bpf: Add bpf_dctcp example
This patch adds a bpf_dctcp example. It currently does not do no-ECN fallback but the same could be done through the cgrp2-bpf. Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200109003517.3856825-1-kafai@fb.comalistair/sensors
Martin KaFai Lau
Alexei Starovoitov
parent
590a008882
commit
09903869f6
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@ -0,0 +1,228 @@
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/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef __BPF_TCP_HELPERS_H
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#define __BPF_TCP_HELPERS_H
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#include <stdbool.h>
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#include <linux/types.h>
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#include <bpf_helpers.h>
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#include <bpf_core_read.h>
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#include "bpf_trace_helpers.h"
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/* "struct_ops/" is only a convention. not a requirement. */
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#define BPF_TCP_OPS_0(fname, ret_type, ...) BPF_TRACE_x(0, "struct_ops/"#fname, fname, ret_type, __VA_ARGS__)
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#define BPF_TCP_OPS_1(fname, ret_type, ...) BPF_TRACE_x(1, "struct_ops/"#fname, fname, ret_type, __VA_ARGS__)
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#define BPF_TCP_OPS_2(fname, ret_type, ...) BPF_TRACE_x(2, "struct_ops/"#fname, fname, ret_type, __VA_ARGS__)
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#define BPF_TCP_OPS_3(fname, ret_type, ...) BPF_TRACE_x(3, "struct_ops/"#fname, fname, ret_type, __VA_ARGS__)
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#define BPF_TCP_OPS_4(fname, ret_type, ...) BPF_TRACE_x(4, "struct_ops/"#fname, fname, ret_type, __VA_ARGS__)
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#define BPF_TCP_OPS_5(fname, ret_type, ...) BPF_TRACE_x(5, "struct_ops/"#fname, fname, ret_type, __VA_ARGS__)
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struct sock_common {
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unsigned char skc_state;
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} __attribute__((preserve_access_index));
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struct sock {
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struct sock_common __sk_common;
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} __attribute__((preserve_access_index));
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struct inet_sock {
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struct sock sk;
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} __attribute__((preserve_access_index));
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struct inet_connection_sock {
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struct inet_sock icsk_inet;
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__u8 icsk_ca_state:6,
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icsk_ca_setsockopt:1,
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icsk_ca_dst_locked:1;
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struct {
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__u8 pending;
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} icsk_ack;
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__u64 icsk_ca_priv[104 / sizeof(__u64)];
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} __attribute__((preserve_access_index));
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struct tcp_sock {
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struct inet_connection_sock inet_conn;
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__u32 rcv_nxt;
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__u32 snd_nxt;
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__u32 snd_una;
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__u8 ecn_flags;
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__u32 delivered;
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__u32 delivered_ce;
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__u32 snd_cwnd;
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__u32 snd_cwnd_cnt;
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__u32 snd_cwnd_clamp;
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__u32 snd_ssthresh;
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__u8 syn_data:1, /* SYN includes data */
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syn_fastopen:1, /* SYN includes Fast Open option */
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syn_fastopen_exp:1,/* SYN includes Fast Open exp. option */
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syn_fastopen_ch:1, /* Active TFO re-enabling probe */
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syn_data_acked:1,/* data in SYN is acked by SYN-ACK */
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save_syn:1, /* Save headers of SYN packet */
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is_cwnd_limited:1,/* forward progress limited by snd_cwnd? */
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syn_smc:1; /* SYN includes SMC */
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__u32 max_packets_out;
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__u32 lsndtime;
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__u32 prior_cwnd;
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} __attribute__((preserve_access_index));
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static __always_inline struct inet_connection_sock *inet_csk(const struct sock *sk)
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{
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return (struct inet_connection_sock *)sk;
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}
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static __always_inline void *inet_csk_ca(const struct sock *sk)
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{
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return (void *)inet_csk(sk)->icsk_ca_priv;
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}
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static __always_inline struct tcp_sock *tcp_sk(const struct sock *sk)
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{
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return (struct tcp_sock *)sk;
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}
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static __always_inline bool before(__u32 seq1, __u32 seq2)
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{
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return (__s32)(seq1-seq2) < 0;
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}
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#define after(seq2, seq1) before(seq1, seq2)
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#define TCP_ECN_OK 1
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#define TCP_ECN_QUEUE_CWR 2
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#define TCP_ECN_DEMAND_CWR 4
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#define TCP_ECN_SEEN 8
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enum inet_csk_ack_state_t {
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ICSK_ACK_SCHED = 1,
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ICSK_ACK_TIMER = 2,
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ICSK_ACK_PUSHED = 4,
