tc/q_sfq.c

   1 /*
   2  * q_sfq.c              SFQ.
   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:     Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
  10  *
  11  */
  12
  13 #include <stdio.h>
  14 #include <stdlib.h>
  15 #include <unistd.h>
  16 #include <fcntl.h>
  17 #include <sys/socket.h>
  18 #include <netinet/in.h>
  19 #include <arpa/inet.h>
  20 #include <string.h>
  21 #include <math.h>
  22
  23 #include "utils.h"
  24 #include "tc_util.h"
  25 #include "tc_red.h"
  26
  27 static void explain(void)
  28 {
  29         fprintf(stderr, "Usage: ... sfq [ limit NUMBER ] [ perturb SECS ] [ quantum BYTES ]\n");
  30         fprintf(stderr, "               [ divisor NUMBER ] [ flows NUMBER] [ depth NUMBER ]\n");
  31         fprintf(stderr, "               [ headdrop ]\n");
  32         fprintf(stderr, "               [ redflowlimit BYTES ] [ min BYTES ] [ max BYTES ]\n");
  33         fprintf(stderr, "               [ avpkt BYTES ] [ burst PACKETS ] [ probability P ]\n");
  34         fprintf(stderr, "               [ ecn ] [ harddrop ]\n");
  35 }
  36
  37 static int sfq_parse_opt(struct qdisc_util *qu, int argc, char **argv, struct nlmsghdr *n, const char *dev)
  38 {
  39         int ok = 0, red = 0;
  40         struct tc_sfq_qopt_v1 opt = {};
  41         unsigned int burst = 0;
  42         int wlog;
  43         unsigned int avpkt = 1000;
  44         double probability = 0.02;
  45
  46         while (argc > 0) {
  47                 if (strcmp(*argv, "quantum") == 0) {
  48                         NEXT_ARG();
  49                         if (get_size(&opt.v0.quantum, *argv)) {
  50                                 fprintf(stderr, "Illegal \"limit\"\n");
  51                                 return -1;
  52                         }
  53                         ok++;
  54                 } else if (strcmp(*argv, "perturb") == 0) {
  55                         NEXT_ARG();
  56                         if (get_integer(&opt.v0.perturb_period, *argv, 0)) {
  57                                 fprintf(stderr, "Illegal \"perturb\"\n");
  58                                 return -1;
  59                         }
  60                         ok++;
  61                 } else if (strcmp(*argv, "limit") == 0) {
  62                         NEXT_ARG();
  63                         if (get_u32(&opt.v0.limit, *argv, 0)) {
  64                                 fprintf(stderr, "Illegal \"limit\"\n");
  65                                 return -1;
  66                         }
  67                         if (opt.v0.limit < 2) {
  68                                 fprintf(stderr, "Illegal \"limit\", must be > 1\n");
  69                                 return -1;
  70                         }
  71                         ok++;
  72                 } else if (strcmp(*argv, "divisor") == 0) {
  73                         NEXT_ARG();
  74                         if (get_u32(&opt.v0.divisor, *argv, 0)) {
  75                                 fprintf(stderr, "Illegal \"divisor\"\n");
  76                                 return -1;
  77                         }
  78                         ok++;
  79                 } else if (strcmp(*argv, "flows") == 0) {
  80                         NEXT_ARG();
  81                         if (get_u32(&opt.v0.flows, *argv, 0)) {
  82                                 fprintf(stderr, "Illegal \"flows\"\n");
  83                                 return -1;
  84                         }
  85                         ok++;
  86                 } else if (strcmp(*argv, "depth") == 0) {
  87                         NEXT_ARG();
  88                         if (get_u32(&opt.depth, *argv, 0)) {
  89                                 fprintf(stderr, "Illegal \"flows\"\n");
  90                                 return -1;
  91                         }
  92                         ok++;
  93                 } else if (strcmp(*argv, "headdrop") == 0) {
  94                         opt.headdrop = 1;
  95                         ok++;
