1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun /* Refer to samples/bpf/tcp_bpf.readme for the instructions on
3*4882a593Smuzhiyun * how to run this sample program.
4*4882a593Smuzhiyun */
5*4882a593Smuzhiyun #include <linux/bpf.h>
6*4882a593Smuzhiyun
7*4882a593Smuzhiyun #include <bpf/bpf_helpers.h>
8*4882a593Smuzhiyun #include <bpf/bpf_endian.h>
9*4882a593Smuzhiyun
10*4882a593Smuzhiyun #define INTERVAL 1000000000ULL
11*4882a593Smuzhiyun
12*4882a593Smuzhiyun int _version SEC("version") = 1;
13*4882a593Smuzhiyun char _license[] SEC("license") = "GPL";
14*4882a593Smuzhiyun
15*4882a593Smuzhiyun struct {
16*4882a593Smuzhiyun __u32 type;
17*4882a593Smuzhiyun __u32 map_flags;
18*4882a593Smuzhiyun int *key;
19*4882a593Smuzhiyun __u64 *value;
20*4882a593Smuzhiyun } bpf_next_dump SEC(".maps") = {
21*4882a593Smuzhiyun .type = BPF_MAP_TYPE_SK_STORAGE,
22*4882a593Smuzhiyun .map_flags = BPF_F_NO_PREALLOC,
23*4882a593Smuzhiyun };
24*4882a593Smuzhiyun
25*4882a593Smuzhiyun SEC("sockops")
_sockops(struct bpf_sock_ops * ctx)26*4882a593Smuzhiyun int _sockops(struct bpf_sock_ops *ctx)
27*4882a593Smuzhiyun {
28*4882a593Smuzhiyun struct bpf_tcp_sock *tcp_sk;
29*4882a593Smuzhiyun struct bpf_sock *sk;
30*4882a593Smuzhiyun __u64 *next_dump;
31*4882a593Smuzhiyun __u64 now;
32*4882a593Smuzhiyun
33*4882a593Smuzhiyun switch (ctx->op) {
34*4882a593Smuzhiyun case BPF_SOCK_OPS_TCP_CONNECT_CB:
35*4882a593Smuzhiyun bpf_sock_ops_cb_flags_set(ctx, BPF_SOCK_OPS_RTT_CB_FLAG);
36*4882a593Smuzhiyun return 1;
37*4882a593Smuzhiyun case BPF_SOCK_OPS_RTT_CB:
38*4882a593Smuzhiyun break;
39*4882a593Smuzhiyun default:
40*4882a593Smuzhiyun return 1;
41*4882a593Smuzhiyun }
42*4882a593Smuzhiyun
43*4882a593Smuzhiyun sk = ctx->sk;
44*4882a593Smuzhiyun if (!sk)
45*4882a593Smuzhiyun return 1;
46*4882a593Smuzhiyun
47*4882a593Smuzhiyun next_dump = bpf_sk_storage_get(&bpf_next_dump, sk, 0,
48*4882a593Smuzhiyun BPF_SK_STORAGE_GET_F_CREATE);
49*4882a593Smuzhiyun if (!next_dump)
50*4882a593Smuzhiyun return 1;
51*4882a593Smuzhiyun
52*4882a593Smuzhiyun now = bpf_ktime_get_ns();
53*4882a593Smuzhiyun if (now < *next_dump)
54*4882a593Smuzhiyun return 1;
55*4882a593Smuzhiyun
56*4882a593Smuzhiyun tcp_sk = bpf_tcp_sock(sk);
57*4882a593Smuzhiyun if (!tcp_sk)
58*4882a593Smuzhiyun return 1;
59*4882a593Smuzhiyun
60*4882a593Smuzhiyun *next_dump = now + INTERVAL;
61*4882a593Smuzhiyun
62*4882a593Smuzhiyun bpf_printk("dsack_dups=%u delivered=%u\n",
63*4882a593Smuzhiyun tcp_sk->dsack_dups, tcp_sk->delivered);
64*4882a593Smuzhiyun bpf_printk("delivered_ce=%u icsk_retransmits=%u\n",
65*4882a593Smuzhiyun tcp_sk->delivered_ce, tcp_sk->icsk_retransmits);
66*4882a593Smuzhiyun
67*4882a593Smuzhiyun return 1;
68*4882a593Smuzhiyun }
69