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ICSK_ACK_PUSHED2 = 8,
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ICSK_ACK_NOW = 16 /* Send the next ACK immediately (once) */
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};
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enum tcp_ca_event {
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CA_EVENT_TX_START = 0,
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CA_EVENT_CWND_RESTART = 1,
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CA_EVENT_COMPLETE_CWR = 2,
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CA_EVENT_LOSS = 3,
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CA_EVENT_ECN_NO_CE = 4,
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CA_EVENT_ECN_IS_CE = 5,
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};
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enum tcp_ca_state {
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TCP_CA_Open = 0,
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TCP_CA_Disorder = 1,
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TCP_CA_CWR = 2,
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TCP_CA_Recovery = 3,
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TCP_CA_Loss = 4
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};
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struct ack_sample {
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__u32 pkts_acked;
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__s32 rtt_us;
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__u32 in_flight;
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} __attribute__((preserve_access_index));
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struct rate_sample {
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__u64 prior_mstamp; /* starting timestamp for interval */
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__u32 prior_delivered; /* tp->delivered at "prior_mstamp" */
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__s32 delivered; /* number of packets delivered over interval */
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long interval_us; /* time for tp->delivered to incr "delivered" */
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__u32 snd_interval_us; /* snd interval for delivered packets */
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__u32 rcv_interval_us; /* rcv interval for delivered packets */
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long rtt_us; /* RTT of last (S)ACKed packet (or -1) */
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int losses; /* number of packets marked lost upon ACK */
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__u32 acked_sacked; /* number of packets newly (S)ACKed upon ACK */
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__u32 prior_in_flight; /* in flight before this ACK */
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bool is_app_limited; /* is sample from packet with bubble in pipe? */
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bool is_retrans; /* is sample from retransmission? */
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bool is_ack_delayed; /* is this (likely) a delayed ACK? */
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} __attribute__((preserve_access_index));
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#define TCP_CA_NAME_MAX 16
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#define TCP_CONG_NEEDS_ECN 0x2
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struct tcp_congestion_ops {
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char name[TCP_CA_NAME_MAX];
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__u32 flags;
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/* initialize private data (optional) */
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void (*init)(struct sock *sk);
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/* cleanup private data (optional) */
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void (*release)(struct sock *sk);
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/* return slow start threshold (required) */
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__u32 (*ssthresh)(struct sock *sk);
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/* do new cwnd calculation (required) */
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void (*cong_avoid)(struct sock *sk, __u32 ack, __u32 acked);
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/* call before changing ca_state (optional) */
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void (*set_state)(struct sock *sk, __u8 new_state);
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/* call when cwnd event occurs (optional) */
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void (*cwnd_event)(struct sock *sk, enum tcp_ca_event ev);
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/* call when ack arrives (optional) */
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void (*in_ack_event)(struct sock *sk, __u32 flags);
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/* new value of cwnd after loss (required) */
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__u32 (*undo_cwnd)(struct sock *sk);
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/* hook for packet ack accounting (optional) */
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void (*pkts_acked)(struct sock *sk, const struct ack_sample *sample);
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/* override sysctl_tcp_min_tso_segs */
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__u32 (*min_tso_segs)(struct sock *sk);
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/* returns the multiplier used in tcp_sndbuf_expand (optional) */
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__u32 (*sndbuf_expand)(struct sock *sk);
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/* call when packets are delivered to update cwnd and pacing rate,
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* after all the ca_state processing. (optional)
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*/
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void (*cong_control)(struct sock *sk, const struct rate_sample *rs);
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};
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#define min(a, b) ((a) < (b) ? (a) : (b))
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#define max(a, b) ((a) > (b) ? (a) : (b))
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#define min_not_zero(x, y) ({ \
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typeof(x) __x = (x); \
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typeof(y) __y = (y); \
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__x == 0 ? __y : ((__y == 0) ? __x : min(__x, __y)); })
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static __always_inline __u32 tcp_slow_start(struct tcp_sock *tp, __u32 acked)
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{
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__u32 cwnd = min(tp->snd_cwnd + acked, tp->snd_ssthresh);
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acked -= cwnd - tp->snd_cwnd;
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tp->snd_cwnd = min(cwnd, tp->snd_cwnd_clamp);
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return acked;
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}
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static __always_inline bool tcp_in_slow_start(const struct tcp_sock *tp)
