1 /*- 2 * 3 * SPDX-License-Identifier: BSD-3-Clause 4 * 5 * Copyright (c) 2018-2020 6 * Netflix Inc. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * __FBSDID("$FreeBSD$"); 29 * 30 */ 31 /** 32 * Author: Randall Stewart <rrs@netflix.com> 33 */ 34 #ifndef __tcp_ratelimit_h__ 35 #define __tcp_ratelimit_h__ 36 37 struct m_snd_tag; 38 39 #define RL_MIN_DIVISOR 50 40 #define RL_DEFAULT_DIVISOR 1000 41 42 /* Flags on an individual rate */ 43 #define HDWRPACE_INITED 0x0001 44 #define HDWRPACE_TAGPRESENT 0x0002 45 #define HDWRPACE_IFPDEPARTED 0x0004 46 struct tcp_hwrate_limit_table { 47 const struct tcp_rate_set *ptbl; /* Pointer to parent table */ 48 struct m_snd_tag *tag; /* Send tag if needed (chelsio) */ 49 long rate; /* Rate we get in Bytes per second (Bps) */ 50 long using; /* How many flows are using this hdwr rate. */ 51 long rs_num_enobufs; 52 uint32_t time_between; /* Time-Gap between packets at this rate */ 53 uint32_t flags; 54 }; 55 56 /* Rateset flags */ 57 #define RS_IS_DEFF 0x0001 /* Its a lagg, do a double lookup */ 58 #define RS_IS_INTF 0x0002 /* Its a plain interface */ 59 #define RS_NO_PRE 0x0004 /* The interfacd has set rates */ 60 #define RS_INT_TBL 0x0010 /* 61 * The table is the internal version 62 * which has special setup requirements. 63 */ 64 #define RS_IS_DEAD 0x0020 /* The RS is dead list */ 65 #define RS_FUNERAL_SCHD 0x0040 /* Is a epoch call scheduled to bury this guy?*/ 66 #define RS_INTF_NO_SUP 0x0100 /* The interface does not support the ratelimiting */ 67 68 struct tcp_rate_set { 69 struct sysctl_ctx_list sysctl_ctx; 70 CK_LIST_ENTRY(tcp_rate_set) next; 71 struct ifnet *rs_ifp; 72 struct tcp_hwrate_limit_table *rs_rlt; 73 uint64_t rs_flows_using; 74 uint64_t rs_flow_limit; 75 uint32_t rs_if_dunit; 76 int rs_rate_cnt; 77 int rs_min_seg; 78 int rs_highest_valid; 79 int rs_lowest_valid; 80 int rs_disable; 81 int rs_flags; 82 struct epoch_context rs_epoch_ctx; 83 }; 84 85 CK_LIST_HEAD(head_tcp_rate_set, tcp_rate_set); 86 87 /* Request flags */ 88 #define RS_PACING_EXACT_MATCH 0x0001 /* Need an exact match for rate */ 89 #define RS_PACING_GT 0x0002 /* Greater than requested */ 90 #define RS_PACING_GEQ 0x0004 /* Greater than or equal too */ 91 #define RS_PACING_LT 0x0008 /* Less than requested rate */ 92 #define RS_PACING_SUB_OK 0x0010 /* If a rate can't be found get the 93 * next best rate (highest or lowest). */ 94 #ifdef _KERNEL 95 #ifndef ETHERNET_SEGMENT_SIZE 96 #define ETHERNET_SEGMENT_SIZE 1514 97 #endif 98 #ifdef RATELIMIT 99 #define DETAILED_RATELIMIT_SYSCTL 1 /* 100 * Undefine this if you don't want 101 * detailed rates to appear in 102 * net.inet.tcp.rl. 103 * With the defintion each rate 104 * shows up in your sysctl tree 105 * this can be big. 106 */ 107 uint64_t inline 108 tcp_hw_highest_rate(const struct tcp_hwrate_limit_table *rle) 109 { 110 return (rle->ptbl->rs_rlt[rle->ptbl->rs_highest_valid].rate); 111 } 112 113 uint64_t 114 tcp_hw_highest_rate_ifp(struct ifnet *ifp, struct inpcb *inp); 115 116 const struct tcp_hwrate_limit_table * 117 tcp_set_pacing_rate(struct tcpcb *tp, struct ifnet *ifp, 118 uint64_t bytes_per_sec, int flags, int *error, uint64_t *lower_rate); 119 120 const struct tcp_hwrate_limit_table * 121 tcp_chg_pacing_rate(const struct tcp_hwrate_limit_table *crte, 122 struct tcpcb *tp, struct ifnet *ifp, 123 uint64_t