tc/q_gred.c

   1 /*
   2  * q_gred.c             GRED.
   3  *
   4  *              This program is free software; you can redistribute it and/or
   5  *              modify it under the terms of the GNU General Public License
   6  *              as published by the Free Software Foundation; either version
   7  *              2 of the License, or (at your option) any later version.
   8  *
   9  * Authors:    J Hadi Salim(hadi@nortelnetworks.com)
  10  *             code ruthlessly ripped from
  11  *             Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
  12  *
  13  */
  14
  15 #include <stdio.h>
  16 #include <stdlib.h>
  17 #include <unistd.h>
  18 #include <fcntl.h>
  19 #include <sys/socket.h>
  20 #include <netinet/in.h>
  21 #include <arpa/inet.h>
  22 #include <string.h>
  23 #include <math.h>
  24
  25 #include "utils.h"
  26 #include "tc_util.h"
  27
  28 #include "tc_red.h"
  29
  30
  31 #if 0
  32 #define DPRINTF(format, args...) fprintf(stderr, format, ##args)
  33 #else
  34 #define DPRINTF(format, args...)
  35 #endif
  36
  37 static void explain(void)
  38 {
  39         fprintf(stderr, "Usage: tc qdisc { add | replace | change } ... gred setup vqs NUMBER\n");
  40         fprintf(stderr, "           default DEFAULT_VQ [ grio ] [ limit BYTES ]\n");
  41         fprintf(stderr, "       tc qdisc change ... gred vq VQ [ prio VALUE ] limit BYTES\n");
  42         fprintf(stderr, "           min BYTES max BYTES avpkt BYTES [ burst PACKETS ]\n");
  43         fprintf(stderr, "           [ probability PROBABILITY ] [ bandwidth KBPS ]\n");
  44 }
  45
  46 static int init_gred(struct qdisc_util *qu, int argc, char **argv,
  47                      struct nlmsghdr *n)
  48 {
  49
  50         struct rtattr *tail;
  51         struct tc_gred_sopt opt = { 0 };
  52         __u32 limit = 0;
  53
  54         opt.def_DP = MAX_DPs;
  55
  56         while (argc > 0) {
  57                 DPRINTF(stderr, "init_gred: invoked with %s\n", *argv);
  58                 if (strcmp(*argv, "vqs") == 0 ||
  59                     strcmp(*argv, "DPs") == 0) {
  60                         NEXT_ARG();
  61                         if (get_unsigned(&opt.DPs, *argv, 10)) {
  62                                 fprintf(stderr, "Illegal \"vqs\"\n");
  63                                 return -1;
  64                         } else if (opt.DPs > MAX_DPs) {
  65                                 fprintf(stderr, "GRED: only %u VQs are currently supported\n",
  66                                         MAX_DPs);
  67                                 return -1;
  68                         }
  69                 } else if (strcmp(*argv, "default") == 0) {
  70                         if (opt.DPs == 0) {
  71                                 fprintf(stderr, "\"default\" must be defined after \"vqs\"\n");
  72                                 return -1;
  73                         }
  74                         NEXT_ARG();
  75                         if (get_unsigned(&opt.def_DP, *argv, 10)) {
  76                                 fprintf(stderr, "Illegal \"default\"\n");
  77                                 return -1;
  78                         } else if (opt.def_DP >= opt.DPs) {
  79                                 fprintf(stderr, "\"default\" must be less than \"vqs\"\n");
  80                                 return -1;
  81                         }
  82                 } else if (strcmp(*argv, "grio") == 0) {
  83                         opt.grio = 1;
  84                 } else if (strcmp(*argv, "limit") == 0) {
  85                         NEXT_ARG();
  86                         if (get_size(&limit, *argv)) {
  87                                 fprintf(stderr, "Illegal \"limit\"\n");
  88                                 return -1;
  89                         }
  90                 } else if (strcmp(*argv, "help") == 0) {
  91                         explain();
  92                         return -1;
  93                 } else {
  94                         fprintf(stderr, "What is \"%s\"?\n", *argv);
  95                         explain();
  96                         return -1;
  97                 }
  98                 argc--; argv++;
  99         }
 100
 101         if (!opt.DPs || opt.def_DP == MAX_DPs) {
 102                 fprintf(stderr, "Illegal gred setup parameters\n");
 103                 return -1;
 104         }
 105
 106         DPRINTF("TC_GRED: sending DPs=%u def_DP=%u\n", opt.DPs, opt.def_DP);
 107         n->nlmsg_flags |= NLM_F_CREATE;
 108         tail = NLMSG_TAIL(n);
 109         addattr_l(n, 1024, TCA_OPTIONS, NULL, 0);
 110         addattr_l(n, 1024, TCA_GRED_DPS, &opt, sizeof(struct tc_gred_sopt));
 111         if (limit)
 112                 addattr32(n, 1024, TCA_GRED_LIMIT, limit);
 113         tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail;
 114         return 0;
 115 }
 116 /*
 117 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 118 */
 119 static int gred_parse_opt(struct qdisc_util *qu, int argc, char **argv, struct nlmsghdr *n)
 120 {
 121         int ok = 0;
 122         struct tc_gred_qopt opt = { 0 };