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{
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return tp->snd_cwnd < tp->snd_ssthresh;
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}
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static __always_inline bool tcp_is_cwnd_limited(const struct sock *sk)
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{
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const struct tcp_sock *tp = tcp_sk(sk);
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/* If in slow start, ensure cwnd grows to twice what was ACKed. */
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if (tcp_in_slow_start(tp))
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return tp->snd_cwnd < 2 * tp->max_packets_out;
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return !!BPF_CORE_READ_BITFIELD(tp, is_cwnd_limited);
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}
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static __always_inline void tcp_cong_avoid_ai(struct tcp_sock *tp, __u32 w, __u32 acked)
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{
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/* If credits accumulated at a higher w, apply them gently now. */
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if (tp->snd_cwnd_cnt >= w) {
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tp->snd_cwnd_cnt = 0;
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tp->snd_cwnd++;
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}
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tp->snd_cwnd_cnt += acked;
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if (tp->snd_cwnd_cnt >= w) {
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__u32 delta = tp->snd_cwnd_cnt / w;
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tp->snd_cwnd_cnt -= delta * w;
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tp->snd_cwnd += delta;
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}
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tp->snd_cwnd = min(tp->snd_cwnd, tp->snd_cwnd_clamp);
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}
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#endif
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@ -0,0 +1,187 @@
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// SPDX-License-Identifier: GPL-2.0
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/* Copyright (c) 2019 Facebook */
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#include <linux/err.h>
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#include <test_progs.h>
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#include "bpf_dctcp.skel.h"
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#define min(a, b) ((a) < (b) ? (a) : (b))
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static const unsigned int total_bytes = 10 * 1024 * 1024;
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static const struct timeval timeo_sec = { .tv_sec = 10 };
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static const size_t timeo_optlen = sizeof(timeo_sec);
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static int stop, duration;
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static int settimeo(int fd)
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{
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int err;
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err = setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, &timeo_sec,
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timeo_optlen);
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if (CHECK(err == -1, "setsockopt(fd, SO_RCVTIMEO)", "errno:%d\n",
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errno))
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return -1;
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err = setsockopt(fd, SOL_SOCKET, SO_SNDTIMEO, &timeo_sec,
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timeo_optlen);
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if (CHECK(err == -1, "setsockopt(fd, SO_SNDTIMEO)", "errno:%d\n",
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errno))
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return -1;
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return 0;
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}
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static int settcpca(int fd, const char *tcp_ca)
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{
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int err;
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err = setsockopt(fd, IPPROTO_TCP, TCP_CONGESTION, tcp_ca, strlen(tcp_ca));
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if (CHECK(err == -1, "setsockopt(fd, TCP_CONGESTION)", "errno:%d\n",
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errno))
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return -1;
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return 0;
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}
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static void *server(void *arg)
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{
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int lfd = (int)(long)arg, err = 0, fd;
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ssize_t nr_sent = 0, bytes = 0;
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char batch[1500];
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fd = accept(lfd, NULL, NULL);
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while (fd == -1) {
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if (errno == EINTR)
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continue;
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err = -errno;
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goto done;
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}
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if (settimeo(fd)) {
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err = -errno;
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goto done;
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}
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while (bytes < total_bytes && !READ_ONCE(stop)) {
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nr_sent = send(fd, &batch,
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min(total_bytes - bytes, sizeof(batch)), 0);
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if (nr_sent == -1 && errno == EINTR)
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continue;
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if (nr_sent == -1) {
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err = -errno;
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break;
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}
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bytes += nr_sent;
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}
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CHECK(bytes != total_bytes, "send", "%zd != %u nr_sent:%zd errno:%d\n",
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bytes, total_bytes, nr_sent, errno);
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done:
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if (fd != -1)
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close(fd);
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if (err) {
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WRITE_ONCE(stop, 1);
