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 * 29 */ 30 /** 31 * Author: Randall Stewart <rrs@netflix.com> 32 */ 33 #ifndef __tcp_ratelimit_h__ 34 #define __tcp_ratelimit_h__ 35 36 struct m_snd_tag; 37 38 #define RL_MIN_DIVISOR 50 39 #define RL_DEFAULT_DIVISOR 1000 40 41 /* Flags on an individual rate */ 42 #define HDWRPACE_INITED 0x0001 43 #define HDWRPACE_TAGPRESENT 0x0002 44 #define HDWRPACE_IFPDEPARTED 0x0004 45 struct tcp_hwrate_limit_table { 46 const struct tcp_rate_set *ptbl; /* Pointer to parent table */ 47 struct m_snd_tag *tag; /* Send tag if needed (chelsio) */ 48 long rate; /* Rate we get in Bytes per second (Bps) */ 49 long using; /* How many flows are using this hdwr rate. */ 50 long rs_num_enobufs; 51 uint32_t time_between; /* Time-Gap between packets at this rate */ 52 uint32_t flags; 53 }; 54 55 /* Rateset flags */ 56 #define RS_IS_DEFF 0x0001 /* Its a lagg, do a double lookup */ 57 #define RS_IS_INTF 0x0002 /* Its a plain interface */ 58 #define RS_NO_PRE 0x0004 /* The interfacd has set rates */ 59 #define RS_INT_TBL 0x0010 /* 60 * The table is the internal version 61 * which has special setup requirements. 62 */ 63 #define RS_IS_DEAD 0x0020 /* The RS is dead list */ 64 #define RS_FUNERAL_SCHD 0x0040 /* Is a epoch call scheduled to bury this guy?*/ 65 #define RS_INTF_NO_SUP 0x0100 /* The interface does not support the ratelimiting */ 66 67 struct tcp_rate_set { 68 struct sysctl_ctx_list sysctl_ctx; 69 CK_LIST_ENTRY(tcp_rate_set) next; 70 struct ifnet *rs_ifp; 71 struct tcp_hwrate_limit_table *rs_rlt; 72 uint64_t rs_flows_using; 73 uint64_t rs_flow_limit; 74 uint32_t rs_if_dunit; 75 int rs_rate_cnt; 76 int rs_min_seg; 77 int rs_highest_valid; 78 int rs_lowest_valid; 79 int rs_disable; 80 int rs_flags; 81 struct epoch_context rs_epoch_ctx; 82 }; 83 84 CK_LIST_HEAD(head_tcp_rate_set, tcp_rate_set); 85 86 /* Request flags */ 87 #define RS_PACING_EXACT_MATCH 0x0001 /* Need an exact match for rate */ 88 #define RS_PACING_GT 0x0002 /* Greater than requested */ 89 #define RS_PACING_GEQ 0x0004 /* Greater than or equal too */ 90 #define RS_PACING_LT 0x0008 /* Less than requested rate */ 91 #define RS_PACING_SUB_OK 0x0010 /* If a rate can't be found get the 92 * next best rate (highest or lowest). */ 93 #ifdef _KERNEL 94 #ifndef ETHERNET_SEGMENT_SIZE 95 #define ETHERNET_SEGMENT_SIZE 1514 96 #endif 97 #ifdef RATELIMIT 98 #define DETAILED_RATELIMIT_SYSCTL 1 /* 99 * Undefine this if you don't want 100 * detailed rates to appear in 101 * net.inet.tcp.rl. 102 * With the defintion each rate 103 * shows up in your sysctl tree 104 * this can be big. 105 */ 106 uint64_t inline 107 tcp_hw_highest_rate(const struct tcp_hwrate_limit_table *rle) 108 { 109 return (rle->ptbl->rs_rlt[rle->ptbl->rs_highest_valid].rate); 110 } 111 112 uint64_t 113 tcp_hw_highest_rate_ifp(struct ifnet *ifp, struct inpcb *inp); 114 115 const struct tcp_hwrate_limit_table * 116 tcp_set_pacing_rate(struct tcpcb *tp, struct ifnet *ifp, 117 uint64_t bytes_per_sec, int flags, int *error, uint64_t *lower_rate); 118 119 const struct tcp_hwrate_limit_table * 120 tcp_chg_pacing_rate(const struct tcp_hwrate_limit_table *crte, 121 struct tcpcb *tp, struct ifnet *ifp, 122 uint64_t bytes_per_sec, int flags, int *error, uint64_t *lower_rate); 123 void 