1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/bpf.h> 3 #include "bpf_helpers.h" 4 5 char _license[] SEC("license") = "GPL"; 6 __u32 _version SEC("version") = 1; 7 8 struct tcp_rtt_storage { 9 __u32 invoked; 10 __u32 dsack_dups; 11 __u32 delivered; 12 __u32 delivered_ce; 13 __u32 icsk_retransmits; 14 }; 15 16 struct bpf_map_def SEC("maps") socket_storage_map = { 17 .type = BPF_MAP_TYPE_SK_STORAGE, 18 .key_size = sizeof(int), 19 .value_size = sizeof(struct tcp_rtt_storage), 20 .map_flags = BPF_F_NO_PREALLOC, 21 }; 22 BPF_ANNOTATE_KV_PAIR(socket_storage_map, int, struct tcp_rtt_storage); 23 24 SEC("sockops") 25 int _sockops(struct bpf_sock_ops *ctx) 26 { 27 struct tcp_rtt_storage *storage; 28 struct bpf_tcp_sock *tcp_sk; 29 int op = (int) ctx->op; 30 struct bpf_sock *sk; 31 32 sk = ctx->sk; 33 if (!sk) 34 return 1; 35 36 storage = bpf_sk_storage_get(&socket_storage_map, sk, 0, 37 BPF_SK_STORAGE_GET_F_CREATE); 38 if (!storage) 39 return 1; 40 41 if (op == BPF_SOCK_OPS_TCP_CONNECT_CB) { 42 bpf_sock_ops_cb_flags_set(ctx, BPF_SOCK_OPS_RTT_CB_FLAG); 43 return 1; 44 } 45 46 if (op != BPF_SOCK_OPS_RTT_CB) 47 return 1; 48 49 tcp_sk = bpf_tcp_sock(sk); 50 if (!tcp_sk) 51 return 1; 52 53 storage->invoked++; 54 55 storage->dsack_dups = tcp_sk->dsack_dups; 56 storage->delivered = tcp_sk->delivered; 57 storage->delivered_ce = tcp_sk->delivered_ce; 58 storage->icsk_retransmits = tcp_sk->icsk_retransmits; 59 60 return 1; 61 } 62