From 31954cd8bb667030b1c0d3d77f28fe71f06999f9 Mon Sep 17 00:00:00 2001 From: Wei Wang Date: Fri, 25 Jan 2019 10:53:19 -0800 Subject: [PATCH] tcp: Refactor pingpong code Instead of using pingpong as a single bit information, we refactor the code to treat it as a counter. When interactive session is detected, we set pingpong count to TCP_PINGPONG_THRESH. And when pingpong count is >= TCP_PINGPONG_THRESH, we consider the session in pingpong mode. This patch is a pure refactor and sets foundation for the next patch. This patch itself does not change any pingpong logic. Signed-off-by: Wei Wang Signed-off-by: Yuchung Cheng Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- include/net/inet_connection_sock.h | 17 +++++++++++++++++ net/dccp/input.c | 2 +- net/dccp/timer.c | 4 ++-- net/ipv4/tcp.c | 10 +++++----- net/ipv4/tcp_input.c | 8 ++++---- net/ipv4/tcp_ipv4.c | 2 +- net/ipv4/tcp_output.c | 4 ++-- net/ipv4/tcp_timer.c | 4 ++-- net/ipv6/tcp_ipv6.c | 2 +- 9 files changed, 35 insertions(+), 18 deletions(-) diff --git a/include/net/inet_connection_sock.h b/include/net/inet_connection_sock.h index fe0d9b4..179609d 100644 --- a/include/net/inet_connection_sock.h +++ b/include/net/inet_connection_sock.h @@ -314,4 +314,21 @@ int inet_csk_compat_setsockopt(struct sock *sk, int level, int optname, char __user *optval, unsigned int optlen); struct dst_entry *inet_csk_update_pmtu(struct sock *sk, u32 mtu); + +#define TCP_PINGPONG_THRESH 1 + +static inline void inet_csk_enter_pingpong_mode(struct sock *sk) +{ + inet_csk(sk)->icsk_ack.pingpong = TCP_PINGPONG_THRESH; +} + +static inline void inet_csk_exit_pingpong_mode(struct sock *sk) +{ + inet_csk(sk)->icsk_ack.pingpong = 0; +} + +static inline bool inet_csk_in_pingpong_mode(struct sock *sk) +{ + return inet_csk(sk)->icsk_ack.pingpong >= TCP_PINGPONG_THRESH; +} #endif /* _INET_CONNECTION_SOCK_H */ diff --git a/net/dccp/input.c b/net/dccp/input.c index 85d6c87..8d03707 100644 --- a/net/dccp/input.c +++ b/net/dccp/input.c @@ -480,7 +480,7 @@ static int dccp_rcv_request_sent_state_process(struct sock *sk, sk_wake_async(sk, SOCK_WAKE_IO, POLL_OUT); } - if (sk->sk_write_pending || icsk->icsk_ack.pingpong || + if (sk->sk_write_pending || inet_csk_in_pingpong_mode(sk) || icsk->icsk_accept_queue.rskq_defer_accept) { /* Save one ACK. Data will be ready after * several ticks, if write_pending is set. diff --git a/net/dccp/timer.c b/net/dccp/timer.c index 1501a20..74e1384 100644 --- a/net/dccp/timer.c +++ b/net/dccp/timer.c @@ -199,7 +199,7 @@ static void dccp_delack_timer(struct timer_list *t) icsk->icsk_ack.pending &= ~ICSK_ACK_TIMER; if (inet_csk_ack_scheduled(sk)) { - if (!icsk->icsk_ack.pingpong) { + if (!inet_csk_in_pingpong_mode(sk)) { /* Delayed ACK missed: inflate ATO. */ icsk->icsk_ack.ato = min(icsk->icsk_ack.ato << 1, icsk->icsk_rto); @@ -207,7 +207,7 @@ static void dccp_delack_timer(struct timer_list *t) /* Delayed ACK missed: leave pingpong mode and * deflate ATO. */ - icsk->icsk_ack.pingpong = 0; + inet_csk_exit_pingpong_mode(sk); icsk->icsk_ack.ato = TCP_ATO_MIN; } dccp_send_ack(sk); diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 12ba214..6f8d292 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -1551,7 +1551,7 @@ static void tcp_cleanup_rbuf(struct sock *sk, int copied) (copied > 0 && ((icsk->icsk_ack.pending & ICSK_ACK_PUSHED2) || ((icsk->icsk_ack.pending & ICSK_ACK_PUSHED) && - !icsk->icsk_ack.pingpong)) && + !inet_csk_in_pingpong_mode(sk))) && !atomic_read(&sk->sk_rmem_alloc))) time_to_ack = true; } @@ -2984,16 +2984,16 @@ static int do_tcp_setsockopt(struct sock *sk, int level, case TCP_QUICKACK: if (!val) { - icsk->icsk_ack.pingpong = 1; + inet_csk_enter_pingpong_mode(sk); } else { - icsk->icsk_ack.pingpong = 0; + inet_csk_exit_pingpong_mode(sk); if ((1 << sk->sk_state) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT) && inet_csk_ack_scheduled(sk)) { icsk->icsk_ack.pending |= ICSK_ACK_PUSHED; tcp_cleanup_rbuf(sk, 1); if (!