iproute2/tc/q_gred.c
Jakub Kicinski c8f201e3d2 tc: gred: remove unclear comment
The comment about providing a proper message seems similar to
the comment in the kernel which says:

    /* hack -- fix at some point with proper message
       This is how we indicate to tc that there is no VQ
       at this DP */

it's unclear what that message would be, and whether it's needed.
Remove the confusing comment.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
2018-11-24 07:08:16 -08:00

352 lines
9.0 KiB
C

/*
* q_gred.c GRED.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
* Authors: J Hadi Salim(hadi@nortelnetworks.com)
* code ruthlessly ripped from
* Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <string.h>
#include <math.h>
#include "utils.h"
#include "tc_util.h"
#include "tc_red.h"
#if 0
#define DPRINTF(format, args...) fprintf(stderr, format, ##args)
#else
#define DPRINTF(format, args...)
#endif
static void explain(void)
{
fprintf(stderr, "Usage: tc qdisc { add | replace | change } ... gred setup vqs NUMBER\n");
fprintf(stderr, " default DEFAULT_VQ [ grio ] [ limit BYTES ]\n");
fprintf(stderr, " tc qdisc change ... gred vq VQ [ prio VALUE ] limit BYTES\n");
fprintf(stderr, " min BYTES max BYTES avpkt BYTES [ burst PACKETS ]\n");
fprintf(stderr, " [ probability PROBABILITY ] [ bandwidth KBPS ]\n");
}
static int init_gred(struct qdisc_util *qu, int argc, char **argv,
struct nlmsghdr *n)
{
struct rtattr *tail;
struct tc_gred_sopt opt = { 0 };
__u32 limit = 0;
opt.def_DP = MAX_DPs;
while (argc > 0) {
DPRINTF(stderr, "init_gred: invoked with %s\n", *argv);
if (strcmp(*argv, "vqs") == 0 ||
strcmp(*argv, "DPs") == 0) {
NEXT_ARG();
if (get_unsigned(&opt.DPs, *argv, 10)) {
fprintf(stderr, "Illegal \"vqs\"\n");
return -1;
} else if (opt.DPs > MAX_DPs) {
fprintf(stderr, "GRED: only %u VQs are currently supported\n",
MAX_DPs);
return -1;
}
} else if (strcmp(*argv, "default") == 0) {
if (opt.DPs == 0) {
fprintf(stderr, "\"default\" must be defined after \"vqs\"\n");
return -1;
}
NEXT_ARG();
if (get_unsigned(&opt.def_DP, *argv, 10)) {
fprintf(stderr, "Illegal \"default\"\n");
return -1;
} else if (opt.def_DP >= opt.DPs) {
fprintf(stderr, "\"default\" must be less than \"vqs\"\n");
return -1;
}
} else if (strcmp(*argv, "grio") == 0) {
opt.grio = 1;
} else if (strcmp(*argv, "limit") == 0) {
NEXT_ARG();
if (get_size(&limit, *argv)) {
fprintf(stderr, "Illegal \"limit\"\n");
return -1;
}
} else if (strcmp(*argv, "help") == 0) {
explain();
return -1;
} else {
fprintf(stderr, "What is \"%s\"?\n", *argv);
explain();
return -1;
}
argc--; argv++;
}
if (!opt.DPs || opt.def_DP == MAX_DPs) {
fprintf(stderr, "Illegal gred setup parameters\n");
return -1;
}
DPRINTF("TC_GRED: sending DPs=%u def_DP=%u\n", opt.DPs, opt.def_DP);
n->nlmsg_flags |= NLM_F_CREATE;
tail = addattr_nest(n, 1024, TCA_OPTIONS);
addattr_l(n, 1024, TCA_GRED_DPS, &opt, sizeof(struct tc_gred_sopt));
if (limit)
addattr32(n, 1024, TCA_GRED_LIMIT, limit);
addattr_nest_end(n, tail);
return 0;
}
/*
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*/
static int gred_parse_opt(struct qdisc_util *qu, int argc, char **argv, struct nlmsghdr *n, const char *dev)
{
int ok = 0;
struct tc_gred_qopt opt = { 0 };
unsigned int burst = 0;
unsigned int avpkt = 0;
double probability = 0.02;
unsigned int rate = 0;
int parm;
__u8 sbuf[256];
struct rtattr *tail;
__u32 max_P;
opt.DP = MAX_DPs;
while (argc > 0) {
if (strcmp(*argv, "limit") == 0) {
NEXT_ARG();
if (get_size(&opt.limit, *argv)) {
fprintf(stderr, "Illegal \"limit\"\n");
return -1;
}
ok++;
} else if (strcmp(*argv, "setup") == 0) {
if (ok) {
fprintf(stderr, "Illegal \"setup\"\n");
return -1;
}
return init_gred(qu, argc-1, argv+1, n);
