Commit fd0ff8aa authored May 23, 2006 by Jens Axboe Committed by Linus Torvalds May 23, 2006

[PATCH] blk: fix gendisk->in_flight accounting during barrier sequence



While executing barrrier sequence, the bar_rq which carries actual
write was accounted as normal IO on completion, while it wasn't on
queueing.  This caused gendisk->in_flight to be decremented by 1 after
each barrier thus messed up statistics.

This patch makes bar_rq not accounted as normal IO.  As the containing
barrier request as a whole is accounted, part of it shouldn't be.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

parent 0f041082

block/ll_rw_blk.c

+6 −1

Original line number	Diff line number	Diff line
		@@ -3452,7 +3452,12 @@ void end_that_request_last(struct request *req, int uptodate)
		if (unlikely(laptop_mode) && blk_fs_request(req))
		laptop_io_completion();

		if (disk && blk_fs_request(req)) {
		/*
		* Account IO completion. bar_rq isn't accounted as a normal
		* IO on queueing nor completion. Accounting the containing
		* request is enough.
		*/
		if (disk && blk_fs_request(req) && req != &req->q->bar_rq) {
		unsigned long duration = jiffies - req->start_time;
		const int rw = rq_data_dir(req);