// SPDX-License-Identifier: GPL-2.0 /* Refer to samples/bpf/tcp_bpf.readme for the instructions on * how to run this sample program. */ #include <linux/bpf.h> #include "bpf_helpers.h" #include "bpf_endian.h" #define INTERVAL 1000000000ULL int _version SEC("version") = 1; char _license[] SEC("license") = "GPL"; struct { __u32 type; __u32 map_flags; int *key; __u64 *value; } bpf_next_dump SEC(".maps") = { .type = BPF_MAP_TYPE_SK_STORAGE, .map_flags = BPF_F_NO_PREALLOC, }; SEC("sockops") int _sockops(struct bpf_sock_ops *ctx) { struct bpf_tcp_sock *tcp_sk; struct bpf_sock *sk; __u64 *next_dump; __u64 now; switch (ctx->op) { case BPF_SOCK_OPS_TCP_CONNECT_CB: bpf_sock_ops_cb_flags_set(ctx, BPF_SOCK_OPS_RTT_CB_FLAG); return 1; case BPF_SOCK_OPS_RTT_CB: break; default: return 1; } sk = ctx->sk; if (!sk) return 1; next_dump = bpf_sk_storage_get(&bpf_next_dump, sk, 0, BPF_SK_STORAGE_GET_F_CREATE); if (!next_dump) return 1; now = bpf_ktime_get_ns(); if (now < *next_dump) return 1; tcp_sk = bpf_tcp_sock(sk); if (!tcp_sk) return 1; *next_dump = now + INTERVAL; bpf_printk("dsack_dups=%u delivered=%u\n", tcp_sk->dsack_dups, tcp_sk->delivered); bpf_printk("delivered_ce=%u icsk_retransmits=%u\n", tcp_sk->delivered_ce, tcp_sk->icsk_retransmits); return 1; }