On 2010-08-24 10:38, Philipp Reisner wrote: > Am Donnerstag, 12. August 2010, um 00:38:45 schrieb Dan Carpenter: >> dt is unsigned so it's never less than zero. We are calculating the >> elapsed time, and that's never less than zero (unless there is a bug or >> we invent time travel). The comparison here is just to guard against >> divide by zero bugs. >> >> Signed-off-by: Dan Carpenter <error27@xxxxxxxxx> >> >> diff --git a/drivers/block/drbd/drbd_proc.c >> b/drivers/block/drbd/drbd_proc.c index be3374b..4c0c4aa 100644 >> --- a/drivers/block/drbd/drbd_proc.c >> +++ b/drivers/block/drbd/drbd_proc.c >> @@ -118,7 +118,7 @@ static void drbd_syncer_progress(struct drbd_conf >> *mdev, struct seq_file *seq) /* mean speed since syncer started >> * we do account for PausedSync periods */ >> dt = (jiffies - mdev->rs_start - mdev->rs_paused) / HZ; >> - if (dt <= 0) >> + if (dt == 0) >> dt = 1; >> db = mdev->rs_total - rs_left; >> dbdt = Bit2KB(db/dt); > > Hi Dan, > > Please elaborate the improvement this patch brings. > dt can actually get negative, on jiffie wrap. I see > little value in displaying then a negative resync speed... Aren't all members unsigned long? If not, then you have another bug. -- Jens Axboe -- To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