 123         unsigned int burst = 0;
 124         unsigned int avpkt = 0;
 125         double probability = 0.02;
 126         unsigned int rate = 0;
 127         int parm;
 128         __u8 sbuf[256];
 129         struct rtattr *tail;
 130         __u32 max_P;
 131
 132         opt.DP = MAX_DPs;
 133
 134         while (argc > 0) {
 135                 if (strcmp(*argv, "limit") == 0) {
 136                         NEXT_ARG();
 137                         if (get_size(&opt.limit, *argv)) {
 138                                 fprintf(stderr, "Illegal \"limit\"\n");
 139                                 return -1;
 140                         }
 141                         ok++;
 142                 } else if (strcmp(*argv, "setup") == 0) {
 143                         if (ok) {
 144                                 fprintf(stderr, "Illegal \"setup\"\n");
 145                                 return -1;
 146                         }
 147                         return init_gred(qu, argc-1, argv+1, n);
 148                 } else if (strcmp(*argv, "min") == 0) {
 149                         NEXT_ARG();
 150                         if (get_size(&opt.qth_min, *argv)) {
 151                                 fprintf(stderr, "Illegal \"min\"\n");
 152                                 return -1;
 153                         }
 154                         ok++;
 155                 } else if (strcmp(*argv, "max") == 0) {
 156                         NEXT_ARG();
 157                         if (get_size(&opt.qth_max, *argv)) {
 158                                 fprintf(stderr, "Illegal \"max\"\n");
 159                                 return -1;
 160                         }
 161                         ok++;
 162                 } else if (strcmp(*argv, "vq") == 0 ||
 163                            strcmp(*argv, "DP") == 0) {
 164                         NEXT_ARG();
 165                         if (get_unsigned(&opt.DP, *argv, 10)) {
 166                                 fprintf(stderr, "Illegal \"vq\"\n");
 167                                 return -1;
 168                         } else if (opt.DP >= MAX_DPs) {
 169                                 fprintf(stderr, "GRED: only %u VQs are currently supported\n",
 170                                         MAX_DPs);
 171                                 return -1;
 172                         } /* need a better error check */
 173                         ok++;
 174                 } else if (strcmp(*argv, "burst") == 0) {
 175                         NEXT_ARG();
 176                         if (get_unsigned(&burst, *argv, 0)) {
 177                                 fprintf(stderr, "Illegal \"burst\"\n");
 178                                 return -1;
 179                         }
 180                         ok++;
 181                 } else if (strcmp(*argv, "avpkt") == 0) {
 182                         NEXT_ARG();
 183                         if (get_size(&avpkt, *argv)) {
 184                                 fprintf(stderr, "Illegal \"avpkt\"\n");
 185                                 return -1;
 186                         }
 187                         ok++;
 188                 } else if (strcmp(*argv, "probability") == 0) {
 189                         NEXT_ARG();
 190                         if (sscanf(*argv, "%lg", &probability) != 1) {
 191                                 fprintf(stderr, "Illegal \"probability\"\n");
 192                                 return -1;
 193                         }
 194                         ok++;
 195                 } else if (strcmp(*argv, "prio") == 0) {
 196                         NEXT_ARG();
 197                         opt.prio = strtol(*argv, (char **)NULL, 10);
 198                         /* some error check here */
 199                         ok++;
 200                 } else if (strcmp(*argv, "bandwidth") == 0) {
 201                         NEXT_ARG();
 202                         if (get_rate(&rate, *argv)) {
 203                                 fprintf(stderr, "Illegal \"bandwidth\"\n");
 204                                 return -1;
 205                         }
 206                         ok++;
 207                 } else if (strcmp(*argv, "help") == 0) {
 208                         explain();
 209                         return -1;
 210                 } else {
 211                         fprintf(stderr, "What is \"%s\"?\n", *argv);
 212                         explain();
 213                         return -1;
 214                 }
 215                 argc--; argv++;
 216         }
 217
 218         if (!ok) {
 219                 explain();
 220                 return -1;
 221         }
 222         if (opt.DP == MAX_DPs || !opt.limit || !opt.qth_min || !opt.qth_max ||
 223             !avpkt) {
 224                 fprintf(stderr, "Required parameter (vq, limit, min, max, avpkt) is missing\n");
 225                 return -1;
 226         }
 227         if (!burst) {
 228                 burst = (2 * opt.qth_min + opt.qth_max) / (3 * avpkt);
 229                 fprintf(stderr, "GRED: set burst to %u\n", burst);
