Re: [PATCH] slip: Use net_device_stats from struct net_device

Tobias Klauser
2010-08-19T09:13:00Z

On 2010-08-19 at 10:49:51 +0200, Eric Dumazet <eric.dumazet@gmail.com> wrote:
> Le jeudi 19 août 2010 à 10:25 +0200, Tobias Klauser a écrit :
> > Use net_device->stats for stats instead of private variable copies in
> > struct slip.
> >
> > Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
> > ---
> > drivers/net/slip.c | 64 ++++++++++++++++++++++------------------------------
> > drivers/net/slip.h | 9 -------
> > 2 files changed, 27 insertions(+), 46 deletions(-)
>
>
> > @@ -561,36 +562,25 @@ static int sl_change_mtu(struct net_device *dev, int new_mtu)
> > static struct net_device_stats *
> > sl_get_stats(struct net_device *dev)
> > {
> > - static struct net_device_stats stats;
> > + struct net_device_stats *stats = &dev->stats;
> > struct slip *sl = netdev_priv(dev);
> > #ifdef SL_INCLUDE_CSLIP
> > struct slcompress *comp;
> > #endif
> >
> > - memset(&stats, 0, sizeof(struct net_device_stats));
> > -
> > - stats.rx_packets = sl->rx_packets;
> > - stats.tx_packets = sl->tx_packets;
> > - stats.rx_bytes = sl->rx_bytes;
> > - stats.tx_bytes = sl->tx_bytes;
> > - stats.rx_dropped = sl->rx_dropped;
> > - stats.tx_dropped = sl->tx_dropped;
> > - stats.tx_errors = sl->tx_errors;
> > - stats.rx_errors = sl->rx_errors;
> > - stats.rx_over_errors = sl->rx_over_errors;
> > #ifdef SL_INCLUDE_CSLIP
> > - stats.rx_fifo_errors = sl->rx_compressed;
> > - stats.tx_fifo_errors = sl->tx_compressed;
> > - stats.collisions = sl->tx_misses;
> > + stats->rx_fifo_errors = sl->rx_compressed;
> > + stats->tx_fifo_errors = sl->tx_compressed;
> > + stats->collisions = sl->tx_misses;
> > comp = sl->slcomp;
> > if (comp) {
> > - stats.rx_fifo_errors += comp->sls_i_compressed;
> > - stats.rx_dropped += comp->sls_i_tossed;
> > - stats.tx_fifo_errors += comp->sls_o_compressed;
> > - stats.collisions += comp->sls_o_misses;
> > + stats->rx_fifo_errors += comp->sls_i_compressed;
> > + stats->rx_dropped += comp->sls_i_tossed;
> > + stats->tx_fifo_errors += comp->sls_o_compressed;
> > + stats->collisions += comp->sls_o_misses;
> > }
> > -#endif /* CONFIG_INET */
> > - return (&stats);
> > +#endif
> > + return stats;
> > }
> >
>
> Hmm, this is wrong.
>
> Each time sl_get_stats() is called, you are adding stuff to dev->stats

Hmmm, yeah. Sorry for the mess. That's completely wrong.

> Quite frankly I dont think its a kernel-janitors@vger.kernel.org patch,
> its pretty normal netdev stuff.
>
> Please take a look at prior patch posted yesterday.
>
> http://marc.info/?l=linux-netdev&m=128213719605250&w=2
>
> Because either you should build your patch on top of it, or ask David to
> revert mine before ;)

Oops, I didn't notice that one. I'll rebuild my patch on top of it.

> I advise using a ndo_get_stats64() so that you can perform the adds on a
> private destination buffer.

I'll do that.

Thanks a lot
Tobias