is_write(req_op(req))]);
-               part_stat_unlock();
-       }
+       req->rq_flags |= RQF_IO_STAT;
+
+       /*
+        * All non-passthrough requests are created from a bio with one
+        * exception: when a flush command that is part of a flush sequence
+        * generated by the state machine in blk-flush.c is cloned onto the
+        * lower device by dm-multipath we can get here without a bio.
+        */
+       if (req->bio)
+               req->part = req->bio->bi_bdev;
+       else
+               req->part = req->q->disk->part0;
+
+       part_stat_lock();
+       update_io_ticks(req->part, jiffies, false);
+       part_stat_local_inc(req->part, in_flight[op_is_write(req_op(req))]);
+       part_stat_unlock();
 }
 
 static inline void __blk_mq_end_request_acct(struct request *rq, u64 now)

diff --git a/block/blk.h b/block/blk.h
index c718e4291db0624d5cf02233f3700dff914b10e3..84178e535533b40276d3e690e109be7a6fb7a3c8 100644 (file)
--- a/block/blk.h
+++ b/block/blk.h
@@ -413,7 +413,7 @@ int blk_dev_init(void);
  */
 static inline bool blk_do_io_stat(struct request *rq)
 {
-       return (rq->rq_flags & RQF_IO_STAT) && !blk_rq_is_passthrough(rq);
+       return rq->rq_flags & RQF_IO_STAT;
 }
 
 void update_io_ticks(struct block_device *part, unsigned long now, bool end);