bytes_per_sec, int flags, int *error, uint64_t *lower_rate); 124 void 125 tcp_rel_pacing_rate(const struct tcp_hwrate_limit_table *crte, 126 struct tcpcb *tp); 127 128 uint32_t 129 tcp_get_pacing_burst_size_w_divisor(struct tcpcb *tp, uint64_t bw, uint32_t segsiz, int can_use_1mss, 130 const struct tcp_hwrate_limit_table *te, int *err, int divisor); 131 132 void 133 tcp_rl_log_enobuf(const struct tcp_hwrate_limit_table *rte); 134 135 #else 136 static inline const struct tcp_hwrate_limit_table * 137 tcp_set_pacing_rate(struct tcpcb *tp, struct ifnet *ifp, 138 uint64_t bytes_per_sec, int flags, int *error, uint64_t *lower_rate) 139 { 140 if (error) 141 *error = EOPNOTSUPP; 142 return (NULL); 143 } 144 145 static inline const struct tcp_hwrate_limit_table * 146 tcp_chg_pacing_rate(const struct tcp_hwrate_limit_table *crte, 147 struct tcpcb *tp, struct ifnet *ifp, 148 uint64_t bytes_per_sec, int flags, int *error, uint64_t *lower_rate) 149 { 150 if (error) 151 *error = EOPNOTSUPP; 152 return (NULL); 153 } 154 155 static inline void 156 tcp_rel_pacing_rate(const struct tcp_hwrate_limit_table *crte, 157 struct tcpcb *tp) 158 { 159 return; 160 } 161 162 static uint64_t inline 163 tcp_hw_highest_rate(const struct tcp_hwrate_limit_table *rle) 164 { 165 return (0); 166 } 167 168 static uint64_t inline 169 tcp_hw_highest_rate_ifp(struct ifnet *ifp, struct inpcb *inp) 170 { 171 return (0); 172 } 173 174 static inline uint32_t 175 tcp_get_pacing_burst_size_w_divisor(struct tcpcb *tp, uint64_t bw, uint32_t segsiz, int can_use_1mss, 176 const struct tcp_hwrate_limit_table *te, int *err, int divisor) 177 { 178 /* 179 * We use the google formula to calculate the 180 * TSO size. I.E. 181 * bw < 24Meg 182 * tso = 2mss 183 * else 184 * tso = min(bw/(div=1000), 64k) 185 * 186 * Note for these calculations we ignore the 187 * packet overhead (enet hdr, ip hdr and tcp hdr). 188 * We only get the google formula when we have 189 * divisor = 1000, which is the default for now. 190 */ 191 uint64_t bytes; 192 uint32_t new_tso, min_tso_segs; 193 194 /* It can't be zero */ 195 if ((divisor == 0) || 196 (divisor < RL_MIN_DIVISOR)) { 197 bytes = bw / RL_DEFAULT_DIVISOR; 198 } else 199 bytes = bw / divisor; 200 /* We can't ever send more than 65k in a TSO */ 201 if (bytes > 0xffff) { 202 bytes = 0xffff; 203 } 204 /* Round up */ 205 new_tso = (bytes + segsiz - 1) / segsiz; 206 if (can_use_1mss) 207 min_tso_segs = 1; 208 else 209 min_tso_segs = 2; 210 if (new_tso < min_tso_segs) 211 new_tso = min_tso_segs; 212 new_tso *= segsiz; 213 return (new_tso); 214 } 215 216 /* Do nothing if RATELIMIT is not defined */ 217 static void 218 tcp_rl_log_enobuf(const struct tcp_hwrate_limit_table *rte) 219 { 220 } 221 222 #endif 223 224 /* 225 * Given a b/w and a segsiz, and optional hardware 226 * rate limit, return the ideal size to burst 227 * out at once. Note the parameter can_use_1mss 228 * dictates if the transport will tolerate a 1mss 229 * limit, if not it will bottom out at 2mss (think 230 * delayed ack). 231 */ 232 static inline uint32_t 233 tcp_get_pacing_burst_size(struct tcpcb *tp, uint64_t bw, uint32_t segsiz, int can_use_1mss, 234 const struct tcp_hwrate_limit_table *te, int *err) 235 { 236 237 return (tcp_get_pacing_burst_size_w_divisor(tp, bw, segsiz, 238 can_use_1mss, 239 te, err, 0)); 240 } 241 242 #endif 243 #endif 244