Re: [Drbd-dev] [patch] drbd: cleanup: change "<= 0" to "== 0"

[Philipp Reisner <philipp.reisner@linbit.com>]

Am Dienstag, 24. August 2010, um 10:41:31 schrieb Jens Axboe:
> 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@gmail.com>
> >> 
> >> 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.

Um, well that is right. Ok, patch goes in.

Best,
 Phil
-- 
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