 230         }
 231         if (!rate) {
 232                 get_rate(&rate, "10Mbit");
 233                 fprintf(stderr, "GRED: set bandwidth to 10Mbit\n");
 234         }
 235         if ((parm = tc_red_eval_ewma(opt.qth_min, burst, avpkt)) < 0) {
 236                 fprintf(stderr, "GRED: failed to calculate EWMA constant.\n");
 237                 return -1;
 238         }
 239         if (parm >= 10)
 240                 fprintf(stderr, "GRED: WARNING. Burst %u seems to be too large.\n",
 241                     burst);
 242         opt.Wlog = parm;
 243         if ((parm = tc_red_eval_P(opt.qth_min, opt.qth_max, probability)) < 0) {
 244                 fprintf(stderr, "GRED: failed to calculate probability.\n");
 245                 return -1;
 246         }
 247         opt.Plog = parm;
 248         if ((parm = tc_red_eval_idle_damping(opt.Wlog, avpkt, rate, sbuf)) < 0)
 249             {
 250                 fprintf(stderr, "GRED: failed to calculate idle damping table.\n");
 251                 return -1;
 252         }
 253         opt.Scell_log = parm;
 254
 255         tail = NLMSG_TAIL(n);
 256         addattr_l(n, 1024, TCA_OPTIONS, NULL, 0);
 257         addattr_l(n, 1024, TCA_GRED_PARMS, &opt, sizeof(opt));
 258         addattr_l(n, 1024, TCA_GRED_STAB, sbuf, 256);
 259         max_P = probability * pow(2, 32);
 260         addattr32(n, 1024, TCA_GRED_MAX_P, max_P);
 261         tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail;
 262         return 0;
 263 }
 264
 265 static int gred_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt)
 266 {
 267         struct rtattr *tb[TCA_GRED_MAX + 1];
 268         struct tc_gred_sopt *sopt;
 269         struct tc_gred_qopt *qopt;
 270         __u32 *max_p = NULL;
 271         __u32 *limit = NULL;
 272         unsigned int i;
 273
 274         SPRINT_BUF(b1);
 275         SPRINT_BUF(b2);
 276         SPRINT_BUF(b3);
 277
 278         if (opt == NULL)
 279                 return 0;
 280
 281         parse_rtattr_nested(tb, TCA_GRED_MAX, opt);
 282
 283         if (tb[TCA_GRED_PARMS] == NULL)
 284                 return -1;
 285
 286         if (tb[TCA_GRED_MAX_P] &&
 287             RTA_PAYLOAD(tb[TCA_GRED_MAX_P]) >= sizeof(__u32) * MAX_DPs)
 288                 max_p = RTA_DATA(tb[TCA_GRED_MAX_P]);
 289
 290         if (tb[TCA_GRED_LIMIT] &&
 291             RTA_PAYLOAD(tb[TCA_GRED_LIMIT]) == sizeof(__u32))
 292                 limit = RTA_DATA(tb[TCA_GRED_LIMIT]);
 293
 294         sopt = RTA_DATA(tb[TCA_GRED_DPS]);
 295         qopt = RTA_DATA(tb[TCA_GRED_PARMS]);
 296         if (RTA_PAYLOAD(tb[TCA_GRED_DPS]) < sizeof(*sopt) ||
 297             RTA_PAYLOAD(tb[TCA_GRED_PARMS]) < sizeof(*qopt)*MAX_DPs) {
 298                 fprintf(f, "\n GRED received message smaller than expected\n");
 299                 return -1;
 300         }
 301
 302 /* Bad hack! should really return a proper message as shown above*/
 303
 304         fprintf(f, "vqs %u default %u %s",
 305                 sopt->DPs,
 306                 sopt->def_DP,
 307                 sopt->grio ? "grio " : "");
 308
 309         if (limit)
 310                 fprintf(f, "limit %s ",
 311                         sprint_size(*limit, b1));
 312
 313         for (i = 0; i < MAX_DPs; i++, qopt++) {
 314                 if (qopt->DP >= MAX_DPs) continue;
 315                 fprintf(f, "\n vq %u prio %hhu limit %s min %s max %s ",
 316                         qopt->DP,
 317                         qopt->prio,
 318                         sprint_size(qopt->limit, b1),
 319                         sprint_size(qopt->qth_min, b2),
 320                         sprint_size(qopt->qth_max, b3));
 321                 if (show_details) {
 322                         fprintf(f, "ewma %u ", qopt->Wlog);
 323                         if (max_p)
 324                                 fprintf(f, "probability %lg ", max_p[i] / pow(2, 32));
 325                         else
 326                                 fprintf(f, "Plog %u ", qopt->Plog);
 327                         fprintf(f, "Scell_log %u ", qopt->Scell_log);
 328                 }
 329                 if (show_stats) {
 330                         fprintf(f, "\n  Queue size: average %s current %s ",
 331                                 sprint_size(qopt->qave, b1),
 332                                 sprint_size(qopt->backlog, b2));
 333                         fprintf(f, "\n  Dropped packets: forced %u early %u pdrop %u other %u ",
 334                                 qopt->forced,
 335                                 qopt->early,
 336                                 qopt->pdrop,
 337                                 qopt->other);
 338                         fprintf(f, "\n  Total packets: %u (%s) ",
 339                                 qopt->packets,
 340                                 sprint_size(qopt->bytesin, b1));
 341                 }
 342         }
 343         return 0;
 344 }
 345
 346 struct qdisc_util gred_qdisc_util = {
 347         .id             = "gred",
 348         .parse_qopt     = gred_parse_opt,
 349         .print_qopt     = gred_print_opt,
 350 };