From 6514890f7aa8dd75fa46e282a1c7a8615e86f363 Mon Sep 17 00:00:00 2001 From: Neal Cardwell Date: Fri, 20 Feb 2015 13:33:16 -0500 Subject: tcp: fix tcp_should_expand_sndbuf() to use tcp_packets_in_flight() tcp_should_expand_sndbuf() does not expand the send buffer if we have filled the congestion window. However, it should use tcp_packets_in_flight() instead of tp->packets_out to make this check. Testing has established that the difference matters a lot if there are many SACKed packets, causing a needless performance shortfall. Signed-off-by: Neal Cardwell Signed-off-by: Yuchung Cheng Signed-off-by: Eric Dumazet Signed-off-by: Nandita Dukkipati Signed-off-by: David S. Miller --- net/ipv4/tcp_input.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/ipv4/tcp_input.c') diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 8fdd27b17306..fb4cf8b8e121 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -4770,7 +4770,7 @@ static bool tcp_should_expand_sndbuf(const struct sock *sk) return false; /* If we filled the congestion window, do not expand. */ - if (tp->packets_out >= tp->snd_cwnd) + if (tcp_packets_in_flight(tp) >= tp->snd_cwnd) return false; return true; -- cgit v1.2.3 From 666b805150efd62f05810ff0db08f44a2370c937 Mon Sep 17 00:00:00 2001 From: Neal Cardwell Date: Wed, 1 Apr 2015 20:26:46 -0400 Subject: tcp: fix FRTO undo on cumulative ACK of SACKed range On processing cumulative ACKs, the FRTO code was not checking the SACKed bit, meaning that there could be a spurious FRTO undo on a cumulative ACK of a previously SACKed skb. The FRTO code should only consider a cumulative ACK to indicate that an original/unretransmitted skb is newly ACKed if the skb was not yet SACKed. The effect of the spurious FRTO undo would typically be to make the connection think that all previously-sent packets were in flight when they really weren't, leading to a stall and an RTO. Signed-off-by: Neal Cardwell Signed-off-by: Yuchung Cheng Fixes: e33099f96d99c ("tcp: implement RFC5682 F-RTO") Signed-off-by: David S. Miller --- net/ipv4/tcp_input.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'net/ipv4/tcp_input.c') diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index fb4cf8b8e121..f501ac048366 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -3105,10 +3105,11 @@ static int tcp_clean_rtx_queue(struct sock *sk, int prior_fackets, if (!first_ackt.v64) first_ackt = last_ackt; - if (!(sacked & TCPCB_SACKED_ACKED)) + if (!(sacked & TCPCB_SACKED_ACKED)) { reord = min(pkts_acked, reord); - if (!after(scb->end_seq, tp->high_seq)) - flag |= FLAG_ORIG_SACK_ACKED; + if (!after(scb->end_seq, tp->high_seq)) + flag |= FLAG_ORIG_SACK_ACKED; + } } if (sacked & TCPCB_SACKED_ACKED) -- cgit v1.2.3