/*- * * SPDX-License-Identifier: BSD-3-Clause * * Copyright (c) 2018-2020 * Netflix Inc. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * */ /** * Author: Randall Stewart */ #include __FBSDID("$FreeBSD$"); #include "opt_inet.h" #include "opt_inet6.h" #include "opt_ipsec.h" #include "opt_tcpdebug.h" #include "opt_ratelimit.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define TCPSTATES /* for logging */ #include #ifdef INET6 #include #endif #include #include #include #ifndef USECS_IN_SECOND #define USECS_IN_SECOND 1000000 #endif /* * For the purposes of each send, what is the size * of an ethernet frame. */ MALLOC_DEFINE(M_TCPPACE, "tcp_hwpace", "TCP Hardware pacing memory"); #ifdef RATELIMIT /* * The following preferred table will seem weird to * the casual viewer. Why do we not have any rates below * 1Mbps? Why do we have a rate at 1.44Mbps called common? * Why do the rates cluster in the 1-100Mbps range more * than others? Why does the table jump around at the beginnign * and then be more consistently raising? * * Let me try to answer those questions. A lot of * this is dependant on the hardware. We have three basic * supporters of rate limiting * * Chelsio - Supporting 16 configurable rates. * Mlx - c4 supporting 13 fixed rates. * Mlx - c5 & c6 supporting 127 configurable rates. * * The c4 is why we have a common rate that is available * in all rate tables. This is a selected rate from the * c4 table and we assure its available in all ratelimit * tables. This way the tcp_ratelimit code has an assured * rate it should always be able to get. This answers a * couple of the questions above. * * So what about the rest, well the table is built to * try to get the most out of a joint hardware/software * pacing system. The software pacer will always pick * a rate higher than the b/w that it is estimating * * on the path. This is done for two reasons. * a) So we can discover more b/w * and * b) So we can send a block of MSS's down and then * have the software timer go off after the previous * send is completely out of the hardware. * * But when we do we don't want to have the delay * between the last packet sent by the hardware be * excessively long (to reach our desired rate). * * So let me give an example for clarity. * * Lets assume that the tcp stack sees that 29,110,000 bps is * what the bw of the path is. The stack would select the * rate 31Mbps. 31Mbps means that each send that is done * by the hardware will cause a 390 micro-second gap between * the packets sent at that rate. For 29,110,000 bps we * would need 416 micro-seconds gap between each send. * * Note that are calculating a complete time for pacing * which includes the ethernet, IP and TCP overhead. So * a full 1514 bytes is used for the above calculations. * My testing has shown that both cards are also using this * as their basis i.e. full payload size of the ethernet frame. * The TCP stack caller needs to be aware of this and make the * appropriate overhead calculations be included in its choices. * * Now, continuing our example, we pick a MSS size based on the * delta between the two rates (416 - 390) divided into the rate * we really wish to send at rounded up. That results in a MSS * send of 17 mss's at once. The hardware then will * run out of data in a single 17MSS send in 6,630 micro-seconds. * * On the other hand the software pacer will send more data * in 7,072 micro-seconds. This means that we will refill * the hardware 52 microseconds after it would have sent * next if it had not ran out of data. This is a win since we are * only sending every 7ms or so and yet all the packets are spaced on * the wire with 94% of what they should be and only * the last packet is delayed extra to make up for the * difference. * * Note that the above formula has two important caveat. * If we are above (b/w wise) over 100Mbps we double the result * of the MSS calculation. The second caveat is if we are 500Mbps * or more we just send the maximum MSS at once i.e. 45MSS. At * the higher b/w's even the cards have limits to what times (timer granularity) * they can insert between packets and start to send more than one * packet at a time on the wire. * */ #define COMMON_RATE 180500 const uint64_t desired_rates[] = { 122500, /* 1Mbps - rate 1 */ 180500, /* 1.44Mpbs - rate 2 common rate */ 375000, /* 3Mbps - rate 3 */ 625000, /* 5Mbps - rate 4 */ 1250000, /* 10Mbps - rate 5 */ 1875000, /* 15Mbps - rate 6 */ 2500000, /* 20Mbps - rate 7 */ 3125000, /* 25Mbps - rate 8 */ 3750000, /* 30Mbps - rate 9 */ 4375000, /* 35Mbps - rate 10 */ 5000000, /* 40Meg - rate 11 */ 6250000, /* 50Mbps - rate 12 */ 12500000, /* 100Mbps - rate 13 */ 25000000, /* 200Mbps - rate 14 */ 50000000, /* 400Mbps - rate 15 */ 100000000, /* 800Mbps - rate 16 */ 5625000, /* 45Mbps - rate 17 */ 6875000, /* 55Mbps - rate 19 */ 7500000, /* 60Mbps - rate 20 */ 8125000, /* 65Mbps - rate 21 */ 8750000, /* 70Mbps - rate 22 */ 9375000, /* 75Mbps - rate 23 */ 10000000, /* 80Mbps - rate 24 */ 10625000, /* 85Mbps - rate 25 */ 11250000, /* 90Mbps - rate 26 */ 11875000, /* 95Mbps - rate 27 */ 12500000, /* 100Mbps - rate 28 */ 13750000, /* 110Mbps - rate 29 */ 15000000, /* 120Mbps - rate 30 */ 16250000, /* 130Mbps - rate 31 */ 17500000, /* 140Mbps - rate 32 */ 18750000, /* 150Mbps - rate 33 */ 20000000, /* 160Mbps - rate 34 */ 21250000, /* 170Mbps - rate 35 */ 22500000, /* 180Mbps - rate 36 */ 23750000, /* 190Mbps - rate 37 */ 26250000, /* 210Mbps - rate 38 */ 27500000, /* 220Mbps - rate 39 */ 28750000, /* 230Mbps - rate 40 */ 30000000, /* 240Mbps - rate 41 */ 31250000, /* 250Mbps - rate 42 */ 34375000, /* 275Mbps - rate 43 */ 37500000, /* 300Mbps - rate 44 */ 40625000, /* 325Mbps - rate 45 */ 43750000, /* 350Mbps - rate 46 */ 46875000, /* 375Mbps - rate 47 */ 53125000, /* 425Mbps - rate 48 */ 56250000, /* 450Mbps - rate 49 */ 59375000, /* 475Mbps - rate 50 */ 62500000, /* 500Mbps - rate 51 */ 68750000, /* 550Mbps - rate 52 */ 75000000, /* 600Mbps - rate 53 */ 81250000, /* 650Mbps - rate 54 */ 87500000, /* 700Mbps - rate 55 */ 93750000, /* 750Mbps - rate 56 */ 106250000, /* 850Mbps - rate 57 */ 112500000, /* 900Mbps - rate 58 */ 125000000, /* 1Gbps - rate 59 */ 156250000, /* 1.25Gps - rate 60 */ 187500000, /* 1.5Gps - rate 61 */ 218750000, /* 1.75Gps - rate 62 */ 250000000, /* 2Gbps - rate 63 */ 281250000, /* 2.25Gps - rate 64 */ 312500000, /* 2.5Gbps - rate 65 */ 343750000, /* 2.75Gbps - rate 66 */ 375000000, /* 3Gbps - rate 67 */ 500000000, /* 4Gbps - rate 68 */ 625000000, /* 5Gbps - rate 69 */ 750000000, /* 6Gbps - rate 70 */ 875000000, /* 7Gbps - rate 71 */ 1000000000, /* 8Gbps - rate 72 */ 1125000000, /* 9Gbps - rate 73 */ 1250000000, /* 10Gbps - rate 74 */ 1875000000, /* 15Gbps - rate 75 */ 2500000000 /* 20Gbps - rate 76 */ }; #define MAX_HDWR_RATES (sizeof(desired_rates)/sizeof(uint64_t)) #define RS_ORDERED_COUNT 16 /* * Number that are in order * at the beginning of the table, * over this a sort is required. */ #define RS_NEXT_ORDER_GROUP 16 /* * The point in our table where * we come fill in a second ordered * group (index wise means -1). */ #define ALL_HARDWARE_RATES 1004 /* * 1Meg - 1Gig in 1 Meg steps * plus 100, 200k and 500k and * 10Gig */ #define RS_ONE_MEGABIT_PERSEC 1000000 #define RS_ONE_GIGABIT_PERSEC 1000000000 #define RS_TEN_GIGABIT_PERSEC 10000000000 static struct head_tcp_rate_set int_rs; static struct mtx rs_mtx; uint32_t rs_number_alive; uint32_t rs_number_dead; static uint32_t rs_floor_mss = 0; static uint32_t wait_time_floor = 8000; /* 8 ms */ static uint32_t rs_hw_floor_mss = 16; static uint32_t num_of_waits_allowed = 1; /* How many time blocks are we willing to wait */ SYSCTL_NODE(_net_inet_tcp, OID_AUTO, rl, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, "TCP Ratelimit stats"); SYSCTL_UINT(_net_inet_tcp_rl, OID_AUTO, alive, CTLFLAG_RW, &rs_number_alive, 0, "Number of interfaces initialized for ratelimiting"); SYSCTL_UINT(_net_inet_tcp_rl, OID_AUTO, dead, CTLFLAG_RW, &rs_number_dead, 0, "Number of interfaces departing from ratelimiting"); SYSCTL_UINT(_net_inet_tcp_rl, OID_AUTO, floor_mss, CTLFLAG_RW, &rs_floor_mss, 0, "Number of MSS that will override the normal minimums (0 means don't enforce)"); SYSCTL_UINT(_net_inet_tcp_rl, OID_AUTO, wait_floor, CTLFLAG_RW, &wait_time_floor, 2000, "Has b/w increases what is the wait floor we are willing to wait at the end?"); SYSCTL_UINT(_net_inet_tcp_rl, OID_AUTO, time_blocks, CTLFLAG_RW, &num_of_waits_allowed, 1, "How many time blocks on the end should software pacing be willing to wait?"); SYSCTL_UINT(_net_inet_tcp_rl, OID_AUTO, hw_floor_mss, CTLFLAG_RW, &rs_hw_floor_mss, 16, "Number of mss that are a minum for hardware pacing?"); static void rl_add_syctl_entries(struct sysctl_oid *rl_sysctl_root, struct tcp_rate_set *rs) { /* * Add sysctl entries for thus interface. */ if (rs->rs_flags & RS_INTF_NO_SUP) { SYSCTL_ADD_S32(&rs->sysctl_ctx, SYSCTL_CHILDREN(rl_sysctl_root), OID_AUTO, "disable", CTLFLAG_RD, &rs->rs_disable, 0, "Disable this interface from new hdwr limiting?"); } else { SYSCTL_ADD_S32(&rs->sysctl_ctx, SYSCTL_CHILDREN(rl_sysctl_root), OID_AUTO, "disable", CTLFLAG_RW, &rs->rs_disable, 0, "Disable this interface from new hdwr limiting?"); } SYSCTL_ADD_S32(&rs->sysctl_ctx, SYSCTL_CHILDREN(rl_sysctl_root), OID_AUTO, "minseg", CTLFLAG_RW, &rs->rs_min_seg, 0, "What is the minimum we need to send on this interface?"); SYSCTL_ADD_U64(&rs->sysctl_ctx, SYSCTL_CHILDREN(rl_sysctl_root), OID_AUTO, "flow_limit", CTLFLAG_RW, &rs->rs_flow_limit, 0, "What is the limit for number of flows (0=unlimited)?"); SYSCTL_ADD_S32(&rs->sysctl_ctx, SYSCTL_CHILDREN(rl_sysctl_root), OID_AUTO, "highest", CTLFLAG_RD, &rs->rs_highest_valid, 0, "Highest valid rate"); SYSCTL_ADD_S32(&rs->sysctl_ctx, SYSCTL_CHILDREN(rl_sysctl_root), OID_AUTO, "lowest", CTLFLAG_RD, &rs->rs_lowest_valid, 0, "Lowest valid rate"); SYSCTL_ADD_S32(&rs->sysctl_ctx, SYSCTL_CHILDREN(rl_sysctl_root), OID_AUTO, "flags", CTLFLAG_RD, &rs->rs_flags, 0, "What lags are on the entry?"); SYSCTL_ADD_S32(&rs->sysctl_ctx, SYSCTL_CHILDREN(rl_sysctl_root), OID_AUTO, "numrates", CTLFLAG_RD, &rs->rs_rate_cnt, 0, "How many rates re there?"); SYSCTL_ADD_U64(&rs->sysctl_ctx, SYSCTL_CHILDREN(rl_sysctl_root), OID_AUTO, "flows_using", CTLFLAG_RD, &rs->rs_flows_using, 0, "How many flows are using this interface now?"); #ifdef DETAILED_RATELIMIT_SYSCTL if (rs->rs_rlt && rs->rs_rate_cnt > 0) { /* Lets display the rates */ int i; struct sysctl_oid *rl_rates; struct sysctl_oid *rl_rate_num; char rate_num[16]; rl_rates = SYSCTL_ADD_NODE(&rs->sysctl_ctx, SYSCTL_CHILDREN(rl_sysctl_root), OID_AUTO, "rate", CTLFLAG_RW | CTLFLAG_MPSAFE, 0, "Ratelist"); for( i = 0; i < rs->rs_rate_cnt; i++) { sprintf(rate_num, "%d", i); rl_rate_num = SYSCTL_ADD_NODE(&rs->sysctl_ctx, SYSCTL_CHILDREN(rl_rates), OID_AUTO, rate_num, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, "Individual Rate"); SYSCTL_ADD_U32(&rs->sysctl_ctx, SYSCTL_CHILDREN(rl_rate_num), OID_AUTO, "flags", CTLFLAG_RD, &rs->rs_rlt[i].flags, 0, "Flags on this rate"); SYSCTL_ADD_U32(&rs->sysctl_ctx, SYSCTL_CHILDREN(rl_rate_num), OID_AUTO, "pacetime", CTLFLAG_RD, &rs->rs_rlt[i].time_between, 0, "Time hardware inserts between 1500 byte sends"); SYSCTL_ADD_LONG(&rs->sysctl_ctx, SYSCTL_CHILDREN(rl_rate_num), OID_AUTO, "rate", CTLFLAG_RD, &rs->rs_rlt[i].rate, "Rate