On Tue, May 16, 2017 at 5:00 PM, Eric Dumazet <eduma...@google.com> wrote:
> Use tcp_jiffies32 instead of tcp_time_stamp to feed
> tp->snd_cwnd_stamp.
>
> tcp_time_stamp will soon be a litle bit more expensive
> than simply reading 'jiffies'.
>
> Signed-off-by: Eric Dumazet <eduma...@google.com>
Acked-by: Soheil Hassas Yeganeh <soh...@google.com>
> ---
> net/ipv4/tcp_input.c | 14 +++++++-------
> net/ipv4/tcp_metrics.c | 2 +-
> net/ipv4/tcp_output.c | 8 ++++----
> 3 files changed, 12 insertions(+), 12 deletions(-)
>
> diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
> index
> c0b3f909df394214785749704f2760171fe9d160..6a15c9b80b09829799dc37d89ecdbf11ec9ff904
> 100644
> --- a/net/ipv4/tcp_input.c
> +++ b/net/ipv4/tcp_input.c
> @@ -463,7 +463,7 @@ void tcp_init_buffer_space(struct sock *sk)
> tp->window_clamp = max(2 * tp->advmss, maxwin - tp->advmss);
>
> tp->rcv_ssthresh = min(tp->rcv_ssthresh, tp->window_clamp);
> - tp->snd_cwnd_stamp = tcp_time_stamp;
> + tp->snd_cwnd_stamp = tcp_jiffies32;
> }
>
> /* 5. Recalculate window clamp after socket hit its memory bounds. */
> @@ -1954,7 +1954,7 @@ void tcp_enter_loss(struct sock *sk)
> }
> tp->snd_cwnd = 1;
> tp->snd_cwnd_cnt = 0;
> - tp->snd_cwnd_stamp = tcp_time_stamp;
> + tp->snd_cwnd_stamp = tcp_jiffies32;
>
> tp->retrans_out = 0;
> tp->lost_out = 0;
> @@ -2383,7 +2383,7 @@ static void tcp_undo_cwnd_reduction(struct sock *sk,
> bool unmark_loss)
> tcp_ecn_withdraw_cwr(tp);
> }
> }
> - tp->snd_cwnd_stamp = tcp_time_stamp;
> + tp->snd_cwnd_stamp = tcp_jiffies32;
> tp->undo_marker = 0;
> }
>
> @@ -2520,7 +2520,7 @@ static inline void tcp_end_cwnd_reduction(struct sock
> *sk)
> if (inet_csk(sk)->icsk_ca_state == TCP_CA_CWR ||
> (tp->undo_marker && tp->snd_ssthresh < TCP_INFINITE_SSTHRESH)) {
> tp->snd_cwnd = tp->snd_ssthresh;
> - tp->snd_cwnd_stamp = tcp_time_stamp;
> + tp->snd_cwnd_stamp = tcp_jiffies32;
> }
> tcp_ca_event(sk, CA_EVENT_COMPLETE_CWR);
> }
> @@ -2590,7 +2590,7 @@ static void tcp_mtup_probe_success(struct sock *sk)
> tcp_mss_to_mtu(sk, tp->mss_cache) /
> icsk->icsk_mtup.probe_size;
> tp->snd_cwnd_cnt = 0;
> - tp->snd_cwnd_stamp = tcp_time_stamp;
> + tp->snd_cwnd_stamp = tcp_jiffies32;
> tp->snd_ssthresh = tcp_current_ssthresh(sk);
>
> icsk->icsk_mtup.search_low = icsk->icsk_mtup.probe_size;
> @@ -2976,7 +2976,7 @@ static void tcp_cong_avoid(struct sock *sk, u32 ack,
> u32 acked)
> const struct inet_connection_sock *icsk = inet_csk(sk);
>
> icsk->icsk_ca_ops->cong_avoid(sk, ack, acked);
> - tcp_sk(sk)->snd_cwnd_stamp = tcp_time_stamp;
> + tcp_sk(sk)->snd_cwnd_stamp = tcp_jiffies32;
> }
>
> /* Restart timer after forward progress on connection.
> @@ -5019,7 +5019,7 @@ static void tcp_new_space(struct sock *sk)
>
> if (tcp_should_expand_sndbuf(sk)) {
> tcp_sndbuf_expand(sk);
> - tp->snd_cwnd_stamp = tcp_time_stamp;
> + tp->snd_cwnd_stamp = tcp_jiffies32;
> }
>
> sk->sk_write_space(sk);
> diff --git a/net/ipv4/tcp_metrics.c b/net/ipv4/tcp_metrics.c
> index
> 653bbd67e3a39b68d27d26d17571c00ce2854bfd..102b2c90bb807d3a88d31b59324baf72cf901cdf
> 100644
> --- a/net/ipv4/tcp_metrics.c
> +++ b/net/ipv4/tcp_metrics.c
> @@ -524,7 +524,7 @@ void tcp_init_metrics(struct sock *sk)
> tp->snd_cwnd = 1;
> else
> tp->snd_cwnd = tcp_init_cwnd(tp, dst);
> - tp->snd_cwnd_stamp = tcp_time_stamp;
> + tp->snd_cwnd_stamp = tcp_jiffies32;
> }
>
> bool tcp_peer_is_proven(struct request_sock *req, struct dst_entry *dst)
> diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
> index
> be9f8f483e21bdbb4d944fcdae8560f3ae11ee64..4bd50f0b236ba23fe521a76dd9d35ee16acb061f
> 100644
> --- a/net/ipv4/tcp_output.c
> +++ b/net/ipv4/tcp_output.c
> @@ -151,7 +151,7 @@ void tcp_cwnd_restart(struct sock *sk, s32 delta)
> while ((delta -= inet_csk(sk)->icsk_rto) > 0 && cwnd > restart_cwnd)
> cwnd >>= 1;
> tp->snd_cwnd = max(cwnd, restart_cwnd);
> - tp->snd_cwnd_stamp = tcp_time_stamp;
> + tp->snd_cwnd_stamp = tcp_jiffies32;
> tp->snd_cwnd_used = 0;
> }
>
> @@ -1576,7 +1576,7 @@ static void tcp_cwnd_application_limited(struct sock
> *sk)
> }
> tp->snd_cwnd_used = 0;
> }
> - tp->snd_cwnd_stamp = tcp_time_stamp;
> + tp->snd_cwnd_stamp = tcp_jiffies32;
> }
>
> static void tcp_cwnd_validate(struct sock *sk, bool is_cwnd_limited)
> @@ -1597,14 +1597,14 @@ static void tcp_cwnd_validate(struct sock *sk, bool
> is_cwnd_limited)
> if (tcp_is_cwnd_limited(sk)) {
> /* Network is feed fully. */
> tp->snd_cwnd_used = 0;
> - tp->snd_cwnd_stamp = tcp_time_stamp;
> + tp->snd_cwnd_stamp = tcp_jiffies32;
> } else {
> /* Network starves. */
> if (tp->packets_out > tp->snd_cwnd_used)
> tp->snd_cwnd_used = tp->packets_out;
>
> if (sysctl_tcp_slow_start_after_idle &&
> - (s32)(tcp_time_stamp - tp->snd_cwnd_stamp) >=
> inet_csk(sk)->icsk_rto &&
> + (s32)(tcp_jiffies32 - tp->snd_cwnd_stamp) >=
> inet_csk(sk)->icsk_rto &&
> !ca_ops->cong_control)
> tcp_cwnd_application_limited(sk);
>
> --
> 2.13.0.303.g4ebf302169-goog
>
