1// SPDX-License-Identifier: GPL-2.0
 2
 3#include "bpf_tracing_net.h"
 
 4#include <bpf/bpf_helpers.h>
 5#include <bpf/bpf_tracing.h>
 6
 7char _license[] SEC("license") = "GPL";
 8
 9#define USEC_PER_SEC 1000000UL
10
11#define min(a, b) ((a) < (b) ? (a) : (b))
12
13static unsigned int tcp_left_out(const struct tcp_sock *tp)
 
 
 
 
 
14{
15	return tp->sacked_out + tp->lost_out;
16}
17
18static unsigned int tcp_packets_in_flight(const struct tcp_sock *tp)
19{
20	return tp->packets_out - tcp_left_out(tp) + tp->retrans_out;
21}
22
23SEC("struct_ops")
24void BPF_PROG(write_sk_pacing_init, struct sock *sk)
25{
26#ifdef ENABLE_ATOMICS_TESTS
27	__sync_bool_compare_and_swap(&sk->sk_pacing_status, SK_PACING_NONE,
28				     SK_PACING_NEEDED);
29#else
30	sk->sk_pacing_status = SK_PACING_NEEDED;
31#endif
32}
33
34SEC("struct_ops")
35void BPF_PROG(write_sk_pacing_cong_control, struct sock *sk,
36	      const struct rate_sample *rs)
37{
38	struct tcp_sock *tp = tcp_sk(sk);
39	unsigned long rate =
40		((tp->snd_cwnd * tp->mss_cache * USEC_PER_SEC) << 3) /
41		(tp->srtt_us ?: 1U << 3);
42	sk->sk_pacing_rate = min(rate, sk->sk_max_pacing_rate);
43	tp->app_limited = (tp->delivered + tcp_packets_in_flight(tp)) ?: 1;
44}
45
46SEC("struct_ops")
47__u32 BPF_PROG(write_sk_pacing_ssthresh, struct sock *sk)
48{
49	return tcp_sk(sk)->snd_ssthresh;
50}
51
52SEC("struct_ops")
53__u32 BPF_PROG(write_sk_pacing_undo_cwnd, struct sock *sk)
54{
55	return tcp_sk(sk)->snd_cwnd;
56}
57
58SEC(".struct_ops")
59struct tcp_congestion_ops write_sk_pacing = {
60	.init = (void *)write_sk_pacing_init,
61	.cong_control = (void *)write_sk_pacing_cong_control,
62	.ssthresh = (void *)write_sk_pacing_ssthresh,
63	.undo_cwnd = (void *)write_sk_pacing_undo_cwnd,
64	.name = "bpf_w_sk_pacing",
65};

 1// SPDX-License-Identifier: GPL-2.0
 2
 3#include "vmlinux.h"
 4
 5#include <bpf/bpf_helpers.h>
 6#include <bpf/bpf_tracing.h>
 7
 8char _license[] SEC("license") = "GPL";
 9
10#define USEC_PER_SEC 1000000UL
11
12#define min(a, b) ((a) < (b) ? (a) : (b))
13
14static inline struct tcp_sock *tcp_sk(const struct sock *sk)
15{
16	return (struct tcp_sock *)sk;
17}
18
19static inline unsigned int tcp_left_out(const struct tcp_sock *tp)
20{
21	return tp->sacked_out + tp->lost_out;
22}
23
24static inline unsigned int tcp_packets_in_flight(const struct tcp_sock *tp)
25{
26	return tp->packets_out - tcp_left_out(tp) + tp->retrans_out;
27}
28
29SEC("struct_ops/write_sk_pacing_init")
30void BPF_PROG(write_sk_pacing_init, struct sock *sk)
31{
32#ifdef ENABLE_ATOMICS_TESTS
33	__sync_bool_compare_and_swap(&sk->sk_pacing_status, SK_PACING_NONE,
34				     SK_PACING_NEEDED);
35#else
36	sk->sk_pacing_status = SK_PACING_NEEDED;
37#endif
38}
39
40SEC("struct_ops/write_sk_pacing_cong_control")
41void BPF_PROG(write_sk_pacing_cong_control, struct sock *sk,
42	      const struct rate_sample *rs)
43{
44	struct tcp_sock *tp = tcp_sk(sk);
45	unsigned long rate =
46		((tp->snd_cwnd * tp->mss_cache * USEC_PER_SEC) << 3) /
47		(tp->srtt_us ?: 1U << 3);
48	sk->sk_pacing_rate = min(rate, sk->sk_max_pacing_rate);
49	tp->app_limited = (tp->delivered + tcp_packets_in_flight(tp)) ?: 1;
50}
51
52SEC("struct_ops/write_sk_pacing_ssthresh")
53__u32 BPF_PROG(write_sk_pacing_ssthresh, struct sock *sk)
54{
55	return tcp_sk(sk)->snd_ssthresh;
56}
57
58SEC("struct_ops/write_sk_pacing_undo_cwnd")
59__u32 BPF_PROG(write_sk_pacing_undo_cwnd, struct sock *sk)
60{
61	return tcp_sk(sk)->snd_cwnd;
62}
63
64SEC(".struct_ops")
65struct tcp_congestion_ops write_sk_pacing = {
66	.init = (void *)write_sk_pacing_init,
67	.cong_control = (void *)write_sk_pacing_cong_control,
68	.ssthresh = (void *)write_sk_pacing_ssthresh,
69	.undo_cwnd = (void *)write_sk_pacing_undo_cwnd,
70	.name = "bpf_w_sk_pacing",
71};