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return ERR_PTR(err);
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}
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return NULL;
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}
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static void do_test(const char *tcp_ca)
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{
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struct sockaddr_in6 sa6 = {};
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ssize_t nr_recv = 0, bytes = 0;
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int lfd = -1, fd = -1;
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pthread_t srv_thread;
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socklen_t addrlen = sizeof(sa6);
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void *thread_ret;
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char batch[1500];
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int err;
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WRITE_ONCE(stop, 0);
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lfd = socket(AF_INET6, SOCK_STREAM, 0);
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if (CHECK(lfd == -1, "socket", "errno:%d\n", errno))
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return;
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fd = socket(AF_INET6, SOCK_STREAM, 0);
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if (CHECK(fd == -1, "socket", "errno:%d\n", errno)) {
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close(lfd);
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return;
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}
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if (settcpca(lfd, tcp_ca) || settcpca(fd, tcp_ca) ||
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settimeo(lfd) || settimeo(fd))
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goto done;
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/* bind, listen and start server thread to accept */
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sa6.sin6_family = AF_INET6;
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sa6.sin6_addr = in6addr_loopback;
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err = bind(lfd, (struct sockaddr *)&sa6, addrlen);
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if (CHECK(err == -1, "bind", "errno:%d\n", errno))
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goto done;
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err = getsockname(lfd, (struct sockaddr *)&sa6, &addrlen);
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if (CHECK(err == -1, "getsockname", "errno:%d\n", errno))
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goto done;
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err = listen(lfd, 1);
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if (CHECK(err == -1, "listen", "errno:%d\n", errno))
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goto done;
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err = pthread_create(&srv_thread, NULL, server, (void *)(long)lfd);
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if (CHECK(err != 0, "pthread_create", "err:%d\n", err))
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goto done;
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/* connect to server */
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err = connect(fd, (struct sockaddr *)&sa6, addrlen);
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if (CHECK(err == -1, "connect", "errno:%d\n", errno))
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goto wait_thread;
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/* recv total_bytes */
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while (bytes < total_bytes && !READ_ONCE(stop)) {
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nr_recv = recv(fd, &batch,
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min(total_bytes - bytes, sizeof(batch)), 0);
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if (nr_recv == -1 && errno == EINTR)
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continue;
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if (nr_recv == -1)
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break;
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bytes += nr_recv;
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}
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CHECK(bytes != total_bytes, "recv", "%zd != %u nr_recv:%zd errno:%d\n",
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bytes, total_bytes, nr_recv, errno);
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wait_thread:
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WRITE_ONCE(stop, 1);
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pthread_join(srv_thread, &thread_ret);
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CHECK(IS_ERR(thread_ret), "pthread_join", "thread_ret:%ld",
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PTR_ERR(thread_ret));
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done:
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close(lfd);
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close(fd);
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}
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static void test_dctcp(void)
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{
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struct bpf_dctcp *dctcp_skel;
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struct bpf_link *link;
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dctcp_skel = bpf_dctcp__open_and_load();
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if (CHECK(!dctcp_skel, "bpf_dctcp__open_and_load", "failed\n"))
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return;
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link = bpf_map__attach_struct_ops(dctcp_skel->maps.dctcp);
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if (CHECK(IS_ERR(link), "bpf_map__attach_struct_ops", "err:%ld\n",
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PTR_ERR(link))) {
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bpf_dctcp__destroy(dctcp_skel);
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return;
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}
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do_test("bpf_dctcp");
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bpf_link__destroy(link);
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bpf_dctcp__destroy(dctcp_skel);
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}
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void test_bpf_tcp_ca(void)
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{
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if (test__start_subtest("dctcp"))
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test_dctcp();
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}
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@ -0,0 +1,210 @@
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// SPDX-License-Identifier: GPL-2.0
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/* Copyright (c) 2019 Facebook */
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/* WARNING: This implemenation is not necessarily the same
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* as the tcp_dctcp.c. The purpose is mainly for testing
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* the kernel BPF logic.
