From: Ilpo Järvinen Date: Thu, 20 Sep 2007 18:33:43 +0000 (-0700) Subject: [TCP]: Cleanup tcp_tso_acked and tcp_clean_rtx_queue X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=7c46a03e67d11d917d6c3dbf501b465b2ca97a6f;p=openwrt%2Fstaging%2Fblogic.git [TCP]: Cleanup tcp_tso_acked and tcp_clean_rtx_queue Implements following cleanups: - Comment re-placement (CodingStyle) - tcp_tso_acked() local (wrapper-like) variable removal (readability) - __-types removed (IMHO they make local variables jumpy looking and just was space) - acked -> flag (naming conventions elsewhere in TCP code) - linebreak adjustments (readability) - nested if()s combined (reduced indentation) - clarifying newlines added Signed-off-by: Ilpo Järvinen Signed-off-by: David S. Miller --- diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 4238ed98acb9..8fe754be8076 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -2525,55 +2525,49 @@ static void tcp_rearm_rto(struct sock *sk) } } +/* If we get here, the whole TSO packet has not been acked. */ static u32 tcp_tso_acked(struct sock *sk, struct sk_buff *skb) { struct tcp_sock *tp = tcp_sk(sk); - struct tcp_skb_cb *scb = TCP_SKB_CB(skb); - __u32 seq = tp->snd_una; - __u32 packets_acked; + u32 packets_acked; - /* If we get here, the whole TSO packet has not been - * acked. - */ - BUG_ON(!after(scb->end_seq, seq)); + BUG_ON(!after(TCP_SKB_CB(skb)->end_seq, tp->snd_una)); packets_acked = tcp_skb_pcount(skb); - if (tcp_trim_head(sk, skb, seq - scb->seq)) + if (tcp_trim_head(sk, skb, tp->snd_una - TCP_SKB_CB(skb)->seq)) return 0; packets_acked -= tcp_skb_pcount(skb); if (packets_acked) { BUG_ON(tcp_skb_pcount(skb) == 0); - BUG_ON(!before(scb->seq, scb->end_seq)); + BUG_ON(!before(TCP_SKB_CB(skb)->seq, TCP_SKB_CB(skb)->end_seq)); } return packets_acked; } -/* Remove acknowledged frames from the retransmission queue. */ -static int tcp_clean_rtx_queue(struct sock *sk, __s32 *seq_rtt_p) +/* Remove acknowledged frames from the retransmission queue. If our packet + * is before the ack sequence we can discard it as it's confirmed to have + * arrived at the other end. + */ +static int tcp_clean_rtx_queue(struct sock *sk, s32 *seq_rtt_p) { struct tcp_sock *tp = tcp_sk(sk); const struct inet_connection_sock *icsk = inet_csk(sk); struct sk_buff *skb; - __u32 now = tcp_time_stamp; + u32 now = tcp_time_stamp; int fully_acked = 1; - int acked = 0; + int flag = 0; int prior_packets = tp->packets_out; - __s32 seq_rtt = -1; + s32 seq_rtt = -1; ktime_t last_ackt = net_invalid_timestamp(); - while ((skb = tcp_write_queue_head(sk)) && - skb != tcp_send_head(sk)) { + while ((skb = tcp_write_queue_head(sk)) && skb != tcp_send_head(sk)) { struct tcp_skb_cb *scb = TCP_SKB_CB(skb); u32 end_seq; u32 packets_acked; - __u8 sacked = scb->sacked; + u8 sacked = scb->sacked; - /* If our packet is before the ack sequence we can - * discard it as it's confirmed to have arrived at - * the other end. - */ if (after(scb->end_seq, tp->snd_una)) { if (tcp_skb_pcount(skb) == 1 || !after(tp->snd_una, scb->seq)) @@ -2598,38 +2592,38 @@ static int tcp_clean_rtx_queue(struct sock *sk, __s32 *seq_rtt_p) * quickly. This is severely frowned upon behavior. */ if (!(scb->flags & TCPCB_FLAG_SYN)) { - acked |= FLAG_DATA_ACKED; + flag |= FLAG_DATA_ACKED; } else { - acked |= FLAG_SYN_ACKED; + flag |= FLAG_SYN_ACKED; tp->retrans_stamp = 0; } /* MTU probing checks */ - if (fully_acked && icsk->icsk_mtup.probe_size) { - if (!after(tp->mtu_probe.probe_seq_end, TCP_SKB_CB(skb)->end_seq)) { - tcp_mtup_probe_success(sk, skb); - } + if (fully_acked && icsk->icsk_mtup.probe_size && + !after(tp->mtu_probe.probe_seq_end, scb->end_seq)) { + tcp_mtup_probe_success(sk, skb); } if (sacked) { if (sacked & TCPCB_RETRANS) { if (sacked & TCPCB_SACKED_RETRANS) tp->retrans_out -= packets_acked; - acked |= FLAG_RETRANS_DATA_ACKED; + flag |= FLAG_RETRANS_DATA_ACKED; seq_rtt = -1; } else if (seq_rtt < 0) { seq_rtt = now - scb->when; if (fully_acked) last_ackt = skb->tstamp; } + if (sacked & TCPCB_SACKED_ACKED) tp->sacked_out -= packets_acked; if (sacked & TCPCB_LOST) tp->lost_out -= packets_acked; - if (sacked & TCPCB_URG) { - if (tp->urg_mode && !before(end_seq, tp->snd_up)) - tp->urg_mode = 0; - } + + if ((sacked & TCPCB_URG) && tp->urg_mode && + !before(end_seq, tp->snd_up)) + tp->urg_mode = 0; } else if (seq_rtt < 0) { seq_rtt = now - scb->when; if (fully_acked) @@ -2645,12 +2639,12 @@ static int tcp_clean_rtx_queue(struct sock *sk, __s32 *seq_rtt_p) tcp_clear_all_retrans_hints(tp); } - if (acked&FLAG_ACKED) { + if (flag & FLAG_ACKED) { u32 pkts_acked = prior_packets - tp->packets_out; const struct tcp_congestion_ops *ca_ops = inet_csk(sk)->icsk_ca_ops; - tcp_ack_update_rtt(sk, acked, seq_rtt); + tcp_ack_update_rtt(sk, flag, seq_rtt); tcp_rearm_rto(sk); tp->fackets_out -= min(pkts_acked, tp->fackets_out); @@ -2664,7 +2658,7 @@ static int tcp_clean_rtx_queue(struct sock *sk, __s32 *seq_rtt_p) s32 rtt_us = -1; /* Is the ACK triggering packet unambiguous? */ - if (!(acked & FLAG_RETRANS_DATA_ACKED)) { + if (!(flag & FLAG_RETRANS_DATA_ACKED)) { /* High resolution needed and available? */ if (ca_ops->flags & TCP_CONG_RTT_STAMP && !ktime_equal(last_ackt, @@ -2703,7 +2697,7 @@ static int tcp_clean_rtx_queue(struct sock *sk, __s32 *seq_rtt_p) } #endif *seq_rtt_p = seq_rtt; - return acked; + return flag; } static void tcp_ack_probe(struct sock *sk)