[TCP]: Remove lost_retrans zero seqno special cases
Both high-sack detection and new lowest seq variables have
unnecessary zero special case which are now removed by setting
safe initial seqnos.
This also fixes problem which caused zero received_upto being
passed to tcp_mark_lost_retrans which confused after relations
within the marker loop causing incorrect TCPCB_SACKED_RETRANS
clearing. The problem was noticed because of a performance
report from TAKANO Ryousei <takano@axe-inc.co.jp>.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Acked-by: Ryousei Takano <takano-ryousei@aist.go.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 0f00966..9288220 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -1121,7 +1121,7 @@
struct sk_buff *skb;
int flag = 0;
int cnt = 0;
- u32 new_low_seq = 0;
+ u32 new_low_seq = tp->snd_nxt;
tcp_for_write_queue(skb, sk) {
u32 ack_seq = TCP_SKB_CB(skb)->ack_seq;
@@ -1153,7 +1153,7 @@
NET_INC_STATS_BH(LINUX_MIB_TCPLOSTRETRANSMIT);
}
} else {
- if (!new_low_seq || before(ack_seq, new_low_seq))
+ if (before(ack_seq, new_low_seq))
new_low_seq = ack_seq;
cnt += tcp_skb_pcount(skb);
}
@@ -1242,7 +1242,7 @@
int num_sacks = (ptr[1] - TCPOLEN_SACK_BASE)>>3;
int reord = tp->packets_out;
int prior_fackets;
- u32 highest_sack_end_seq = 0;
+ u32 highest_sack_end_seq = tp->lost_retrans_low;
int flag = 0;
int found_dup_sack = 0;
int cached_fack_count;