[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>
This commit is contained in:
Tejun Heo 2005-11-10 18:20:16 +01:00 committed by Jens Axboe
parent be56123568
commit b740d98f56

View File

@ -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;