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*/
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#include <linux/bpf.h>
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#include <linux/types.h>
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#include "bpf_tcp_helpers.h"
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char _license[] SEC("license") = "GPL";
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#define DCTCP_MAX_ALPHA 1024U
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struct dctcp {
|
||||
__u32 old_delivered;
|
||||
__u32 old_delivered_ce;
|
||||
__u32 prior_rcv_nxt;
|
||||
__u32 dctcp_alpha;
|
||||
__u32 next_seq;
|
||||
__u32 ce_state;
|
||||
__u32 loss_cwnd;
|
||||
};
|
||||
|
||||
static unsigned int dctcp_shift_g = 4; /* g = 1/2^4 */
|
||||
static unsigned int dctcp_alpha_on_init = DCTCP_MAX_ALPHA;
|
||||
|
||||
static __always_inline void dctcp_reset(const struct tcp_sock *tp,
|
||||
struct dctcp *ca)
|
||||
{
|
||||
ca->next_seq = tp->snd_nxt;
|
||||
|
||||
ca->old_delivered = tp->delivered;
|
||||
ca->old_delivered_ce = tp->delivered_ce;
|
||||
}
|
||||
|
||||
BPF_TCP_OPS_1(dctcp_init, void, struct sock *, sk)
|
||||
{
|
||||
const struct tcp_sock *tp = tcp_sk(sk);
|
||||
struct dctcp *ca = inet_csk_ca(sk);
|
||||
|
||||
ca->prior_rcv_nxt = tp->rcv_nxt;
|
||||
ca->dctcp_alpha = min(dctcp_alpha_on_init, DCTCP_MAX_ALPHA);
|
||||
ca->loss_cwnd = 0;
|
||||
ca->ce_state = 0;
|
||||
|
||||
dctcp_reset(tp, ca);
|
||||
}
|
||||
|
||||
BPF_TCP_OPS_1(dctcp_ssthresh, __u32, struct sock *, sk)
|
||||
{
|
||||
struct dctcp *ca = inet_csk_ca(sk);
|
||||
struct tcp_sock *tp = tcp_sk(sk);
|
||||
|
||||
ca->loss_cwnd = tp->snd_cwnd;
|
||||
return max(tp->snd_cwnd - ((tp->snd_cwnd * ca->dctcp_alpha) >> 11U), 2U);
|
||||
}
|
||||
|
||||
BPF_TCP_OPS_2(dctcp_update_alpha, void,
|
||||
struct sock *, sk, __u32, flags)
|
||||
{
|
||||
const struct tcp_sock *tp = tcp_sk(sk);
|
||||
struct dctcp *ca = inet_csk_ca(sk);
|
||||
|
||||
/* Expired RTT */
|
||||
if (!before(tp->snd_una, ca->next_seq)) {
|
||||
__u32 delivered_ce = tp->delivered_ce - ca->old_delivered_ce;
|
||||
__u32 alpha = ca->dctcp_alpha;
|
||||
|
||||
/* alpha = (1 - g) * alpha + g * F */
|
||||
|
||||
alpha -= min_not_zero(alpha, alpha >> dctcp_shift_g);
|
||||
if (delivered_ce) {
|
||||
__u32 delivered = tp->delivered - ca->old_delivered;
|
||||
|
||||
/* If dctcp_shift_g == 1, a 32bit value would overflow
|
||||
* after 8 M packets.
|
||||
*/
|
||||
delivered_ce <<= (10 - dctcp_shift_g);
|
||||
delivered_ce /= max(1U, delivered);
|
||||
|
||||
alpha = min(alpha + delivered_ce, DCTCP_MAX_ALPHA);
|
||||
}
|
||||
ca->dctcp_alpha = alpha;
|
||||
dctcp_reset(tp, ca);
|
||||
}
|
||||
}
|
||||
|
||||
static __always_inline void dctcp_react_to_loss(struct sock *sk)
|
||||
{
|
||||
struct dctcp *ca = inet_csk_ca(sk);
|
||||
struct tcp_sock *tp = tcp_sk(sk);
|
||||
|
||||
ca->loss_cwnd = tp->snd_cwnd;
|
||||
tp->snd_ssthresh = max(tp->snd_cwnd >> 1U, 2U);
|
||||
}
|
||||
|
||||
BPF_TCP_OPS_2(dctcp_state, void, struct sock *, sk, __u8, new_state)
|
||||
{
|
||||
if (new_state == TCP_CA_Recovery &&
|
||||
new_state != BPF_CORE_READ_BITFIELD(inet_csk(sk), icsk_ca_state))
|
||||
dctcp_react_to_loss(sk);
|
||||
/* We handle RTO in dctcp_cwnd_event to ensure that we perform only
|
||||
* one loss-adjustment per RTT.
