Re: [PATCH net-next 3/5] netxen: make 64 bit stats safe on 32 bit platform

[Stephen Hemminger <stephen.hemminger@vyatta.com>]

> On Mon, 2011-06-20 at 13:35 -0700, Stephen Hemminger wrote:
> 
> > Use stats_update wrapper to avoid problems where 64 bit statistic
> > update is not atomic on 32 bit platform.
> [...]
> > @@ -2115,11 +2117,17 @@ static struct rtnl_link_stats64 *netxen_
> >  						      struct rtnl_link_stats64 *stats)
> >  {
> >  	struct netxen_adapter *adapter = netdev_priv(netdev);
> > + unsigned int start;
> > + + do {
> > + start = u64_stats_fetch_begin(&adapter->stats.syncp);
> > + + stats->rx_packets = adapter->stats.rx_pkts +
> > adapter->stats.lro_pkts; + stats->tx_packets =
> > adapter->stats.xmitfinished; + stats->rx_bytes =
> > adapter->stats.rxbytes; + stats->tx_bytes = adapter->stats.txbytes;
> > + } while (u64_stats_fetch_retry(&adapter->stats.syncp, start));
> >
> > - stats->rx_packets = adapter->stats.rx_pkts +
> > adapter->stats.lro_pkts; - stats->tx_packets =
> > adapter->stats.xmitfinished; - stats->rx_bytes =
> > adapter->stats.rxbytes; - stats->tx_bytes = adapter->stats.txbytes;
> >  	stats->rx_dropped = adapter->stats.rxdropped;
> >  	stats->tx_dropped = adapter->stats.txdropped;
> 
> netxen_nic_get_ethtool_stats() should also be fixed.
> 
> The 'txdropped' and 'csummed' stats are also 64-bit and updated on the
> data path. ('rxdropped' isn't updated at all, AFAICS.)

Since they are error counters, just changing them to unsigned long is
easier.