[PATCH net-next 2/2] tcp: add related fields into SCM_TIMESTAMPING_OPT_STATS

[Wei Wang]

From: Wei Wang <wei...@google.com>

Add the following stats into SCM_TIMESTAMPING_OPT_STATS control msg:
    TCP_NLA_PACING_RATE
    TCP_NLA_DELIVERY_RATE
    TCP_NLA_SND_CWND
    TCP_NLA_REORDERING
    TCP_NLA_MIN_RTT
    TCP_NLA_RECUR_RETRANS
    TCP_NLA_DELIVERY_RATE_APP_LMT

Signed-off-by: Wei Wang <wei...@google.com>
Acked-by: Yuchung Cheng <ych...@google.com>
Acked-by: Soheil Hassas Yeganeh <soh...@google.com>
---
 include/uapi/linux/tcp.h |  8 ++++++++
 net/ipv4/tcp.c           | 20 +++++++++++++++++++-
 2 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/include/uapi/linux/tcp.h b/include/uapi/linux/tcp.h
index a5507c977497..030e594bab45 100644
--- a/include/uapi/linux/tcp.h
+++ b/include/uapi/linux/tcp.h
@@ -231,6 +231,14 @@ enum {
        TCP_NLA_SNDBUF_LIMITED, /* Time (usec) limited by send buffer */
        TCP_NLA_DATA_SEGS_OUT,  /* Data pkts sent including retransmission */
        TCP_NLA_TOTAL_RETRANS,  /* Data pkts retransmitted */
+       TCP_NLA_PACING_RATE,    /* Pacing rate in bytes per second */
+       TCP_NLA_DELIVERY_RATE,  /* Delivery rate in bytes per second */
+       TCP_NLA_SND_CWND,       /* Sending congestion window */
+       TCP_NLA_REORDERING,     /* Reordering metric */
+       TCP_NLA_MIN_RTT,        /* minimum RTT */
+       TCP_NLA_RECUR_RETRANS,  /* Recurring retransmits for the current pkt */
+       TCP_NLA_DELIVERY_RATE_APP_LMT, /* delivery rate application limited ? */
+
 };
 
 /* for TCP_MD5SIG socket option */
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 65d210d0394c..be78662faa1a 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -2947,8 +2947,12 @@ struct sk_buff *tcp_get_timestamping_opt_stats(const 
struct sock *sk)
        const struct tcp_sock *tp = tcp_sk(sk);
        struct sk_buff *stats;
        struct tcp_info info;
+       u64 rate64;
+       u32 rate;
 
-       stats = alloc_skb(5 * nla_total_size_64bit(sizeof(u64)), GFP_ATOMIC);
+       stats = alloc_skb(7 * nla_total_size_64bit(sizeof(u64)) +
+                         3 * nla_total_size(sizeof(u32)) +
+                         2 * nla_total_size(sizeof(u8)), GFP_ATOMIC);
        if (!stats)
                return NULL;
 
@@ -2963,6 +2967,20 @@ struct sk_buff *tcp_get_timestamping_opt_stats(const 
struct sock *sk)
                          tp->data_segs_out, TCP_NLA_PAD);
        nla_put_u64_64bit(stats, TCP_NLA_TOTAL_RETRANS,
                          tp->total_retrans, TCP_NLA_PAD);
+
+       rate = READ_ONCE(sk->sk_pacing_rate);
+       rate64 = rate != ~0U ? rate : ~0ULL;
+       nla_put_u64_64bit(stats, TCP_NLA_PACING_RATE, rate64, TCP_NLA_PAD);
+
+       rate64 = tcp_compute_delivery_rate(tp);
+       nla_put_u64_64bit(stats, TCP_NLA_DELIVERY_RATE, rate64, TCP_NLA_PAD);
+
+       nla_put_u32(stats, TCP_NLA_SND_CWND, tp->snd_cwnd);
+       nla_put_u32(stats, TCP_NLA_REORDERING, tp->reordering);
+       nla_put_u32(stats, TCP_NLA_MIN_RTT, tcp_min_rtt(tp));
+
+       nla_put_u8(stats, TCP_NLA_RECUR_RETRANS, 
inet_csk(sk)->icsk_retransmits);
+       nla_put_u8(stats, TCP_NLA_DELIVERY_RATE_APP_LMT, 
!!tp->rate_app_limited);
        return stats;
 }
 
-- 
2.14.0.rc0.400.g1c36432dff-goog