124 tcp_rel_pacing_rate(const struct tcp_hwrate_limit_table *crte, 125 struct tcpcb *tp); 126 127 uint32_t 128 tcp_get_pacing_burst_size_w_divisor(struct tcpcb *tp, uint64_t bw, uint32_t segsiz, int can_use_1mss, 129 const struct tcp_hwrate_limit_table *te, int *err, int divisor); 130 131 void 132 tcp_rl_log_enobuf(const struct tcp_hwrate_limit_table *rte); 133 134 #else 135 static inline const struct tcp_hwrate_limit_table * 136 tcp_set_pacing_rate(struct tcpcb *tp, struct ifnet *ifp, 137 uint64_t bytes_per_sec, int flags, int *error, uint64_t *lower_rate) 138 { 139 if (error) 140 *error = EOPNOTSUPP; 141 return (NULL); 142 } 143 144 static inline const struct tcp_hwrate_limit_table * 145 tcp_chg_pacing_rate(const struct tcp_hwrate_limit_table *crte, 146 struct tcpcb *tp, struct ifnet *ifp, 147 uint64_t bytes_per_sec, int flags, int *error, uint64_t *lower_rate) 148 { 149 if (error) 150 *error = EOPNOTSUPP; 151 return (NULL); 152 } 153 154 static inline void 155 tcp_rel_pacing_rate(const struct tcp_hwrate_limit_table *crte, 156 struct tcpcb *tp) 157 { 158 return; 159 } 160 161 static uint64_t inline 162 tcp_hw_highest_rate(const struct tcp_hwrate_limit_table *rle) 163 { 164 return (0); 165 } 166 167 static uint64_t inline 168 tcp_hw_highest_rate_ifp(struct ifnet *ifp, struct inpcb *inp) 169 { 170 return (0); 171 } 172 173 static inline uint32_t 174 tcp_get_pacing_burst_size_w_divisor(struct tcpcb *tp, uint64_t bw, uint32_t segsiz, int can_use_1mss, 175 const struct tcp_hwrate_limit_table *te, int *err, int divisor) 176 { 177 /* 178 * We use the google formula to calculate the 179 * TSO size. I.E. 180 * bw < 24Meg 181 * tso = 2mss 182 * else 183 * tso = min(bw/(div=1000), 64k) 184 * 185 * Note for these calculations we ignore the 186 * packet overhead (enet hdr, ip hdr and tcp hdr). 187 * We only get the google formula when we have 188 * divisor = 1000, which is the default for now. 189 */ 190 uint64_t bytes; 191 uint32_t new_tso, min_tso_segs; 192 193 /* It can't be zero */ 194 if ((divisor == 0) || 195 (divisor < RL_MIN_DIVISOR)) { 196 bytes = bw / RL_DEFAULT_DIVISOR; 197 } else 198 bytes = bw / divisor; 199 /* We can't ever send more than 65k in a TSO */ 200 if (bytes > 0xffff) { 201 bytes = 0xffff; 202 } 203 /* Round up */ 204 new_tso = (bytes + segsiz - 1) / segsiz; 205 if (can_use_1mss) 206 min_tso_segs = 1; 207 else 208 min_tso_segs = 2; 209 if (new_tso < min_tso_segs) 210 new_tso = min_tso_segs; 211 new_tso *= segsiz; 212 return (new_tso); 213 } 214 215 /* Do nothing if RATELIMIT is not defined */ 216 static void 217 tcp_rl_log_enobuf(const struct tcp_hwrate_limit_table *rte) 218 { 219 } 220 221 #endif 222 223 /* 224 * Given a b/w and a segsiz, and optional hardware 225 * rate limit, return the ideal size to burst 226 * out at once. Note the parameter can_use_1mss 227 * dictates if the transport will tolerate a 1mss 228 * limit, if not it will bottom out at 2mss (think 229 * delayed ack). 230 */ 231 static inline uint32_t 232 tcp_get_pacing_burst_size(struct tcpcb *tp, uint64_t bw, uint32_t segsiz, int can_use_1mss, 233 const struct tcp_hwrate_limit_table *te, int *err) 234 { 235 236 return (tcp_get_pacing_burst_size_w_divisor(tp, bw, segsiz, 237 can_use_1mss, 238 te, err, 0)); 239 } 240 241 #endif 242 #endif 243