Francois Romieu wrote: > Two thirds of packets are lost because of misalignment. Users of > Asus laptop did apparently not notice it. > > Reported on Gigabyte GA-945GM-S2. > > Fix for http://bugzilla.kernel.org/show_bug.cgi?id=7517 > > Signed-off-by: Francois Romieu <[EMAIL PROTECTED]> > --- > drivers/net/r8169.c | 4 ++-- > 1 files changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/net/r8169.c b/drivers/net/r8169.c > index 0b57050..2379d83 100644 > --- a/drivers/net/r8169.c > +++ b/drivers/net/r8169.c > @@ -2018,7 +2018,7 @@ static int rtl8169_alloc_rx_skb(struct p > if (!skb) > goto err_out; > > - skb_reserve(skb, align); > + skb_reserve(skb, (align - 1) & (u32)skb->data); > *sk_buff = skb; > > mapping = pci_map_single(pdev, skb->data, rx_buf_sz, > @@ -2486,7 +2486,7 @@ static inline int rtl8169_try_rx_copy(st > > skb = dev_alloc_skb(pkt_size + align); > if (skb) { > - skb_reserve(skb, align); > + skb_reserve(skb, (align - 1) & (u32)skb->data); > eth_copy_and_sum(skb, sk_buff[0]->data, pkt_size, 0); > *sk_buff = skb; > rtl8169_mark_to_asic(desc, rx_buf_sz);
This patch caused a drop in throughput from 178 Mbits/sec to 135 Mbits/sec on an Intel XScale IXP465. It seems like there is some confusion about what the align parameter here means. It was originally an offset from an aligned address so that the IP header aligned, and this patch changes it to the alignment of the ethernet header. But align is still set to NET_IP_ALIGN for some chips. - 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