  96                 } else if (strcmp(*argv, "redflowlimit") == 0) {
  97                         NEXT_ARG();
  98                         if (get_u32(&opt.limit, *argv, 0)) {
  99                                 fprintf(stderr, "Illegal \"redflowlimit\"\n");
 100                                 return -1;
 101                         }
 102                         red++;
 103                 } else if (strcmp(*argv, "min") == 0) {
 104                         NEXT_ARG();
 105                         if (get_u32(&opt.qth_min, *argv, 0)) {
 106                                 fprintf(stderr, "Illegal \"min\"\n");
 107                                 return -1;
 108                         }
 109                         red++;
 110                 } else if (strcmp(*argv, "max") == 0) {
 111                         NEXT_ARG();
 112                         if (get_u32(&opt.qth_max, *argv, 0)) {
 113                                 fprintf(stderr, "Illegal \"max\"\n");
 114                                 return -1;
 115                         }
 116                         red++;
 117                 } else if (strcmp(*argv, "burst") == 0) {
 118                         NEXT_ARG();
 119                         if (get_unsigned(&burst, *argv, 0)) {
 120                                 fprintf(stderr, "Illegal \"burst\"\n");
 121                                 return -1;
 122                         }
 123                         red++;
 124                 } else if (strcmp(*argv, "avpkt") == 0) {
 125                         NEXT_ARG();
 126                         if (get_size(&avpkt, *argv)) {
 127                                 fprintf(stderr, "Illegal \"avpkt\"\n");
 128                                 return -1;
 129                         }
 130                         red++;
 131                 } else if (strcmp(*argv, "probability") == 0) {
 132                         NEXT_ARG();
 133                         if (sscanf(*argv, "%lg", &probability) != 1) {
 134                                 fprintf(stderr, "Illegal \"probability\"\n");
 135                                 return -1;
 136                         }
 137                         red++;
 138                 } else if (strcmp(*argv, "ecn") == 0) {
 139                         opt.flags |= TC_RED_ECN;
 140                         red++;
 141                 } else if (strcmp(*argv, "harddrop") == 0) {
 142                         opt.flags |= TC_RED_HARDDROP;
 143                         red++;
 144                 } else if (strcmp(*argv, "help") == 0) {
 145                         explain();
 146                         return -1;
 147                 } else {
 148                         fprintf(stderr, "What is \"%s\"?\n", *argv);
 149                         explain();
 150                         return -1;
 151                 }
 152                 argc--; argv++;
 153         }
 154         if (red) {
 155                 if (!opt.limit) {
 156                         fprintf(stderr, "Required parameter (redflowlimit) is missing\n");
 157                         return -1;
 158                 }
 159                 /* Compute default min/max thresholds based on
 160                    Sally Floyd's recommendations:
 161                    http://www.icir.org/floyd/REDparameters.txt
 162                 */
 163                 if (!opt.qth_max)
 164                         opt.qth_max = opt.limit / 4;
 165                 if (!opt.qth_min)
 166                         opt.qth_min = opt.qth_max / 3;
 167                 if (!burst)
 168                         burst = (2 * opt.qth_min + opt.qth_max) / (3 * avpkt);
 169
 170                 if (opt.qth_max > opt.limit) {
 171                         fprintf(stderr, "\"max\" is larger than \"limit\"\n");
 172                         return -1;
 173                 }
 174
 175                 if (opt.qth_min >= opt.qth_max) {
 176                         fprintf(stderr, "\"min\" is not smaller than \"max\"\n");
 177                         return -1;
