diff options
| -rw-r--r-- | net/ipv4/tcp_westwood.c | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/net/ipv4/tcp_westwood.c b/net/ipv4/tcp_westwood.c index edf2ee19a8ba..4247da1384bf 100644 --- a/net/ipv4/tcp_westwood.c +++ b/net/ipv4/tcp_westwood.c @@ -40,6 +40,7 @@ struct westwood { u32 rtt; u32 rtt_min; /* minimum observed RTT */ u8 first_ack; /* flag which infers that this is the first ack */ + u8 reset_rtt_min; /* Reset RTT min to next RTT sample*/ }; @@ -67,6 +68,7 @@ static void tcp_westwood_init(struct sock *sk) w->bw_est = 0; w->accounted = 0; w->cumul_ack = 0; + w->reset_rtt_min = 1; w->rtt_min = w->rtt = TCP_WESTWOOD_INIT_RTT; w->rtt_win_sx = tcp_time_stamp; w->snd_una = tcp_sk(sk)->snd_una; @@ -142,6 +144,16 @@ static void westwood_update_window(struct sock *sk) } } +static inline void update_rtt_min(struct westwood *w) +{ + if (w->reset_rtt_min) { + w->rtt_min = w->rtt; + w->reset_rtt_min = 0; + } else + w->rtt_min = min(w->rtt, w->rtt_min); +} + + /* * @westwood_fast_bw * It is called when we are in fast path. In particular it is called when @@ -157,7 +169,7 @@ static inline void westwood_fast_bw(struct sock *sk) w->bk += tp->snd_una - w->snd_una; w->snd_una = tp->snd_una; - w->rtt_min = min(w->rtt, w->rtt_min); + update_rtt_min(w); } /* @@ -226,12 +238,14 @@ static void tcp_westwood_event(struct sock *sk, enum tcp_ca_event event) case CA_EVENT_FRTO: tp->snd_ssthresh = tcp_westwood_bw_rttmin(sk); + /* Update RTT_min when next ack arrives */ + w->reset_rtt_min = 1; break; case CA_EVENT_SLOW_ACK: westwood_update_window(sk); w->bk += westwood_acked_count(sk); - w->rtt_min = min(w->rtt, w->rtt_min); + update_rtt_min(w); break; default: |