in bytes per second"); SYSCTL_ADD_LONG(&rs->sysctl_ctx, SYSCTL_CHILDREN(rl_rate_num), OID_AUTO, "using", CTLFLAG_RD, &rs->rs_rlt[i].using, "Number of flows using"); SYSCTL_ADD_LONG(&rs->sysctl_ctx, SYSCTL_CHILDREN(rl_rate_num), OID_AUTO, "enobufs", CTLFLAG_RD, &rs->rs_rlt[i].rs_num_enobufs, "Number of enobufs logged on this rate"); } } #endif } static void rs_destroy(epoch_context_t ctx) { struct tcp_rate_set *rs; bool do_free_rs; rs = __containerof(ctx, struct tcp_rate_set, rs_epoch_ctx); mtx_lock(&rs_mtx); rs->rs_flags &= ~RS_FUNERAL_SCHD; /* * In theory its possible (but unlikely) * that while the delete was occuring * and we were applying the DEAD flag * someone slipped in and found the * interface in a lookup. While we * decided rs_flows_using were 0 and * scheduling the epoch_call, the other * thread incremented rs_flow_using. This * is because users have a pointer and * we only use the rs_flows_using in an * atomic fashion, i.e. the other entities * are not protected. To assure this did * not occur, we check rs_flows_using here * before deleting. */ do_free_rs = (rs->rs_flows_using == 0); rs_number_dead--; mtx_unlock(&rs_mtx); if (do_free_rs) { sysctl_ctx_free(&rs->sysctl_ctx); free(rs->rs_rlt, M_TCPPACE); free(rs, M_TCPPACE); } } static void rs_defer_destroy(struct tcp_rate_set *rs) { mtx_assert(&rs_mtx, MA_OWNED); /* Check if already pending. */ if (rs->rs_flags & RS_FUNERAL_SCHD) return; rs_number_dead++; /* Set flag to only defer once. */ rs->rs_flags |= RS_FUNERAL_SCHD; NET_EPOCH_CALL(rs_destroy, &rs->rs_epoch_ctx); } #ifdef INET extern counter_u64_t rate_limit_new; extern counter_u64_t rate_limit_chg; extern counter_u64_t rate_limit_set_ok; extern counter_u64_t rate_limit_active; extern counter_u64_t rate_limit_alloc_fail; #endif static int rl_attach_txrtlmt(struct ifnet *ifp, uint32_t flowtype, int flowid, uint64_t cfg_rate, struct m_snd_tag **tag) { int error; union if_snd_tag_alloc_params params = { .rate_limit.hdr.type = IF_SND_TAG_TYPE_RATE_LIMIT, .rate_limit.hdr.flowid = flowid, .rate_limit.hdr.flowtype = flowtype, .rate_limit.max_rate = cfg_rate, .rate_limit.flags = M_NOWAIT, }; error = m_snd_tag_alloc(ifp, ¶ms, tag); #ifdef INET if (error == 0) { counter_u64_add(rate_limit_set_ok, 1); counter_u64_add(rate_limit_active, 1); } else if (error != EOPNOTSUPP) counter_u64_add(rate_limit_alloc_fail, 1); #endif return (error); } static void populate_canned_table(struct tcp_rate_set *rs, const uint64_t *rate_table_act) { /* * The internal table is "special", it * is two seperate ordered tables that * must be merged. We get here when the * adapter specifies a number of rates that * covers both ranges in the table in some * form. */ int i, at_low, at_high; uint8_t low_disabled = 0, high_disabled = 0; for(i = 0, at_low = 0, at_high = RS_NEXT_ORDER_GROUP; i < rs->rs_rate_cnt; i++) { rs->rs_rlt[i].flags = 0; rs->rs_rlt[i].time_between = 0; if ((low_disabled == 0) && (high_disabled || (rate_table_act[at_low] < rate_table_act[at_high]))) { rs->rs_rlt[i].rate = rate_table_act[at_low]; at_low++; if (at_low == RS_NEXT_ORDER_GROUP) low_disabled = 1; } else if (high_disabled == 0) { rs->rs_rlt[i].rate = rate_table_act[at_high]; at_high++; if (at_high == MAX_HDWR_RATES) high_disabled = 1; } } } static struct tcp_rate_set * rt_setup_new_rs(struct ifnet *ifp, int *error) { struct tcp_rate_set *rs; const uint64_t *rate_table_act; uint64_t lentim, res; size_t sz; uint32_t hash_type; int i; struct if_ratelimit_query_results rl; struct sysctl_oid *rl_sysctl_root; struct epoch_tracker et; /* * We expect to enter with the * mutex locked. */ if (ifp->if_ratelimit_query == NULL) { /* * We can do nothing if we cannot * get a query back from the driver. */ printf("Warning:No query functions for %s:%d-- failed\n", ifp->if_dname, ifp->if_dunit); return (NULL); } rs = malloc(sizeof(struct tcp_rate_set), M_TCPPACE, M_NOWAIT | M_ZERO); if (rs == NULL) { if (error) *error = ENOMEM; printf("Warning:No memory for malloc of tcp_rate_set\n"); return (NULL); } memset(&rl, 0, sizeof(rl)); rl.flags = RT_NOSUPPORT; ifp->if_ratelimit_query(ifp, &rl); if (rl.flags & RT_IS_UNUSABLE) { /* * The interface does not really support * the rate-limiting. */ memset(rs, 0, sizeof(struct tcp_rate_set)); rs->rs_ifp = ifp; rs->rs_if_dunit = ifp->if_dunit; rs->rs_flags = RS_INTF_NO_SUP; rs->rs_disable = 1; rs_number_alive++; sysctl_ctx_init(&rs->sysctl_ctx); rl_sysctl_root = SYSCTL_ADD_NODE(&rs->sysctl_ctx, SYSCTL_STATIC_CHILDREN(_net_inet_tcp_rl), OID_AUTO, rs->rs_ifp->if_xname, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, ""); rl_add_syctl_entries(rl_sysctl_root, rs); NET_EPOCH_ENTER(et); mtx_lock(&rs_mtx); CK_LIST_INSERT_HEAD(&int_rs, rs, next); mtx_unlock(&rs_mtx); NET_EPOCH_EXIT(et); return (rs); } else if ((rl.flags & RT_IS_INDIRECT) == RT_IS_INDIRECT) { memset(rs, 0, sizeof(struct tcp_rate_set)); rs->rs_ifp = ifp; rs->rs_if_dunit = ifp->if_dunit; rs->rs_flags = RS_IS_DEFF; rs_number_alive++; sysctl_ctx_init(&rs->sysctl_ctx); rl_sysctl_root = SYSCTL_ADD_NODE(&rs->sysctl_ctx, SYSCTL_STATIC_CHILDREN(_net_inet_tcp_rl), OID_AUTO, rs->rs_ifp->if_xname, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, ""); rl_add_syctl_entries(rl_sysctl_root, rs); NET_EPOCH_ENTER(et); mtx_lock(&rs_mtx); CK_LIST_INSERT_HEAD(&int_rs, rs, next); mtx_unlock(&rs_mtx); NET_EPOCH_EXIT(et); return (rs); } else if ((rl.flags & RT_IS_FIXED_TABLE) == RT_IS_FIXED_TABLE) { /* Mellanox C4 likely */ rs->rs_ifp = ifp; rs->rs_if_dunit = ifp->if_dunit; rs->rs_rate_cnt = rl.number_of_rates; rs->rs_min_seg = rl.min_segment_burst; rs->rs_highest_valid = 0; rs->rs_flow_limit = rl.max_flows; rs->rs_flags = RS_IS_INTF | RS_NO_PRE; rs->rs_disable = 0; rate_table_act = rl.rate_table; } else if ((rl.flags & RT_IS_SELECTABLE) == RT_IS_SELECTABLE) { /* Chelsio, C5 and C6 of Mellanox? */ rs->rs_ifp = ifp; rs->rs_if_dunit = ifp->if_dunit; rs->rs_rate_cnt = rl.number_of_rates; rs->rs_min_seg = rl.min_segment_burst; rs->rs_disable = 0; rs->rs_flow_limit = rl.max_flows; rate_table_act = desired_rates; if ((rs->rs_rate_cnt > MAX_HDWR_RATES) && (rs->rs_rate_cnt < ALL_HARDWARE_RATES)) { /* * Our desired table is not big * enough, do what we can. */ rs->rs_rate_cnt = MAX_HDWR_RATES; } if (rs->rs_rate_cnt <= RS_ORDERED_COUNT) rs->rs_flags = RS_IS_INTF; else rs->rs_flags = RS_IS_INTF | RS_INT_TBL; if (rs->rs_rate_cnt >= ALL_HARDWARE_RATES) rs->rs_rate_cnt = ALL_HARDWARE_RATES; } else { free(rs, M_TCPPACE); return (NULL); } sz = sizeof(struct tcp_hwrate_limit_table) * rs->rs_rate_cnt; rs->rs_rlt = malloc(sz, M_TCPPACE, M_NOWAIT); if (rs->rs_rlt == NULL) { if (error) *error = ENOMEM; bail: free(rs, M_TCPPACE); return (NULL); } if (rs->rs_rate_cnt >= ALL_HARDWARE_RATES) { /* * The interface supports all * the rates we could possibly want. */ uint64_t rat; rs->rs_rlt[0].rate = 12500; /* 100k */ rs->rs_rlt[1].rate = 25000; /* 200k */ rs->rs_rlt[2].rate = 62500; /* 500k */ /* Note 125000 == 1Megabit * populate 1Meg - 1000meg. */ for(i = 3, rat = 125000; i< (ALL_HARDWARE_RATES-1); i++) { rs->rs_rlt[i].rate = rat; rat += 125000; } rs->rs_rlt[(ALL_HARDWARE_RATES-1)].rate = 1250000000; } else if (rs->rs_flags & RS_INT_TBL) { /* We populate this in a special way */ populate_canned_table(rs, rate_table_act); } else { /* * Just copy in the rates from * the table, it is in order. */ for (i=0; irs_rate_cnt; i++) { rs->rs_rlt[i].rate = rate_table_act[i]; rs->rs_rlt[i].time_between = 0; rs->rs_rlt[i].flags = 0; } } for (i = (rs->rs_rate_cnt - 1); i >= 0; i--) { /* * We go backwards through the list so that if we can't get * a rate and fail to init one, we have at least a chance of * getting the highest one. */ rs->rs_rlt[i].ptbl = rs; rs->rs_rlt[i].tag = NULL; rs->rs_rlt[i].using = 0; rs->rs_rlt[i].rs_num_enobufs = 0; /* * Calculate the time between. */ lentim = ETHERNET_SEGMENT_SIZE * USECS_IN_SECOND; res = lentim / rs->rs_rlt[i].rate; if (res > 0) rs->rs_rlt[i].time_between = res; else rs->rs_rlt[i].time_between = 1; if (rs->rs_flags & RS_NO_PRE) { rs->rs_rlt[i].flags = HDWRPACE_INITED; rs->rs_lowest_valid = i; } else { int err; if ((rl.flags & RT_IS_SETUP_REQ) && (ifp->if_ratelimit_query)) { err = ifp->if_ratelimit_setup(ifp, rs->rs_rlt[i].rate, i); if (err) goto handle_err; } #ifdef RSS hash_type = M_HASHTYPE_RSS_TCP_IPV4; #else hash_type = M_HASHTYPE_OPAQUE_HASH; #endif err = rl_attach_txrtlmt(ifp, hash_type, (i + 1), rs->rs_rlt[i].rate, &rs->rs_rlt[i].tag); if (err) { handle_err: if (i == (rs->rs_rate_cnt - 1)) { /* * Huh - first rate and we can't get * it? */ free(rs->rs_rlt, M_TCPPACE); if (error) *error = err; goto bail; } else { if (error) *error = err; } break; } else { rs->rs_rlt[i].flags = HDWRPACE_INITED | HDWRPACE_TAGPRESENT; rs->rs_lowest_valid = i; } } } /* Did we get at least 1 rate? */ if (rs->rs_rlt[(rs->rs_rate_cnt - 1)].flags & HDWRPACE_INITED) rs->rs_highest_valid = rs->rs_rate_cnt - 1; else { free(rs->rs_rlt, M_TCPPACE); goto bail; } rs_number_alive++; sysctl_ctx_init(&rs->sysctl_ctx); rl_sysctl_root = SYSCTL_ADD_NODE(&rs->sysctl_ctx, SYSCTL_STATIC_CHILDREN(_net_inet_tcp_rl), OID_AUTO, rs->rs_ifp->if_xname, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, ""); rl_add_syctl_entries(rl_sysctl_root, rs); NET_EPOCH_ENTER(et); mtx_lock(&rs_mtx); CK_LIST_INSERT_HEAD(&int_rs, rs, next); mtx_unlock(&rs_mtx); NET_EPOCH_EXIT(et); return (rs); } /* * For an explanation of why the argument is volatile please * look at the comments around rt_setup_rate(). */ static const struct tcp_hwrate_limit_table * tcp_int_find_suitable_rate(const volatile struct tcp_rate_set *rs, uint64_t bytes_per_sec, uint32_t flags, uint64_t *lower_rate) { struct tcp_hwrate_limit_table *arte = NULL, *rte = NULL; uint64_t mbits_per_sec, ind_calc, previous_rate = 0; int i; mbits_per_sec = (bytes_per_sec * 8); if (flags & RS_PACING_LT) { if ((mbits_per_sec < RS_ONE_MEGABIT_PERSEC) && (rs->rs_lowest_valid <= 2)){ /* * Smaller than 1Meg, only * 3 entries can match it. */ previous_rate = 0; for(i = rs->rs_lowest_valid; i < 3; i++) { if (bytes_per_sec <= rs->rs_rlt[i].rate) { rte = &rs->rs_rlt[i]; break; } else if (rs->rs_rlt[i].flags & HDWRPACE_INITED) { arte = &rs->rs_rlt[i]; } previous_rate = rs->rs_rlt[i].rate; } goto done; } else if ((mbits_per_sec > RS_ONE_GIGABIT_PERSEC) && (rs->rs_rlt[(ALL_HARDWARE_RATES-1)].flags & HDWRPACE_INITED)){ /* * Larger than 1G (the majority of * our table. */ if (mbits_per_sec < RS_TEN_GIGABIT_PERSEC) rte = &rs->rs_rlt[(ALL_HARDWARE_RATES-1)]; else arte = &rs->rs_rlt[(ALL_HARDWARE_RATES-1)]; previous_rate = rs->rs_rlt[(ALL_HARDWARE_RATES-2)].rate; goto done; } /* * If we reach here its in our table (between 1Meg - 1000Meg), * just take the rounded down mbits per second, and add * 1Megabit to it, from this we can calculate * the index in the table. */ ind_calc = mbits_per_sec/RS_ONE_MEGABIT_PERSEC; if ((ind_calc * RS_ONE_MEGABIT_PERSEC) != mbits_per_sec) ind_calc++; /* our table is offset by 3, we add 2 */ ind_calc += 2; if (ind_calc > (ALL_HARDWARE_RATES-1)) { /* This should not happen */ ind_calc = ALL_HARDWARE_RATES-1; } if ((ind_calc >= rs->rs_lowest_valid) && (ind_calc <= rs->rs_highest_valid)) { rte = &rs->rs_rlt[ind_calc]; if (ind_calc >= 1) previous_rate = rs->rs_rlt[(ind_calc-1)].rate; } } else