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