 178                 }
 179
 180                 wlog = tc_red_eval_ewma(opt.qth_min, burst, avpkt);
 181                 if (wlog < 0) {
 182                         fprintf(stderr, "SFQ: failed to calculate EWMA constant.\n");
 183                         return -1;
 184                 }
 185                 if (wlog >= 10)
 186                         fprintf(stderr, "SFQ: WARNING. Burst %u seems to be too large.\n", burst);
 187                 opt.Wlog = wlog;
 188
 189                 wlog = tc_red_eval_P(opt.qth_min, opt.qth_max, probability);
 190                 if (wlog < 0) {
 191                         fprintf(stderr, "SFQ: failed to calculate probability.\n");
 192                         return -1;
 193                 }
 194                 opt.Plog = wlog;
 195                 opt.max_P = probability * pow(2, 32);
 196         }
 197
 198         if (ok || red)
 199                 addattr_l(n, 1024, TCA_OPTIONS, &opt, sizeof(opt));
 200         return 0;
 201 }
 202
 203 static int sfq_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt)
 204 {
 205         struct tc_sfq_qopt *qopt;
 206         struct tc_sfq_qopt_v1 *qopt_ext = NULL;
 207
 208         SPRINT_BUF(b1);
 209         SPRINT_BUF(b2);
 210         SPRINT_BUF(b3);
 211         if (opt == NULL)
 212                 return 0;
 213
 214         if (RTA_PAYLOAD(opt)  < sizeof(*qopt))
 215                 return -1;
 216         if (RTA_PAYLOAD(opt) >= sizeof(*qopt_ext))
 217                 qopt_ext = RTA_DATA(opt);
 218         qopt = RTA_DATA(opt);
 219         fprintf(f, "limit %up ", qopt->limit);
 220         fprintf(f, "quantum %s ", sprint_size(qopt->quantum, b1));
 221         if (qopt_ext && qopt_ext->depth)
 222                 fprintf(f, "depth %u ", qopt_ext->depth);
 223         if (qopt_ext && qopt_ext->headdrop)
 224                 fprintf(f, "headdrop ");
 225
 226         if (show_details) {
 227                 fprintf(f, "flows %u/%u ", qopt->flows, qopt->divisor);
 228         }
 229         fprintf(f, "divisor %u ", qopt->divisor);
 230         if (qopt->perturb_period)
 231                 fprintf(f, "perturb %dsec ", qopt->perturb_period);
 232         if (qopt_ext && qopt_ext->qth_min) {
 233                 fprintf(f, "\n ewma %u ", qopt_ext->Wlog);
 234                 fprintf(f, "min %s max %s probability %g ",
 235                         sprint_size(qopt_ext->qth_min, b2),
 236                         sprint_size(qopt_ext->qth_max, b3),
 237                         qopt_ext->max_P / pow(2, 32));
 238                 if (qopt_ext->flags & TC_RED_ECN)
 239                         fprintf(f, "ecn ");
 240                 if (show_stats) {
 241                         fprintf(f, "\n prob_mark %u prob_mark_head %u prob_drop %u",
 242                                 qopt_ext->stats.prob_mark,
 243                                 qopt_ext->stats.prob_mark_head,
 244                                 qopt_ext->stats.prob_drop);
 245                         fprintf(f, "\n forced_mark %u forced_mark_head %u forced_drop %u",
 246                                 qopt_ext->stats.forced_mark,
 247                                 qopt_ext->stats.forced_mark_head,
 248                                 qopt_ext->stats.forced_drop);
 249                 }
 250         }
 251         return 0;
 252 }
 253
 254 static int sfq_print_xstats(struct qdisc_util *qu, FILE *f,
 255                             struct rtattr *xstats)
 256 {
 257         struct tc_sfq_xstats *st;
 258
 259         if (xstats == NULL)
 260                 return 0;
 261         if (RTA_PAYLOAD(xstats) < sizeof(*st))
 262                 return -1;
 263         st = RTA_DATA(xstats);
 264
 265         fprintf(f, " allot %d ", st->allot);
 266         fprintf(f, "\n");
 267         return 0;
 268 }
 269
 270 struct qdisc_util sfq_qdisc_util = {
 271         .id             = "sfq",
 272         .parse_qopt     = sfq_parse_opt,
 273         .print_qopt     = sfq_print_opt,
 274         .print_xstats   = sfq_print_xstats,
 275 };