if (flags & RS_PACING_EXACT_MATCH) { if ((mbits_per_sec < RS_ONE_MEGABIT_PERSEC) && (rs->rs_lowest_valid <= 2)){ for(i = rs->rs_lowest_valid; i < 3; i++) { if (bytes_per_sec == rs->rs_rlt[i].rate) { rte = &rs->rs_rlt[i]; break; } } } else if ((mbits_per_sec > RS_ONE_GIGABIT_PERSEC) && (rs->rs_rlt[(ALL_HARDWARE_RATES-1)].flags & HDWRPACE_INITED)) { /* > 1Gbps only one rate */ if (bytes_per_sec == rs->rs_rlt[(ALL_HARDWARE_RATES-1)].rate) { /* Its 10G wow */ rte = &rs->rs_rlt[(ALL_HARDWARE_RATES-1)]; } } else { /* Ok it must be a exact meg (its between 1G and 1Meg) */ ind_calc = mbits_per_sec/RS_ONE_MEGABIT_PERSEC; if ((ind_calc * RS_ONE_MEGABIT_PERSEC) == mbits_per_sec) { /* its an exact Mbps */ ind_calc += 2; if (ind_calc > (ALL_HARDWARE_RATES-1)) { /* This should not happen */ ind_calc = ALL_HARDWARE_RATES-1; } if (rs->rs_rlt[ind_calc].flags & HDWRPACE_INITED) rte = &rs->rs_rlt[ind_calc]; } } } else { /* we want greater than the requested rate */ if ((mbits_per_sec < RS_ONE_MEGABIT_PERSEC) && (rs->rs_lowest_valid <= 2)){ arte = &rs->rs_rlt[3]; /* set alternate to 1Meg */ for (i=2; i>=rs->rs_lowest_valid; i--) { if (bytes_per_sec < rs->rs_rlt[i].rate) { rte = &rs->rs_rlt[i]; if (i >= 1) { previous_rate = rs->rs_rlt[(i-1)].rate; } break; } else if ((flags & RS_PACING_GEQ) && (bytes_per_sec == rs->rs_rlt[i].rate)) { rte = &rs->rs_rlt[i]; if (i >= 1) { previous_rate = rs->rs_rlt[(i-1)].rate; } break; } else { arte = &rs->rs_rlt[i]; /* new alternate */ } } } else if (mbits_per_sec > RS_ONE_GIGABIT_PERSEC) { if ((bytes_per_sec < rs->rs_rlt[(ALL_HARDWARE_RATES-1)].rate) && (rs->rs_rlt[(ALL_HARDWARE_RATES-1)].flags & HDWRPACE_INITED)){ /* Our top rate is larger than the request */ rte = &rs->rs_rlt[(ALL_HARDWARE_RATES-1)]; } else if ((flags & RS_PACING_GEQ) && (bytes_per_sec == rs->rs_rlt[(ALL_HARDWARE_RATES-1)].rate) && (rs->rs_rlt[(ALL_HARDWARE_RATES-1)].flags & HDWRPACE_INITED)) { /* It matches our top rate */ rte = &rs->rs_rlt[(ALL_HARDWARE_RATES-1)]; } else if (rs->rs_rlt[(ALL_HARDWARE_RATES-1)].flags & HDWRPACE_INITED) { /* The top rate is an alternative */ arte = &rs->rs_rlt[(ALL_HARDWARE_RATES-1)]; } previous_rate = rs->rs_rlt[(ALL_HARDWARE_RATES-2)].rate; } else { /* Its in our range 1Meg - 1Gig */ if (flags & RS_PACING_GEQ) { ind_calc = mbits_per_sec/RS_ONE_MEGABIT_PERSEC; if ((ind_calc * RS_ONE_MEGABIT_PERSEC) == mbits_per_sec) { if (ind_calc > (ALL_HARDWARE_RATES-1)) { /* This should not happen */ ind_calc = (ALL_HARDWARE_RATES-1); } rte = &rs->rs_rlt[ind_calc]; if (ind_calc >= 1) previous_rate = rs->rs_rlt[(ind_calc-1)].rate; } goto done; } ind_calc = (mbits_per_sec + (RS_ONE_MEGABIT_PERSEC-1))/RS_ONE_MEGABIT_PERSEC; ind_calc += 2; if (ind_calc > (ALL_HARDWARE_RATES-1)) { /* This should not happen */ ind_calc = ALL_HARDWARE_RATES-1; } if (rs->rs_rlt[ind_calc].flags & HDWRPACE_INITED) { rte = &rs->rs_rlt[ind_calc]; if (ind_calc >= 1) previous_rate = rs->rs_rlt[(ind_calc-1)].rate; } } } done: if ((rte == NULL) && (arte != NULL) && (flags & RS_PACING_SUB_OK)) { /* We can use the substitute */ rte = arte; } if (lower_rate) *lower_rate = previous_rate; return (rte); } /* * For an explanation of why the argument is volatile please * look at the comments around rt_setup_rate(). */ static const struct tcp_hwrate_limit_table * tcp_find_suitable_rate(const volatile struct tcp_rate_set *rs, uint64_t bytes_per_sec, uint32_t flags, uint64_t *lower_rate) { /** * Hunt the rate table with the restrictions in flags and find a * suitable rate if possible. * RS_PACING_EXACT_MATCH - look for an exact match to rate. * RS_PACING_GT - must be greater than. * RS_PACING_GEQ - must be greater than or equal. * RS_PACING_LT - must be less than. * RS_PACING_SUB_OK - If we don't meet criteria a * substitute is ok. */ int i, matched; struct tcp_hwrate_limit_table *rte = NULL; uint64_t previous_rate = 0; if ((rs->rs_flags & RS_INT_TBL) && (rs->rs_rate_cnt >= ALL_HARDWARE_RATES)) { /* * Here we don't want to paw thru * a big table, we have everything * from 1Meg - 1000Meg in 1Meg increments. * Use an alternate method to "lookup". */ return (tcp_int_find_suitable_rate(rs, bytes_per_sec, flags, lower_rate)); } if ((flags & RS_PACING_LT) || (flags & RS_PACING_EXACT_MATCH)) { /* * For exact and less than we go forward through the table. * This way when we find one larger we stop (exact was a * toss up). */ for (i = rs->rs_lowest_valid, matched = 0; i <= rs->rs_highest_valid; i++) { if ((flags & RS_PACING_EXACT_MATCH) && (bytes_per_sec == rs->rs_rlt[i].rate)) { rte = &rs->rs_rlt[i]; matched = 1; if (lower_rate != NULL) *lower_rate = previous_rate; break; } else if ((flags & RS_PACING_LT) && (bytes_per_sec <= rs->rs_rlt[i].rate)) { rte = &rs->rs_rlt[i]; matched = 1; if (lower_rate != NULL) *lower_rate = previous_rate; break; } previous_rate = rs->rs_rlt[i].rate; if (bytes_per_sec > rs->rs_rlt[i].rate) break; } if ((matched == 0) && (flags & RS_PACING_LT) && (flags & RS_PACING_SUB_OK)) { /* Kick in a substitute (the lowest) */ rte = &rs->rs_rlt[rs->rs_lowest_valid]; } } else { /* * Here we go backward through the table so that we can find * the one greater in theory faster (but its probably a * wash). */ for (i = rs->rs_highest_valid, matched = 0; i >= rs->rs_lowest_valid; i--) { if (rs->rs_rlt[i].rate > bytes_per_sec) { /* A possible candidate */ rte = &rs->rs_rlt[i]; } if ((flags & RS_PACING_GEQ) && (bytes_per_sec == rs->rs_rlt[i].rate)) { /* An exact match and we want equal */ matched = 1; rte = &rs->rs_rlt[i]; break; } else if (rte) { /* * Found one that is larger than but don't * stop, there may be a more closer match. */ matched = 1; } if (rs->rs_rlt[i].rate < bytes_per_sec) { /* * We found a table entry that is smaller, * stop there will be none greater or equal. */ if (lower_rate != NULL) *lower_rate = rs->rs_rlt[i].rate; break; } } if ((matched == 0) && (flags & RS_PACING_SUB_OK)) { /* Kick in a substitute (the highest) */ rte = &rs->rs_rlt[rs->rs_highest_valid]; } } return (rte); } static struct ifnet * rt_find_real_interface(struct ifnet *ifp, struct inpcb *inp, int *error) { struct ifnet *tifp; struct m_snd_tag *tag, *ntag; union if_snd_tag_alloc_params params = { .rate_limit.hdr.type = IF_SND_TAG_TYPE_RATE_LIMIT, .rate_limit.hdr.flowid = inp->inp_flowid, .rate_limit.hdr.numa_domain = inp->inp_numa_domain, .rate_limit.max_rate = COMMON_RATE, .rate_limit.flags = M_NOWAIT, }; int err; #ifdef RSS params.rate_limit.hdr.flowtype = ((inp->inp_vflag & INP_IPV6) ? M_HASHTYPE_RSS_TCP_IPV6 : M_HASHTYPE_RSS_TCP_IPV4); #else params.rate_limit.hdr.flowtype = M_HASHTYPE_OPAQUE_HASH; #endif err = m_snd_tag_alloc(ifp, ¶ms, &tag); if (err) { /* Failed to setup a tag? */ if (error) *error = err; return (NULL); } ntag = tag; while (ntag->sw->next_snd_tag != NULL) { ntag = ntag->sw->next_snd_tag(ntag); } tifp = ntag->ifp; m_snd_tag_rele(tag); return (tifp); } static void rl_increment_using(const struct tcp_hwrate_limit_table *rte) { struct tcp_hwrate_limit_table *decon_rte; decon_rte = __DECONST(struct tcp_hwrate_limit_table *, rte); atomic_add_long(&decon_rte->using, 1); } static void rl_decrement_using(const struct tcp_hwrate_limit_table *rte) { struct tcp_hwrate_limit_table *decon_rte; decon_rte = __DECONST(struct tcp_hwrate_limit_table *, rte); atomic_subtract_long(&decon_rte->using, 1); } void tcp_rl_log_enobuf(const struct tcp_hwrate_limit_table *rte) { struct tcp_hwrate_limit_table *decon_rte; decon_rte = __DECONST(struct tcp_hwrate_limit_table *, rte); atomic_add_long(&decon_rte->rs_num_enobufs, 1); } /* * Do NOT take the __noinline out of the * find_rs_for_ifp() function. If you do the inline * of it for the rt_setup_rate() will show you a * compiler bug. For some reason the compiler thinks * the list can never be empty. The consequence of * this will be a crash when we dereference NULL * if an ifp is removed just has a hw rate limit * is attempted. If you are working on the compiler * and want to "test" this go ahead and take the noinline * out otherwise let sleeping dogs ly until such time * as we get a compiler fix 10/2/20 -- RRS */ static __noinline struct tcp_rate_set * find_rs_for_ifp(struct ifnet *ifp) { struct tcp_rate_set *rs; CK_LIST_FOREACH(rs, &int_rs, next) { if ((rs->rs_ifp == ifp) && (rs->rs_if_dunit == ifp->if_dunit)) { /* Ok we found it */ return (rs); } } return (NULL); } static const struct tcp_hwrate_limit_table * rt_setup_rate(struct inpcb *inp, struct ifnet *ifp, uint64_t bytes_per_sec, uint32_t flags, int *error, uint64_t *lower_rate) { /* First lets find the interface if it exists */ const struct tcp_hwrate_limit_table *rte; /* * So why is rs volatile? This is to defeat a * compiler bug where in the compiler is convinced * that rs can never be NULL (which is not true). Because * of its conviction it nicely optimizes out the if ((rs == NULL * below which means if you get a NULL back you dereference it. */ volatile struct tcp_rate_set *rs; struct epoch_tracker et; struct ifnet *oifp = ifp; int err; NET_EPOCH_ENTER(et); use_real_interface: rs = find_rs_for_ifp(ifp); if ((rs == NULL) || (rs->rs_flags & RS_INTF_NO_SUP) || (rs->rs_flags & RS_IS_DEAD)) { /* * This means we got a packet *before* * the IF-UP was processed below, * while or after we already received an interface * departed event. In either case we really don't * want to do anything with pacing, in * the departing case the packet is not * going to go very far. The new case * might be arguable, but its impossible * to tell from the departing case. */ if (error) *error = ENODEV; NET_EPOCH_EXIT(et); return (NULL); } if ((rs == NULL) || (rs->rs_disable != 0)) { if (error) *error = ENOSPC; NET_EPOCH_EXIT(et); return (NULL); } if (rs->rs_flags & RS_IS_DEFF) { /* We need to find the real interface */ struct ifnet *tifp; tifp = rt_find_real_interface(ifp, inp, error); if (tifp == NULL) { if (rs->rs_disable && error) *error = ENOTSUP; NET_EPOCH_EXIT(et); return (NULL); } KASSERT((tifp != ifp), ("Lookup failure ifp:%p inp:%p rt_find_real_interface() returns the same interface tifp:%p?\n", ifp, inp, tifp)); ifp = tifp; goto use_real_interface; } if (rs->rs_flow_limit && ((rs->rs_flows_using + 1) > rs->rs_flow_limit)) { if (error) *error = ENOSPC; NET_EPOCH_EXIT(et); return (NULL); } rte = tcp_find_suitable_rate(rs, bytes_per_sec, flags, lower_rate); if (rte) { err = in_pcbattach_txrtlmt(inp, oifp, inp->inp_flowtype, inp->inp_flowid, rte->rate, &inp->inp_snd_tag); if (err) { /* Failed to attach */ if (error) *error = err; rte = NULL; } else { KASSERT((inp->inp_snd_tag != NULL) , ("Setup rate has no snd_tag inp:%p rte:%p rate:%llu rs:%p", inp, rte, (unsigned long long)rte->rate, rs)); #ifdef INET counter_u64_add(rate_limit_new, 1); #endif } } if (rte) { /* * We use an atomic here for accounting so we don't have to * use locks when freeing. */ atomic_add_64(&rs->rs_flows_using, 1); } NET_EPOCH_EXIT(et); return (rte); } static void tcp_rl_ifnet_link(void *arg __unused, struct ifnet *ifp, int link_state) { int error; struct tcp_rate_set *rs; struct epoch_tracker et; if (((ifp->if_capenable & IFCAP_TXRTLMT) == 0) || (link_state != LINK_STATE_UP)) { /* * We only care on an interface going up that is rate-limit * capable. */ return; } NET_EPOCH_ENTER(et); mtx_lock(&rs_mtx); rs = find_rs_for_ifp(ifp); if (rs) { /* We