| Message ID | 4F729235.8040706@gmail.com |
|---|---|
| State | Rejected, archived |
| Delegated to: | David Miller |
| Headers | show |
On Tue, Mar 27, 2012 at 9:23 PM, Li Yu <raise.sail@gmail.com> wrote: > > It seem that we forget remove below two lines after copying code :) > > This update never impacts others. > > Sorry for last mail with legal notices improperly, I used wrong > mail. > > Signed-off-by Li Yu <bingtian.ly@taobao.com> > > diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c > index e886e2f..b2f8ada 100644 > --- a/net/ipv4/tcp_input.c > +++ b/net/ipv4/tcp_input.c > @@ -2169,8 +2169,6 @@ static void tcp_enter_frto_loss(struct sock *sk, > int allowed_segments, int flag) > /* For some reason this R-bit might get cleared? */ > if (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_RETRANS) > tp->retrans_out += tcp_skb_pcount(skb); > - /* ...enter this if branch just for the first segment */ > - flag |= FLAG_DATA_ACKED; The comment explicitly explains why the flag is marked for. > } else { > if (TCP_SKB_CB(skb)->sacked & TCPCB_RETRANS) > tp->undo_marker = 0; > -- > To unsubscribe from this list: send the line "unsubscribe netdev" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wed, Mar 28, 2012 at 12:23 AM, Li Yu <raise.sail@gmail.com> wrote: > > It seem that we forget remove below two lines after copying code :) > > This update never impacts others. The 'flag' variable will be used in later iterations of the tcp_for_write_queue() loop. The comment seems to quite sensibly indicate that the FLAG_DATA_ACKED bit is being set to avoid entering that branch of the if statement in later segments in the loop: 2168 if ((tp->frto_counter == 1) && !(flag & FLAG_DATA_ACKED)) { 2169 /* For some reason this R-bit might get cleared? */ 2170 if (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_RETRANS) 2171 tp->retrans_out += tcp_skb_pcount(skb); 2172 /* ...enter this if branch just for the first segment */ 2173 flag |= FLAG_DATA_ACKED; 2174 } else { The structure of the logic seems intact from the original commit that added this: http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=commitdiff;h=d1a54c6a0a3f9c2c4ef71982d89b8571bd9eaa51 neal -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
于 2012年03月28日 13:29, Neal Cardwell 写道: > On Wed, Mar 28, 2012 at 12:23 AM, Li Yu<raise.sail@gmail.com> wrote: >> >> It seem that we forget remove below two lines after copying code :) >> >> This update never impacts others. > > The 'flag' variable will be used in later iterations of the > tcp_for_write_queue() loop. The comment seems to quite sensibly > indicate that the FLAG_DATA_ACKED bit is being set to avoid entering > that branch of the if statement in later segments in the loop: > > 2168 if ((tp->frto_counter == 1)&& !(flag& FLAG_DATA_ACKED)) { > 2169 /* For some reason this R-bit might get cleared? */ > 2170 if (TCP_SKB_CB(skb)->sacked& TCPCB_SACKED_RETRANS) > 2171 tp->retrans_out += tcp_skb_pcount(skb); > 2172 /* ...enter this if branch just for the > first segment */ > 2173 flag |= FLAG_DATA_ACKED; > 2174 } else { > > The structure of the logic seems intact from the original commit that > added this: > > http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=commitdiff;h=d1a54c6a0a3f9c2c4ef71982d89b8571bd9eaa51 > Sorry for spent time on this, it it account for F-RTO retransmitted segment here. Yu > neal > -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wed, 2012-03-28 at 14:54 +0800, Li Yu wrote: > Sorry for spent time on this, it it account for F-RTO retransmitted > segment here. I dont believe its waste of time having several eyes on this code. Thanks -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index e886e2f..b2f8ada 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -2169,8 +2169,6 @@ static void tcp_enter_frto_loss(struct sock *sk, int allowed_segments, int flag) /* For some reason this R-bit might get cleared? */ if (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_RETRANS) tp->retrans_out += tcp_skb_pcount(skb); - /* ...enter this if branch just for the first segment */ - flag |= FLAG_DATA_ACKED; } else { if (TCP_SKB_CB(skb)->sacked & TCPCB_RETRANS)