Re: [PATCH] mac80211: Fix output of minstrels rc_stats

[Pavel Roskin <proski@gnu.org>]

On Mon, 2009-08-24 at 10:57 -0700, Joe Perches wrote:
> On Mon, 2009-08-24 at 19:42 +0200, Arnd Hannemann wrote:
> > An integer overflow in the minstrel debug code prevented the
> > throughput to be displayed correctly. This patch fixes that,
> > by swaping the division and multiplication.
> > 
> > Signed-off-by: Arnd Hannemann <hannemann@nets.rwth-aachen.de>
> > ---
> >  net/mac80211/rc80211_minstrel_debugfs.c |    2 +-
> >  1 files changed, 1 insertions(+), 1 deletions(-)
> > 
> > diff --git a/net/mac80211/rc80211_minstrel_debugfs.c b/net/mac80211/rc80211_minstrel_debugfs.c
> > index 98f4807..caf9453 100644
> > --- a/net/mac80211/rc80211_minstrel_debugfs.c
> > +++ b/net/mac80211/rc80211_minstrel_debugfs.c
> > @@ -83,7 +83,7 @@ minstrel_stats_open(struct inode *inode, struct file *file)
> >  		p += sprintf(p, "%3u%s", mr->bitrate / 2,
> >  				(mr->bitrate & 1 ? ".5" : "  "));
> >  
> > -		tp = ((mr->cur_tp * 96) / 18000) >> 10;
> > +		tp = ((mr->cur_tp / 18000) * 96) >> 10;
> 
> Maybe do_div instead?

How about this?

tp = mr->cur_tp / ((18000 << 10) / 96);

((18000 << 10) / 96) is exactly 192000.

-- 
Regards,
Pavel Roskin