(val & 1)) - icsk->icsk_ack.pingpong = 1; + inet_csk_enter_pingpong_mode(sk); } } break; @@ -3407,7 +3407,7 @@ static int do_tcp_getsockopt(struct sock *sk, int level, return 0; } case TCP_QUICKACK: - val = !icsk->icsk_ack.pingpong; + val = !inet_csk_in_pingpong_mode(sk); break; case TCP_CONGESTION: diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 76858b1..7a027dec 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -221,7 +221,7 @@ void tcp_enter_quickack_mode(struct sock *sk, unsigned int max_quickacks) struct inet_connection_sock *icsk = inet_csk(sk); tcp_incr_quickack(sk, max_quickacks); - icsk->icsk_ack.pingpong = 0; + inet_csk_exit_pingpong_mode(sk); icsk->icsk_ack.ato = TCP_ATO_MIN; } EXPORT_SYMBOL(tcp_enter_quickack_mode); @@ -236,7 +236,7 @@ static bool tcp_in_quickack_mode(struct sock *sk) const struct dst_entry *dst = __sk_dst_get(sk); return (dst && dst_metric(dst, RTAX_QUICKACK)) || - (icsk->icsk_ack.quick && !icsk->icsk_ack.pingpong); + (icsk->icsk_ack.quick && !inet_csk_in_pingpong_mode(sk)); } static void tcp_ecn_queue_cwr(struct tcp_sock *tp) @@ -4094,7 +4094,7 @@ void tcp_fin(struct sock *sk) case TCP_ESTABLISHED: /* Move to CLOSE_WAIT */ tcp_set_state(sk, TCP_CLOSE_WAIT); - inet_csk(sk)->icsk_ack.pingpong = 1; + inet_csk_enter_pingpong_mode(sk); break; case TCP_CLOSE_WAIT: @@ -5889,7 +5889,7 @@ static int tcp_rcv_synsent_state_process(struct sock *sk, struct sk_buff *skb, return -1; if (sk->sk_write_pending || icsk->icsk_accept_queue.rskq_defer_accept || - icsk->icsk_ack.pingpong) { + inet_csk_in_pingpong_mode(sk)) { /* Save one ACK. Data will be ready after * several ticks, if write_pending is set. * diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index efc6fef..662b034 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -2437,7 +2437,7 @@ static void get_tcp4_sock(struct sock *sk, struct seq_file *f, int i) refcount_read(&sk->sk_refcnt), sk, jiffies_to_clock_t(icsk->icsk_rto), jiffies_to_clock_t(icsk->icsk_ack.ato), - (icsk->icsk_ack.quick << 1) | icsk->icsk_ack.pingpong, + (icsk->icsk_ack.quick << 1) | inet_csk_in_pingpong_mode(sk), tp->snd_cwnd, state == TCP_LISTEN ? fastopenq->max_qlen : diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 26a2948..06228e2 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -171,7 +171,7 @@ static void tcp_event_data_sent(struct tcp_sock *tp, * packet, enter pingpong mode. */ if ((u32)(now - icsk->icsk_ack.lrcvtime) < icsk->icsk_ack.ato) - icsk->icsk_ack.pingpong = 1; + inet_csk_enter_pingpong_mode(sk); } /* Account for an ACK we sent. */ @@ -3569,7 +3569,7 @@ void tcp_send_delayed_ack(struct sock *sk) const struct tcp_sock *tp = tcp_sk(sk); int max_ato = HZ / 2; - if (icsk->icsk_ack.pingpong || + if (inet_csk_in_pingpong_mode(sk) || (icsk->icsk_ack.pending & ICSK_ACK_PUSHED)) max_ato = TCP_DELACK_MAX; diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c index d7399a8..f0c8639 100644 --- a/net/ipv4/tcp_timer.c +++ b/net/ipv4/tcp_timer.c @@ -277,14 +277,14 @@ void tcp_delack_timer_handler(struct sock *sk) icsk->icsk_ack.pending &= ~ICSK_ACK_TIMER; if (inet_csk_ack_scheduled(sk)) { - if (!icsk->icsk_ack.pingpong) { + if (!inet_csk_in_pingpong_mode(sk)) { /* Delayed ACK missed: inflate ATO. */ icsk->icsk_ack.ato = min(icsk->icsk_ack.ato << 1, icsk->icsk_rto); } else { /* Delayed ACK missed: leave pingpong mode and * deflate ATO. */ - icsk->icsk_ack.pingpong = 0; + inet_csk_exit_pingpong_mode(sk); icsk->icsk_ack.ato = TCP_ATO_MIN; } tcp_mstamp_refresh(tcp_sk(sk)); diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index b81eb7c..e51cda7 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -1864,7 +1864,7 @@ static void get_tcp6_sock(struct seq_file *seq, struct sock *sp, int i) refcount_read(&sp->sk_refcnt), sp, jiffies_to_clock_t(icsk->icsk_rto), jiffies_to_clock_t(icsk->icsk_ack.ato), - (icsk->icsk_ack.quick << 1) | icsk->icsk_ack.pingpong, + (icsk->icsk_ack.quick << 1) | inet_csk_in_pingpong_mode(sp), tp->snd_cwnd, state == TCP_LISTEN ? fastopenq->max_qlen : -- 2.7.4