already have initialized this guy */ mtx_unlock(&rs_mtx); NET_EPOCH_EXIT(et); return; } mtx_unlock(&rs_mtx); NET_EPOCH_EXIT(et); rt_setup_new_rs(ifp, &error); } static void tcp_rl_ifnet_departure(void *arg __unused, struct ifnet *ifp) { struct tcp_rate_set *rs; struct epoch_tracker et; int i; NET_EPOCH_ENTER(et); mtx_lock(&rs_mtx); rs = find_rs_for_ifp(ifp); if (rs) { CK_LIST_REMOVE(rs, next); rs_number_alive--; rs->rs_flags |= RS_IS_DEAD; for (i = 0; i < rs->rs_rate_cnt; i++) { if (rs->rs_rlt[i].flags & HDWRPACE_TAGPRESENT) { in_pcbdetach_tag(rs->rs_rlt[i].tag); rs->rs_rlt[i].tag = NULL; } rs->rs_rlt[i].flags = HDWRPACE_IFPDEPARTED; } if (rs->rs_flows_using == 0) rs_defer_destroy(rs); } mtx_unlock(&rs_mtx); NET_EPOCH_EXIT(et); } static void tcp_rl_shutdown(void *arg __unused, int howto __unused) { struct tcp_rate_set *rs, *nrs; struct epoch_tracker et; int i; NET_EPOCH_ENTER(et); mtx_lock(&rs_mtx); CK_LIST_FOREACH_SAFE(rs, &int_rs, next, nrs) { CK_LIST_REMOVE(rs, next); rs_number_alive--; rs->rs_flags |= RS_IS_DEAD; for (i = 0; i < rs->rs_rate_cnt; i++) { if (rs->rs_rlt[i].flags & HDWRPACE_TAGPRESENT) { in_pcbdetach_tag(rs->rs_rlt[i].tag); rs->rs_rlt[i].tag = NULL; } rs->rs_rlt[i].flags = HDWRPACE_IFPDEPARTED; } if (rs->rs_flows_using == 0) rs_defer_destroy(rs); } mtx_unlock(&rs_mtx); NET_EPOCH_EXIT(et); } const struct tcp_hwrate_limit_table * tcp_set_pacing_rate(struct tcpcb *tp, struct ifnet *ifp, uint64_t bytes_per_sec, int flags, int *error, uint64_t *lower_rate) { const struct tcp_hwrate_limit_table *rte; #ifdef KERN_TLS struct ktls_session *tls; #endif INP_WLOCK_ASSERT(tp->t_inpcb); if (tp->t_inpcb->inp_snd_tag == NULL) { /* * We are setting up a rate for the first time. */ if ((ifp->if_capenable & IFCAP_TXRTLMT) == 0) { /* Not supported by the egress */ if (error) *error = ENODEV; return (NULL); } #ifdef KERN_TLS tls = NULL; if (tp->t_inpcb->inp_socket->so_snd.sb_flags & SB_TLS_IFNET) { tls = tp->t_inpcb->inp_socket->so_snd.sb_tls_info; if ((ifp->if_capenable & IFCAP_TXTLS_RTLMT) == 0 || tls->mode != TCP_TLS_MODE_IFNET) { if (error) *error = ENODEV; return (NULL); } } #endif rte = rt_setup_rate(tp->t_inpcb, ifp, bytes_per_sec, flags, error, lower_rate); if (rte) rl_increment_using(rte); #ifdef KERN_TLS if (rte != NULL && tls != NULL && tls->snd_tag != NULL) { /* * Fake a route change error to reset the TLS * send tag. This will convert the existing * tag to a TLS ratelimit tag. */ MPASS(tls->snd_tag->sw->type == IF_SND_TAG_TYPE_TLS); ktls_output_eagain(tp->t_inpcb, tls); } #endif } else { /* * We are modifying a rate, wrong interface? */ if (error) *error = EINVAL; rte = NULL; } if (rte != NULL) { tp->t_pacing_rate = rte->rate; *error = 0; } return (rte); } const struct tcp_hwrate_limit_table * tcp_chg_pacing_rate(const struct tcp_hwrate_limit_table *crte, struct tcpcb *tp, struct ifnet *ifp, uint64_t bytes_per_sec, int flags, int *error, uint64_t *lower_rate) { const struct tcp_hwrate_limit_table *nrte; const struct tcp_rate_set *rs; #ifdef KERN_TLS struct ktls_session *tls = NULL; #endif int err; INP_WLOCK_ASSERT(tp->t_inpcb); if (crte == NULL) { /* Wrong interface */ if (error) *error = EINVAL; return (NULL); } #ifdef KERN_TLS if (tp->t_inpcb->inp_socket->so_snd.sb_flags & SB_TLS_IFNET) { tls = tp->t_inpcb->inp_socket->so_snd.sb_tls_info; MPASS(tls->mode == TCP_TLS_MODE_IFNET); if (tls->snd_tag != NULL && tls->snd_tag->sw->type != IF_SND_TAG_TYPE_TLS_RATE_LIMIT) { /* * NIC probably doesn't support ratelimit TLS * tags if it didn't allocate one when an * existing rate was present, so ignore. */ if (error) *error = EOPNOTSUPP; return (NULL); } } #endif if (tp->t_inpcb->inp_snd_tag == NULL) { /* Wrong interface */ if (error) *error = EINVAL; return (NULL); } rs = crte->ptbl; if ((rs->rs_flags & RS_IS_DEAD) || (crte->flags & HDWRPACE_IFPDEPARTED)) { /* Release the rate, and try anew */ tcp_rel_pacing_rate(crte, tp); nrte = tcp_set_pacing_rate(tp, ifp, bytes_per_sec, flags, error, lower_rate); return (nrte); } nrte = tcp_find_suitable_rate(rs, bytes_per_sec, flags, lower_rate); if (nrte == crte) { /* No change */ if (error) *error = 0; return (crte); } if (nrte == NULL) { /* Release the old rate */ if (error) *error = ENOENT; tcp_rel_pacing_rate(crte, tp); return (NULL); } rl_decrement_using(crte); rl_increment_using(nrte); /* Change rates to our new entry */ #ifdef KERN_TLS if (tls != NULL) err = ktls_modify_txrtlmt(tls, nrte->rate); else #endif err = in_pcbmodify_txrtlmt(tp->t_inpcb, nrte->rate); if (err) { rl_decrement_using(nrte); /* Do we still have a snd-tag attached? */ if (tp->t_inpcb->inp_snd_tag) in_pcbdetach_txrtlmt(tp->t_inpcb); if (error) *error = err; return (NULL); } else { #ifdef INET counter_u64_add(rate_limit_chg, 1); #endif } if (error) *error = 0; tp->t_pacing_rate = nrte->rate; return (nrte); } void tcp_rel_pacing_rate(const struct tcp_hwrate_limit_table *crte, struct tcpcb *tp) { const struct tcp_rate_set *crs; struct tcp_rate_set *rs; uint64_t pre; INP_WLOCK_ASSERT(tp->t_inpcb); tp->t_pacing_rate = -1; crs = crte->ptbl; /* * Now we must break the const * in order to release our refcount. */ rs = __DECONST(struct tcp_rate_set *, crs); rl_decrement_using(crte); pre = atomic_fetchadd_64(&rs->rs_flows_using, -1); if (pre == 1) { struct epoch_tracker et; NET_EPOCH_ENTER(et); mtx_lock(&rs_mtx); /* * Is it dead? */ if (rs->rs_flags & RS_IS_DEAD) rs_defer_destroy(rs); mtx_unlock(&rs_mtx); NET_EPOCH_EXIT(et); } /* * XXX: If this connection is using ifnet TLS, should we * switch it to using an unlimited rate, or perhaps use * ktls_output_eagain() to reset the send tag to a plain * TLS tag? */ in_pcbdetach_txrtlmt(tp->t_inpcb); } #define