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

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

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...

Best,
 Phil
-- 
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