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 = addattr_nest(n, 1024, TCA_OPTIONS);
 109         addattr_l(n, 1024, TCA_GRED_DPS, &opt, sizeof(struct tc_gred_sopt));
 110         if (limit)
 111                 addattr32(n, 1024, TCA_GRED_LIMIT, limit);
 112         addattr_nest_end(n, tail);
 113         return 0;
 114 }
 115 /*
 116 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 117 */
 118 static int gred_parse_opt(struct qdisc_util *qu, int argc, char **argv, struct nlmsghdr *n, const char *dev)
 119 {
 120         int ok = 0;
 121         struct tc_gred_qopt opt = { 0 };
 122         unsigned int burst = 0;
 123         unsigned int avpkt = 0;
 124         double probability = 0.02;
 125         unsigned int rate = 0;
 126         int parm;
 127         __u8 sbuf[256];
 128         struct rtattr *tail;
 129         __u32 max_P;
 130
 131         opt.DP = MAX_DPs;
 132
 133         while (argc > 0) {
 134                 if (strcmp(*argv, "limit") == 0) {
 135                         NEXT_ARG();
 136                         if (get_size(&opt.limit, *argv)) {
 137                                 fprintf(stderr, "Illegal \"limit\"\n");
 138                                 return -1;
 139                         }
 140                         ok++;
 141                 } else if (strcmp(*argv, "setup") == 0) {
 142                         if (ok) {
 143                                 fprintf(stderr, "Illegal \"setup\"\n");
 144                                 return -1;
 145                         }
 146                         return init_gred(qu, argc-1, argv+1, n);
 147                 } else if (strcmp(*argv, "min") == 0) {
 148                         NEXT_ARG();
 149                         if (get_size(&opt.qth_min, *argv)) {
 150                                 fprintf(stderr, "Illegal \"min\"\n");
 151                                 return -1;
 152                         }
 153                         ok++;
 154                 } else if (strcmp(*argv, "max") == 0) {
 155                         NEXT_ARG();
 156                         if (get_size(&opt.qth_max, *argv)) {
 157                                 fprintf(stderr, "Illegal \"max\"\n");
 158                                 return -1;
 159                         }
 160                         ok++;
 161                 } else if (strcmp(*argv, "vq") == 0 ||
 162                            strcmp(*argv, "DP") == 0) {
 163                         NEXT_ARG();
 164                         if (get_unsigned(&opt.DP, *argv, 10)) {
 165                                 fprintf(stderr, "Illegal \"vq\"\n");
 166                                 return -1;
 167                         } else if (opt.DP >= MAX_DPs) {
 168                                 fprintf(stderr, "GRED: only %u VQs are currently supported\n",
 169                                         MAX_DPs);
 170                                 return -1;
 171                         } /* need a better error check */
 172                         ok++;
 173                 } else if (strcmp(*argv, "burst") == 0) {
 174                         NEXT_ARG();
 175                         if (get_unsigned(&burst, *argv, 0)) {
 176                                 fprintf(stderr, "Illegal \"burst\"\n");
 177                                 return -1;
 178                         }
 179                         ok++;
 180                 } else if (strcmp(*argv, "avpkt") == 0) {
 181                         NEXT_ARG();
 182                         if (get_size(&avpkt, *argv)) {
 183                                 fprintf(stderr, "Illegal \"avpkt\"\n");
 184                                 return -1;
 185                         }
 186                         ok++;
 187                 } else if (strcmp(*argv, "probability") == 0) {
 188                         NEXT_ARG();
 189                         if (sscanf(*argv, "%lg", &probability) != 1) {
 190                                 fprintf(stderr, "Illegal \"probability\"\n");
 191                                 return -1;
 192                         }
 193                         ok++;
 194                 } else if (strcmp(*argv, "prio") == 0) {
 195                         NEXT_ARG();
 196                         opt.prio = strtol(*argv, (char **)NULL, 10);
 197                         /* some error check here */
 198                         ok++;
 199                 } else if (strcmp(*argv, "bandwidth") == 0) {
 200                         NEXT_ARG();
 201                         if (strchr(*argv, '%')) {
 202                                 if (get_percent_rate(&rate, *argv, dev)) {
 203                                         fprintf(stderr, "Illegal \"bandwidth\"\n");
 204                                         return -1;
 205                                 }
 206                         } else if (get_rate(&rate, *argv)) {
 207                                 fprintf(stderr, "Illegal \"bandwidth\"\n");
 208                                 return -1;
 209                         }
 210                         ok++;
 211                 } else if (strcmp(*argv, "help") == 0) {
 212                         explain();
 213                         return -1;
 214                 } else {
 215                         fprintf(stderr, "What is \"%s\"?\n", *argv);
 216                         explain();
 217                         return -1;
 218                 }
 219                 argc--; argv++;
 220         }
 221
 222         if (!ok) {
 223                 explain();