|
||||
*/
|
||||
}
|
||||
|
||||
static __always_inline void dctcp_ece_ack_cwr(struct sock *sk, __u32 ce_state)
|
||||
{
|
||||
struct tcp_sock *tp = tcp_sk(sk);
|
||||
|
||||
if (ce_state == 1)
|
||||
tp->ecn_flags |= TCP_ECN_DEMAND_CWR;
|
||||
else
|
||||
tp->ecn_flags &= ~TCP_ECN_DEMAND_CWR;
|
||||
}
|
||||
|
||||
/* Minimal DCTP CE state machine:
|
||||
*
|
||||
* S: 0 <- last pkt was non-CE
|
||||
* 1 <- last pkt was CE
|
||||
*/
|
||||
static __always_inline
|
||||
void dctcp_ece_ack_update(struct sock *sk, enum tcp_ca_event evt,
|
||||
__u32 *prior_rcv_nxt, __u32 *ce_state)
|
||||
{
|
||||
__u32 new_ce_state = (evt == CA_EVENT_ECN_IS_CE) ? 1 : 0;
|
||||
|
||||
if (*ce_state != new_ce_state) {
|
||||
/* CE state has changed, force an immediate ACK to
|
||||
* reflect the new CE state. If an ACK was delayed,
|
||||
* send that first to reflect the prior CE state.
|
||||
*/
|
||||
if (inet_csk(sk)->icsk_ack.pending & ICSK_ACK_TIMER) {
|
||||
dctcp_ece_ack_cwr(sk, *ce_state);
|
||||
bpf_tcp_send_ack(sk, *prior_rcv_nxt);
|
||||
}
|
||||
inet_csk(sk)->icsk_ack.pending |= ICSK_ACK_NOW;
|
||||
}
|
||||
*prior_rcv_nxt = tcp_sk(sk)->rcv_nxt;
|
||||
*ce_state = new_ce_state;
|
||||
dctcp_ece_ack_cwr(sk, new_ce_state);
|
||||
}
|
||||
|
||||
BPF_TCP_OPS_2(dctcp_cwnd_event, void,
|
||||
struct sock *, sk, enum tcp_ca_event, ev)
|
||||
{
|
||||
struct dctcp *ca = inet_csk_ca(sk);
|
||||
|
||||
switch (ev) {
|
||||
case CA_EVENT_ECN_IS_CE:
|
||||
case CA_EVENT_ECN_NO_CE:
|
||||
dctcp_ece_ack_update(sk, ev, &ca->prior_rcv_nxt, &ca->ce_state);
|
||||
break;
|
||||
case CA_EVENT_LOSS:
|
||||
dctcp_react_to_loss(sk);
|
||||
break;
|
||||
default:
|
||||
/* Don't care for the rest. */
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
BPF_TCP_OPS_1(dctcp_cwnd_undo, __u32, struct sock *, sk)
|
||||
{
|
||||
const struct dctcp *ca = inet_csk_ca(sk);
|
||||
|
||||
return max(tcp_sk(sk)->snd_cwnd, ca->loss_cwnd);
|
||||
}
|
||||
|
||||
BPF_TCP_OPS_3(tcp_reno_cong_avoid, void,
|
||||
struct sock *, sk, __u32, ack, __u32, acked)
|
||||
{
|
||||
struct tcp_sock *tp = tcp_sk(sk);
|
||||
|
||||
if (!tcp_is_cwnd_limited(sk))
|
||||
return;
|
||||
|
||||
/* In "safe" area, increase. */
|
||||
if (tcp_in_slow_start(tp)) {
|
||||
acked = tcp_slow_start(tp, acked);
|
||||
if (!acked)
|
||||
return;
|
||||
}
|
||||
/* In dangerous area, increase slowly. */
|
||||
tcp_cong_avoid_ai(tp, tp->snd_cwnd, acked);
|
||||
}
|
||||
|
||||
SEC(".struct_ops")
|
||||
struct tcp_congestion_ops dctcp_nouse = {
|
||||
.init = (void *)dctcp_init,
|
||||
.set_state = (void *)dctcp_state,
|
||||
.flags = TCP_CONG_NEEDS_ECN,
|
||||
.name = "bpf_dctcp_nouse",
|
||||
};
|
||||
|
||||
SEC(".struct_ops")
|
||||
struct tcp_congestion_ops dctcp = {
|
||||
.init = (void *)dctcp_init,
|
||||
.in_ack_event = (void *)dctcp_update_alpha,
|
||||
.cwnd_event = (void *)dctcp_cwnd_event,
|
||||
.ssthresh = (void *)dctcp_ssthresh,
|
||||
.cong_avoid = (void *)tcp_reno_cong_avoid,
|
||||
.undo_cwnd = (void *)dctcp_cwnd_undo,
|
||||
.set_state = (void *)dctcp_state,
|
||||
.flags = TCP_CONG_NEEDS_ECN,
|
||||
.name = "bpf_dctcp",
|
||||
};
|
||||
Loading…
Reference in New Issue