block: track request size in blk_issue_stat

Currently there is no way to know the request size when the request is
finished. Next patch will need this info. We could add extra field to
record the size, but blk_issue_stat has enough space to record it, so
this patch just overloads blk_issue_stat. With this, we will have 49bits
to track time, which still is very long time.

Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This commit is contained in:
Shaohua Li
2017-03-27 15:19:41 -07:00
committed by Jens Axboe
parent ec80991d6f
commit 88eeca495b
5 changed files with 38 additions and 19 deletions
+1 -1
View File
@@ -488,7 +488,7 @@ void blk_mq_start_request(struct request *rq)
trace_block_rq_issue(q, rq);
if (test_bit(QUEUE_FLAG_STATS, &q->queue_flags)) {
blk_stat_set_issue_time(&rq->issue_stat);
blk_stat_set_issue(&rq->issue_stat, blk_rq_sectors(rq));
rq->rq_flags |= RQF_STATS;
wbt_issue(q->rq_wb, &rq->issue_stat);
}