This change was a followup to the header prediction removal,
so first revert this as a prerequisite to back out hp removal.
Signed-off-by: Florian Westphal <f...@strlen.de>
---
include/net/tcp.h | 5 +++--
net/ipv4/tcp_input.c | 35 +++++++++++++++++++----------------
net/ipv4/tcp_westwood.c | 31 +++++++++++++++++++++++++++----
3 files changed, 49 insertions(+), 22 deletions(-)
diff --git a/include/net/tcp.h b/include/net/tcp.h
index c614ff135b66..c546d13ffbca 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -910,8 +910,9 @@ enum tcp_ca_event {
/* Information about inbound ACK, passed to cong_ops->in_ack_event() */
enum tcp_ca_ack_event_flags {
- CA_ACK_WIN_UPDATE = (1 << 0), /* ACK updated window */
- CA_ACK_ECE = (1 << 1), /* ECE bit is set on ack */
+ CA_ACK_SLOWPATH = (1 << 0), /* In slow path processing */
+ CA_ACK_WIN_UPDATE = (1 << 1), /* ACK updated window */
+ CA_ACK_ECE = (1 << 2), /* ECE bit is set on ack */
};
/*
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 7616cd76f6f6..a0e436366d31 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -3552,7 +3552,6 @@ static int tcp_ack(struct sock *sk, const struct sk_buff
*skb, int flag)
u32 lost = tp->lost;
int acked = 0; /* Number of packets newly acked */
int rexmit = REXMIT_NONE; /* Flag to (re)transmit to recover losses */
- u32 ack_ev_flags = 0;
sack_state.first_sackt = 0;
sack_state.rate = &rs;
@@ -3593,26 +3592,30 @@ static int tcp_ack(struct sock *sk, const struct
sk_buff *skb, int flag)
if (flag & FLAG_UPDATE_TS_RECENT)
tcp_replace_ts_recent(tp, TCP_SKB_CB(skb)->seq);
- if (ack_seq != TCP_SKB_CB(skb)->end_seq)
- flag |= FLAG_DATA;
- else
- NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPPUREACKS);
+ {
+ u32 ack_ev_flags = CA_ACK_SLOWPATH;
- flag |= tcp_ack_update_window(sk, skb, ack, ack_seq);
+ if (ack_seq != TCP_SKB_CB(skb)->end_seq)
+ flag |= FLAG_DATA;
+ else
+ NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPPUREACKS);
- if (TCP_SKB_CB(skb)->sacked)
- flag |= tcp_sacktag_write_queue(sk, skb, prior_snd_una,
- &sack_state);
+ flag |= tcp_ack_update_window(sk, skb, ack, ack_seq);
- if (tcp_ecn_rcv_ecn_echo(tp, tcp_hdr(skb))) {
- flag |= FLAG_ECE;
- ack_ev_flags = CA_ACK_ECE;
- }
+ if (TCP_SKB_CB(skb)->sacked)
+ flag |= tcp_sacktag_write_queue(sk, skb, prior_snd_una,
+ &sack_state);
+
+ if (tcp_ecn_rcv_ecn_echo(tp, tcp_hdr(skb))) {
+ flag |= FLAG_ECE;
+ ack_ev_flags |= CA_ACK_ECE;
+ }
- if (flag & FLAG_WIN_UPDATE)
- ack_ev_flags |= CA_ACK_WIN_UPDATE;
+ if (flag & FLAG_WIN_UPDATE)
+ ack_ev_flags |= CA_ACK_WIN_UPDATE;
- tcp_in_ack_event(sk, ack_ev_flags);
+ tcp_in_ack_event(sk, ack_ev_flags);
+ }
/* We passed data and got it acked, remove any soft error
* log. Something worked...
diff --git a/net/ipv4/tcp_westwood.c b/net/ipv4/tcp_westwood.c
index e5de84310949..bec9cafbe3f9 100644
--- a/net/ipv4/tcp_westwood.c
+++ b/net/ipv4/tcp_westwood.c
@@ -154,6 +154,24 @@ static inline void update_rtt_min(struct westwood *w)
}
/*
+ * @westwood_fast_bw
+ * It is called when we are in fast path. In particular it is called when
+ * header prediction is successful. In such case in fact update is
+ * straight forward and doesn't need any particular care.
+ */
+static inline void westwood_fast_bw(struct sock *sk)
+{
+ const struct tcp_sock *tp = tcp_sk(sk);
+ struct westwood *w = inet_csk_ca(sk);
+
+ westwood_update_window(sk);
+
+ w->bk += tp->snd_una - w->snd_una;
+ w->snd_una = tp->snd_una;
+ update_rtt_min(w);
+}
+
+/*
* @westwood_acked_count
* This function evaluates cumul_ack for evaluating bk in case of
* delayed or partial acks.
@@ -205,12 +223,17 @@ static u32 tcp_westwood_bw_rttmin(const struct sock *sk)
static void tcp_westwood_ack(struct sock *sk, u32 ack_flags)
{
- struct westwood *w = inet_csk_ca(sk);
+ if (ack_flags & CA_ACK_SLOWPATH) {
+ struct westwood *w = inet_csk_ca(sk);
- westwood_update_window(sk);
- w->bk += westwood_acked_count(sk);
+ westwood_update_window(sk);
+ w->bk += westwood_acked_count(sk);
- update_rtt_min(w);
+ update_rtt_min(w);
+ return;
+ }
+
+ westwood_fast_bw(sk);
}
static void tcp_westwood_event(struct sock *sk, enum tcp_ca_event event)
--
2.13.0