ONE_POINT_TWO_MEG 150000 /* 1.2 megabits in bytes */ #define ONE_HUNDRED_MBPS 12500000 /* 100Mbps in bytes per second */ #define FIVE_HUNDRED_MBPS 62500000 /* 500Mbps in bytes per second */ #define MAX_MSS_SENT 43 /* 43 mss = 43 x 1500 = 64,500 bytes */ static void tcp_log_pacing_size(struct tcpcb *tp, uint64_t bw, uint32_t segsiz, uint32_t new_tso, uint64_t hw_rate, uint32_t time_between, uint32_t calc_time_between, uint32_t segs, uint32_t res_div, uint16_t mult, uint8_t mod) { if (tp->t_logstate != TCP_LOG_STATE_OFF) { union tcp_log_stackspecific log; struct timeval tv; uint32_t cts; memset(&log, 0, sizeof(log)); cts = tcp_get_usecs(&tv); log.u_bbr.flex1 = segsiz; log.u_bbr.flex2 = new_tso; log.u_bbr.flex3 = time_between; log.u_bbr.flex4 = calc_time_between; log.u_bbr.flex5 = segs; log.u_bbr.flex6 = res_div; log.u_bbr.flex7 = mult; log.u_bbr.flex8 = mod; log.u_bbr.timeStamp = tcp_get_usecs(&tv); log.u_bbr.cur_del_rate = bw; log.u_bbr.delRate = hw_rate; TCP_LOG_EVENTP(tp, NULL, &tp->t_inpcb->inp_socket->so_rcv, &tp->t_inpcb->inp_socket->so_snd, TCP_HDWR_PACE_SIZE, 0, 0, &log, false, &tv); } } uint32_t tcp_get_pacing_burst_size (struct tcpcb *tp, uint64_t bw, uint32_t segsiz, int can_use_1mss, const struct tcp_hwrate_limit_table *te, int *err) { /* * We use the google formula to calculate the * TSO size. I.E. * bw < 24Meg * tso = 2mss * else * tso = min(bw/1000, 64k) * * Note for these calculations we ignore the * packet overhead (enet hdr, ip hdr and tcp hdr). */ uint64_t lentim, res, bytes; uint32_t new_tso, min_tso_segs; bytes = bw / 1000; if (bytes > (64 * 1000)) bytes = 64 * 1000; /* Round up */ new_tso = (bytes + segsiz - 1) / segsiz; if (can_use_1mss && (bw < ONE_POINT_TWO_MEG)) min_tso_segs = 1; else min_tso_segs = 2; if (rs_floor_mss && (new_tso < rs_floor_mss)) new_tso = rs_floor_mss; else if (new_tso < min_tso_segs) new_tso = min_tso_segs; if (new_tso > MAX_MSS_SENT) new_tso = MAX_MSS_SENT; new_tso *= segsiz; tcp_log_pacing_size(tp, bw, segsiz, new_tso, 0, 0, 0, 0, 0, 0, 1); /* * If we are not doing hardware pacing * then we are done. */ if (te == NULL) { if (err) *err = 0; return(new_tso); } /* * For hardware pacing we look at the * rate you are sending at and compare * that to the rate you have in hardware. * * If the hardware rate is slower than your * software rate then you are in error and * we will build a queue in our hardware whic * is probably not desired, in such a case * just return the non-hardware TSO size. * * If the rate in hardware is faster (which * it should be) then look at how long it * takes to send one ethernet segment size at * your b/w and compare that to the time it * takes to send at the rate you had selected. * * If your time is greater (which we hope it is) * we get the delta between the two, and then * divide that into your pacing time. This tells * us how many MSS you can send down at once (rounded up). * * Note we also double this value if the b/w is over * 100Mbps. If its over 500meg we just set you to the * max (43 segments). */ if (te->rate > FIVE_HUNDRED_MBPS) goto max; if (te->rate == bw) { /* We are pacing at exactly the hdwr rate */ max: tcp_log_pacing_size(tp, bw, segsiz, new_tso, te->rate, te->time_between, (uint32_t)0, (segsiz * MAX_MSS_SENT), 0, 0, 3); return (segsiz * MAX_MSS_SENT); } lentim = ETHERNET_SEGMENT_SIZE * USECS_IN_SECOND; res = lentim / bw; if (res > te->time_between) { uint32_t delta, segs, res_div; res_div = ((res * num_of_waits_allowed) + wait_time_floor); delta = res - te->time_between; segs = (res_div + delta - 1)/delta; if (segs < min_tso_segs) segs = min_tso_segs; if (segs < rs_hw_floor_mss) segs = rs_hw_floor_mss; if (segs > MAX_MSS_SENT) segs = MAX_MSS_SENT; segs *= segsiz; tcp_log_pacing_size(tp, bw, segsiz, new_tso, te->rate, te->time_between, (uint32_t)res, segs, res_div, 1, 3); if (err) *err = 0; if (segs < new_tso) { /* unexpected ? */ return(new_tso); } else { return (segs); } } else { /* * Your time is smaller which means * we will grow a queue on our * hardware. Send back the non-hardware * rate. */ tcp_log_pacing_size(tp, bw, segsiz, new_tso, te->rate, te->time_between, (uint32_t)res, 0, 0, 0, 4); if (err) *err = -1; return (new_tso); } } uint64_t tcp_hw_highest_rate_ifp(struct ifnet *ifp, struct inpcb *inp) { struct epoch_tracker et; struct tcp_rate_set *rs; uint64_t rate_ret; NET_EPOCH_ENTER(et); use_next_interface: rs = find_rs_for_ifp(ifp); if (rs == NULL) { /* This interface does not do ratelimiting */ rate_ret = 0; } else if (rs->rs_flags & RS_IS_DEFF) { /* We need to find the real interface */ struct ifnet *tifp; tifp = rt_find_real_interface(ifp, inp, NULL); if (tifp == NULL) { NET_EPOCH_EXIT(et); return (0); } ifp = tifp; goto use_next_interface; } else { /* Lets return the highest rate this guy has */ rate_ret = rs->rs_rlt[rs->rs_highest_valid].rate; } NET_EPOCH_EXIT(et); return(rate_ret); } static eventhandler_tag rl_ifnet_departs; static eventhandler_tag rl_ifnet_arrives; static eventhandler_tag rl_shutdown_start; static void tcp_rs_init(void *st __unused) { CK_LIST_INIT(&int_rs); rs_number_alive = 0; rs_number_dead = 0; mtx_init(&rs_mtx, "tcp_rs_mtx", "rsmtx", MTX_DEF); rl_ifnet_departs = EVENTHANDLER_REGISTER(ifnet_departure_event, tcp_rl_ifnet_departure, NULL, EVENTHANDLER_PRI_ANY); rl_ifnet_arrives = EVENTHANDLER_REGISTER(ifnet_link_event, tcp_rl_ifnet_link, NULL, EVENTHANDLER_PRI_ANY); rl_shutdown_start = EVENTHANDLER_REGISTER(shutdown_pre_sync, tcp_rl_shutdown, NULL, SHUTDOWN_PRI_FIRST); printf("TCP_ratelimit: Is now initialized\n"); } SYSINIT(tcp_rl_init, SI_SUB_SMP + 1, SI_ORDER_ANY, tcp_rs_init, NULL); #endif