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: ... gred DP drop-probability limit BYTES "
  41             "min BYTES max BYTES\n");
  42         fprintf(stderr, "    avpkt BYTES burst PACKETS probability PROBABILITY "
  43             "bandwidth KBPS\n");
  44         fprintf(stderr, "    [prio value]\n");
  45         fprintf(stderr," OR ...\n");
  46         fprintf(stderr," gred setup DPs <num of DPs> default <default DP> "
  47             "[grio]\n");
  48 }
  49
  50 static int init_gred(struct qdisc_util *qu, int argc, char **argv,
  51                      struct nlmsghdr *n)
  52 {
  53
  54         struct rtattr *tail;
  55         struct tc_gred_sopt opt = { 0 };
  56         int dps = 0;
  57         int def_dp = -1;
  58
  59         while (argc > 0) {
  60                 DPRINTF(stderr,"init_gred: invoked with %s\n",*argv);
  61                 if (strcmp(*argv, "DPs") == 0) {
  62                         NEXT_ARG();
  63                         DPRINTF(stderr,"init_gred: next_arg with %s\n",*argv);
  64                         dps = strtol(*argv, (char **)NULL, 10);
  65                         if (dps < 0 || dps >MAX_DPs) {
  66                                 fprintf(stderr, "DPs =%d\n", dps);
  67                                 fprintf(stderr, "Illegal \"DPs\"\n");
  68                                 fprintf(stderr, "GRED: only %d DPs are "
  69                                         "currently supported\n",MAX_DPs);
  70                                 return -1;
  71                         }
  72                 } else if (strcmp(*argv, "default") == 0) {
  73                         NEXT_ARG();
  74                         def_dp = strtol(*argv, (char **)NULL, 10);
  75                         if (dps == 0) {
  76                                 fprintf(stderr, "\"default DP\" must be "
  77                                         "defined after DPs\n");
  78                                 return -1;
  79                         }
  80                         if (def_dp < 0 || def_dp > dps) {
  81                                 fprintf(stderr,
  82                                         "\"default DP\" must be less than %d\n",
  83                                         opt.DPs);
  84                                 return -1;
  85                         }
  86                 } else if (strcmp(*argv, "grio") == 0) {
  87                         opt.grio = 1;
  88                 } else if (strcmp(*argv, "help") == 0) {
  89                         explain();
  90                         return -1;
  91                 } else {
  92                         fprintf(stderr, "What is \"%s\"?\n", *argv);
  93                         explain();
  94                         return -1;
  95                 }
  96                 argc--; argv++;
  97         }
  98
  99         if (!dps || def_dp == -1) {
 100                 fprintf(stderr, "Illegal gred setup parameters \n");
 101                 return -1;
 102         }
 103
 104         opt.DPs = dps;
 105         opt.def_DP = def_dp;
 106
 107         DPRINTF("TC_GRED: sending DPs=%d default=%d\n",opt.DPs,opt.def_DP);
 108         n->nlmsg_flags|=NLM_F_CREATE;
 109         tail = NLMSG_TAIL(n);
 110         addattr_l(n, 1024, TCA_OPTIONS, NULL, 0);
 111         addattr_l(n, 1024, TCA_GRED_DPS, &opt, sizeof(struct tc_gred_sopt));
 112         tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) 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)
 119 {
 120         int ok=0;
 121         struct tc_gred_qopt opt;
 122         unsigned burst = 0;
 123         unsigned avpkt = 0;
 124         double probability = 0.02;
 125         unsigned rate = 0;
 126         int wlog;
 127         __u8 sbuf[256];
 128         struct rtattr *tail;
 129         __u32 max_P;
 130
 131         memset(&opt, 0, sizeof(opt));
 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
 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, "DP") == 0) {
 163                         NEXT_ARG();
 164                         opt.DP=strtol(*argv, (char **)NULL, 10);
 165                         DPRINTF ("\n ******* DP =%u\n",opt.DP);
 166                         if (opt.DP >MAX_DPs) { /* need a better error check */
 167                                 fprintf(stderr, "DP =%u \n",opt.DP);
 168                                 fprintf(stderr, "Illegal \"DP\"\n");
 169                                 fprintf(stderr, "GRED: only %d DPs are currently supported\n",MAX_DPs);
 170                                 return -1;
 171                         }
 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 (get_rate(&rate, *argv)) {
 202                                 fprintf(stderr, "Illegal \"bandwidth\"\n");
 203                                 return -1;
 204                         }
 205                         ok++;