 224                 return -1;
 225         }
 226         if (opt.DP == MAX_DPs || !opt.limit || !opt.qth_min || !opt.qth_max ||
 227             !avpkt) {
 228                 fprintf(stderr, "Required parameter (vq, limit, min, max, avpkt) is missing\n");
 229                 return -1;
 230         }
 231         if (!burst) {
 232                 burst = (2 * opt.qth_min + opt.qth_max) / (3 * avpkt);
 233                 fprintf(stderr, "GRED: set burst to %u\n", burst);
 234         }
 235         if (!rate) {
 236                 get_rate(&rate, "10Mbit");
 237                 fprintf(stderr, "GRED: set bandwidth to 10Mbit\n");
 238         }
 239         if ((parm = tc_red_eval_ewma(opt.qth_min, burst, avpkt)) < 0) {
 240                 fprintf(stderr, "GRED: failed to calculate EWMA constant.\n");
 241                 return -1;
 242         }
 243         if (parm >= 10)
 244                 fprintf(stderr, "GRED: WARNING. Burst %u seems to be too large.\n",
 245                     burst);
 246         opt.Wlog = parm;
 247         if ((parm = tc_red_eval_P(opt.qth_min, opt.qth_max, probability)) < 0) {
 248                 fprintf(stderr, "GRED: failed to calculate probability.\n");
 249                 return -1;
 250         }
 251         opt.Plog = parm;
 252         if ((parm = tc_red_eval_idle_damping(opt.Wlog, avpkt, rate, sbuf)) < 0)
 253             {
 254                 fprintf(stderr, "GRED: failed to calculate idle damping table.\n");
 255                 return -1;
 256         }
 257         opt.Scell_log = parm;
 258
 259         tail = addattr_nest(n, 1024, TCA_OPTIONS);
 260         addattr_l(n, 1024, TCA_GRED_PARMS, &opt, sizeof(opt));
 261         addattr_l(n, 1024, TCA_GRED_STAB, sbuf, 256);
 262         max_P = probability * pow(2, 32);
 263         addattr32(n, 1024, TCA_GRED_MAX_P, max_P);
 264         addattr_nest_end(n, tail);
 265         return 0;
 266 }
 267
 268 static int gred_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt)
 269 {
 270         struct rtattr *tb[TCA_GRED_MAX + 1];
 271         struct tc_gred_sopt *sopt;
 272         struct tc_gred_qopt *qopt;
 273         __u32 *max_p = NULL;
 274         __u32 *limit = NULL;
 275         unsigned int i;
 276
 277         SPRINT_BUF(b1);
 278         SPRINT_BUF(b2);
 279         SPRINT_BUF(b3);
 280
 281         if (opt == NULL)
 282                 return 0;
 283
 284         parse_rtattr_nested(tb, TCA_GRED_MAX, opt);
 285
 286         if (tb[TCA_GRED_PARMS] == NULL)
 287                 return -1;
 288
 289         if (tb[TCA_GRED_MAX_P] &&
 290             RTA_PAYLOAD(tb[TCA_GRED_MAX_P]) >= sizeof(__u32) * MAX_DPs)
 291                 max_p = RTA_DATA(tb[TCA_GRED_MAX_P]);
 292
 293         if (tb[TCA_GRED_LIMIT] &&
 294             RTA_PAYLOAD(tb[TCA_GRED_LIMIT]) == sizeof(__u32))
 295                 limit = RTA_DATA(tb[TCA_GRED_LIMIT]);
 296
 297         sopt = RTA_DATA(tb[TCA_GRED_DPS]);
 298         qopt = RTA_DATA(tb[TCA_GRED_PARMS]);
 299         if (RTA_PAYLOAD(tb[TCA_GRED_DPS]) < sizeof(*sopt) ||
 300             RTA_PAYLOAD(tb[TCA_GRED_PARMS]) < sizeof(*qopt)*MAX_DPs) {
 301                 fprintf(f, "\n GRED received message smaller than expected\n");
 302                 return -1;
 303         }
 304
 305 /* Bad hack! should really return a proper message as shown above*/
 306
 307         fprintf(f, "vqs %u default %u %s",
 308                 sopt->DPs,
 309                 sopt->def_DP,
 310                 sopt->grio ? "grio " : "");
 311
 312         if (limit)
 313                 fprintf(f, "limit %s ",
 314                         sprint_size(*limit, b1));
 315
 316         for (i = 0; i < MAX_DPs; i++, qopt++) {
 317                 if (qopt->DP >= MAX_DPs) continue;
 318                 fprintf(f, "\n vq %u prio %hhu limit %s min %s max %s ",
 319                         qopt->DP,
 320                         qopt->prio,
 321                         sprint_size(qopt->limit, b1),
 322                         sprint_size(qopt->qth_min, b2),
 323                         sprint_size(qopt->qth_max, b3));
 324                 if (show_details) {
 325                         fprintf(f, "ewma %u ", qopt->Wlog);
 326                         if (max_p)
 327                                 fprintf(f, "probability %lg ", max_p[i] / pow(2, 32));
 328                         else
 329                                 fprintf(f, "Plog %u ", qopt->Plog);
 330                         fprintf(f, "Scell_log %u ", qopt->Scell_log);
 331                 }
 332                 if (show_stats) {
 333                         fprintf(f, "\n  Queue size: average %s current %s ",
 334                                 sprint_size(qopt->qave, b1),
 335                                 sprint_size(qopt->backlog, b2));
 336                         fprintf(f, "\n  Dropped packets: forced %u early %u pdrop %u other %u ",
 337                                 qopt->forced,
 338                                 qopt->early,
 339                                 qopt->pdrop,
 340                                 qopt->other);
 341                         fprintf(f, "\n  Total packets: %u (%s) ",
 342                                 qopt->packets,
 343                                 sprint_size(qopt->bytesin, b1));
 344                 }
 345         }
 346         return 0;
 347 }
 348
 349 struct qdisc_util gred_qdisc_util = {
 350         .id             = "gred",
 351         .parse_qopt     = gred_parse_opt,
 352         .print_qopt     = gred_print_opt,
 353 };