Commit b740d98f authored Nov 10, 2005 by Tejun Heo Committed by Jens Axboe Nov 12, 2005

[BLOCK] cfq-iosched: fix slice_left calculation



When cfq slice expires, remainder of slice is calculated and stored in
cfqq->slice_left.  Current code calculates the opposite of remainder -
how many jiffies the cfqq has used past slice end.  This patch fixes
the bug.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jens Axboe <axboe@suse.de>

parent be561235

block/cfq-iosched.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -861,8 +861,8 @@ __cfq_slice_expired(struct cfq_data cfqd, struct cfq_queue cfqq,
		* store what was left of this slice, if the queue idled out
		* or was preempted
		*/
		if (time_after(now, cfqq->slice_end))
		cfqq->slice_left = now - cfqq->slice_end;
		if (time_after(cfqq->slice_end, now))
		cfqq->slice_left = cfqq->slice_end - now;
		else
		cfqq->slice_left = 0;