 206                 } else if (strcmp(*argv, "help") == 0) {
 207                         explain();
 208                         return -1;
 209                 } else {
 210                         fprintf(stderr, "What is \"%s\"?\n", *argv);
 211                         explain();
 212                         return -1;
 213                 }
 214                 argc--; argv++;
 215         }
 216
 217         if (rate == 0)
 218                 get_rate(&rate, "10Mbit");
 219
 220         if (!opt.qth_min || !opt.qth_max || !opt.limit || !avpkt ||
 221             (opt.DP<0)) {
 222                 fprintf(stderr, "Required parameter (min, max, limit, "
 223                     "avpkt, DP) is missing\n");
 224                 return -1;
 225         }
 226         if (!burst) {
 227                 burst = (2 * opt.qth_min + opt.qth_max) / (3 * avpkt);
 228                 fprintf(stderr, "GRED: set burst to %u\n", burst);
 229         }
 230
 231         if ((wlog = tc_red_eval_ewma(opt.qth_min, burst, avpkt)) < 0) {
 232                 fprintf(stderr, "GRED: failed to calculate EWMA constant.\n");
 233                 return -1;
 234         }
 235         if (wlog >= 10)
 236                 fprintf(stderr, "GRED: WARNING. Burst %d seems to be too "
 237                     "large.\n", burst);
 238         opt.Wlog = wlog;
 239         if ((wlog = tc_red_eval_P(opt.qth_min, opt.qth_max, probability)) < 0) {
 240                 fprintf(stderr, "GRED: failed to calculate probability.\n");
 241                 return -1;
 242         }
 243         opt.Plog = wlog;
 244         if ((wlog = tc_red_eval_idle_damping(opt.Wlog, avpkt, rate, sbuf)) < 0)
 245             {
 246                 fprintf(stderr, "GRED: failed to calculate idle damping "
 247                     "table.\n");
 248                 return -1;
 249         }
 250         opt.Scell_log = wlog;
 251
 252         tail = NLMSG_TAIL(n);
 253         addattr_l(n, 1024, TCA_OPTIONS, NULL, 0);
 254         addattr_l(n, 1024, TCA_GRED_PARMS, &opt, sizeof(opt));
 255         addattr_l(n, 1024, TCA_GRED_STAB, sbuf, 256);
 256         max_P = probability * pow(2, 32);
 257         addattr32(n, 1024, TCA_GRED_MAX_P, max_P);
 258         tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail;
 259         return 0;
 260 }
 261
 262 static int gred_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt)
 263 {
 264         struct rtattr *tb[TCA_GRED_MAX + 1];
 265         struct tc_gred_qopt *qopt;
 266         __u32 *max_p = NULL;
 267         int i;
 268         SPRINT_BUF(b1);
 269         SPRINT_BUF(b2);
 270         SPRINT_BUF(b3);
 271         SPRINT_BUF(b4);
 272         SPRINT_BUF(b5);
 273
 274         if (opt == NULL)
 275                 return 0;
 276
 277         parse_rtattr_nested(tb, TCA_GRED_MAX, opt);
 278
 279         if (tb[TCA_GRED_PARMS] == NULL)
 280                 return -1;
 281
 282         if (tb[TCA_GRED_MAX_P] &&
 283             RTA_PAYLOAD(tb[TCA_GRED_MAX_P]) >= sizeof(__u32) * MAX_DPs)
 284                 max_p = RTA_DATA(tb[TCA_GRED_MAX_P]);
 285
 286         qopt = RTA_DATA(tb[TCA_GRED_PARMS]);
 287         if (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         for (i=0;i<MAX_DPs;i++, qopt++) {
 295                 if (qopt->DP >= MAX_DPs) continue;
 296                 fprintf(f, "\n DP:%d (prio %d) Average Queue %s Measured "
 297                     "Queue %s  ",
 298                         qopt->DP,
 299                         qopt->prio,
 300                         sprint_size(qopt->qave, b4),
 301                         sprint_size(qopt->backlog, b5));
 302                 fprintf(f, "\n\t Packet drops: %d (forced %d early %d)  ",
 303                         qopt->forced+qopt->early,
 304                         qopt->forced,
 305                         qopt->early);
 306                 fprintf(f, "\n\t Packet totals: %u (bytes %u)  ",
 307                         qopt->packets,
 308                         qopt->bytesin);
 309                 if (show_details)
 310                         fprintf(f, "\n limit %s min %s max %s ",
 311                                 sprint_size(qopt->limit, b1),
 312                                 sprint_size(qopt->qth_min, b2),
 313                                 sprint_size(qopt->qth_max, b3));
 314                 fprintf(f, "ewma %u ", qopt->Wlog);
 315                 if (max_p)
 316                         fprintf(f, "probability %lg ", max_p[i] / pow(2, 32));
 317                 else
 318                         fprintf(f, "Plog %u ", qopt->Plog);
 319                 fprintf(f, "Scell_log %u", qopt->Scell_log);
 320         }
 321         return 0;
 322 }
 323
 324 struct qdisc_util gred_qdisc_util = {
 325         .id             = "gred",
 326         .parse_qopt     = gred_parse_opt,
 327         .print_qopt     = gred_print_opt,
 328 };