On Thu, 12 Oct 2006 23:02:52 +0200 Jean Delvare <[EMAIL PROTECTED]> wrote:
> Hi Stephen, > > On 10/11/06, Stephen Hemminger wrote: > > On Wed, 11 Oct 2006, Jesse Brandeburg wrote: > > > On 10/11/06, Jean Delvare wrote: > > > > Let the e1000 driver report the most important statistics (rx/tx_bytes > > > > and rx/tx_packets) in real time, rather than every other second. This > > > > is similar to what the e100 driver is doing. > > > > (...) > > > > --- linux-2.6.19-rc1.orig/drivers/net/e1000/e1000_main.c > > > > 2006-10-11 10:53:49.000000000 +0200 > > > > +++ linux-2.6.19-rc1/drivers/net/e1000/e1000_main.c 2006-10-11 > > > > 11:34:41.000000000 +0200 > > > > @@ -3118,6 +3118,8 @@ > > > > e1000_tx_map(adapter, tx_ring, skb, first, > > > > max_per_txd, nr_frags, mss)); > > > > > > > > + adapter->net_stats.tx_packets++; > > > > + adapter->net_stats.tx_bytes += skb->len; > > > > netdev->trans_start = jiffies; > > > > > > this is the part I'm most worried about. as I believe it to be > > > incorrect for TSO packets. Maybe something like? > > > + if (skb_shinfo(skb)->gso_segs) > > > + adapter->net_stats.tx_packets += skb_shinfo(skb)->gso_segs; > > > + else > > > + adapter->net_stats.tx_packets++; > > > + adapter->net_stats.tx_bytes += skb->len; > > > netdev->trans_start = jiffies; > > > > > > skb len will still be off by some amount, because the skb->data > > > (header) is replicated across each gso segment but only counted once > > > this way, but hopefully someone will pipe up with a good way to > > > compute that. > > > > You might want to put the tx values in a per-cpu structure and > > sum later. Incrementing statistics can actually be a performance > > bottleneck on SMP tests, because it causes lots of cache thrashing. > > I don't really see how this would be implemented. Can you please point > me to other drivers which do it that way? > > Thanks, Loopback (drivers/net/loopback.c) does it, but it is simpler since it doesn't have to support multiple interfaces. In a normal driver you would have to use indirection and alloc_percpu() like af_inet.c does. -- Stephen Hemminger <[EMAIL PROTECTED]> - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