} else if (strcmp(*argv, "min") == 0) {
NEXT_ARG();
if (get_size(&opt.qth_min, *argv)) {
fprintf(stderr, "Illegal \"min\"\n");
return -1;
}
ok++;
} else if (strcmp(*argv, "max") == 0) {
NEXT_ARG();
if (get_size(&opt.qth_max, *argv)) {
fprintf(stderr, "Illegal \"max\"\n");
return -1;
}
ok++;
} else if (strcmp(*argv, "vq") == 0 ||
strcmp(*argv, "DP") == 0) {
NEXT_ARG();
if (get_unsigned(&opt.DP, *argv, 10)) {
fprintf(stderr, "Illegal \"vq\"\n");
return -1;
} else if (opt.DP >= MAX_DPs) {
fprintf(stderr, "GRED: only %u VQs are currently supported\n",
MAX_DPs);
return -1;
} /* need a better error check */
ok++;
} else if (strcmp(*argv, "burst") == 0) {
NEXT_ARG();
if (get_unsigned(&burst, *argv, 0)) {
fprintf(stderr, "Illegal \"burst\"\n");
return -1;
}
ok++;
} else if (strcmp(*argv, "avpkt") == 0) {
NEXT_ARG();
if (get_size(&avpkt, *argv)) {
fprintf(stderr, "Illegal \"avpkt\"\n");
return -1;
}
ok++;
} else if (strcmp(*argv, "probability") == 0) {
NEXT_ARG();
if (sscanf(*argv, "%lg", &probability) != 1) {
fprintf(stderr, "Illegal \"probability\"\n");
return -1;
}
ok++;
} else if (strcmp(*argv, "prio") == 0) {
NEXT_ARG();
opt.prio = strtol(*argv, (char **)NULL, 10);
/* some error check here */
ok++;
} else if (strcmp(*argv, "bandwidth") == 0) {
NEXT_ARG();
if (strchr(*argv, '%')) {
if (get_percent_rate(&rate, *argv, dev)) {
fprintf(stderr, "Illegal \"bandwidth\"\n");
return -1;
}
} else if (get_rate(&rate, *argv)) {
fprintf(stderr, "Illegal \"bandwidth\"\n");
return -1;
}
ok++;
} else if (strcmp(*argv, "help") == 0) {
explain();
return -1;
} else {
fprintf(stderr, "What is \"%s\"?\n", *argv);
explain();
return -1;
}
argc--; argv++;
}
if (!ok) {
explain();
return -1;
}
if (opt.DP == MAX_DPs || !opt.limit || !opt.qth_min || !opt.qth_max ||
!avpkt) {
fprintf(stderr, "Required parameter (vq, limit, min, max, avpkt) is missing\n");
return -1;
}
if (!burst) {
burst = (2 * opt.qth_min + opt.qth_max) / (3 * avpkt);
fprintf(stderr, "GRED: set burst to %u\n", burst);
}
if (!rate) {
get_rate(&rate, "10Mbit");
fprintf(stderr, "GRED: set bandwidth to 10Mbit\n");
}
if ((parm = tc_red_eval_ewma(opt.qth_min, burst, avpkt)) < 0) {
fprintf(stderr, "GRED: failed to calculate EWMA constant.\n");
return -1;
}
if (parm >= 10)
fprintf(stderr, "GRED: WARNING. Burst %u seems to be too large.\n",
burst);
opt.Wlog = parm;
if ((parm = tc_red_eval_P(opt.qth_min, opt.qth_max, probability)) < 0) {
fprintf(stderr, "GRED: failed to calculate probability.\n");
return -1;
}
opt.Plog = parm;
if ((parm = tc_red_eval_idle_damping(opt.Wlog, avpkt, rate, sbuf)) < 0)
{
fprintf(stderr, "GRED: failed to calculate idle damping table.\n");
return -1;
}
opt.Scell_log = parm;
tail = addattr_nest(n, 1024, TCA_OPTIONS);
addattr_l(n, 1024, TCA_GRED_PARMS, &opt, sizeof(opt));
addattr_l(n, 1024, TCA_GRED_STAB, sbuf, 256);
max_P = probability * pow(2, 32);
addattr32(n, 1024, TCA_GRED_MAX_P, max_P);
addattr_nest_end(n, tail);
return 0;
}
static int gred_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt)
{
struct rtattr *tb[TCA_GRED_MAX + 1];
struct tc_gred_sopt *sopt;
struct tc_gred_qopt *qopt;
__u32 *max_p = NULL;
__u32 *limit = NULL;
unsigned int i;
SPRINT_BUF(b1);
SPRINT_BUF(b2);
SPRINT_BUF(b3);
if (opt == NULL)
return 0;
parse_rtattr_nested(tb, TCA_GRED_MAX, opt);
if (tb[TCA_GRED_PARMS] == NULL)
return -1;
if (tb[TCA_GRED_MAX_P] &&
RTA_PAYLOAD(tb[TCA_GRED_MAX_P]) >= sizeof(__u32) * MAX_DPs)
max_p = RTA_DATA(tb[TCA_GRED_MAX_P]);
if (tb[TCA_GRED_LIMIT] &&
RTA_PAYLOAD(tb[TCA_GRED_LIMIT]) == sizeof(__u32))
limit = RTA_DATA(tb[TCA_GRED_LIMIT]);
sopt = RTA_DATA(tb[TCA_GRED_DPS]);
qopt = RTA_DATA(tb[TCA_GRED_PARMS]);
if (RTA_PAYLOAD(tb[TCA_GRED_DPS]) < sizeof(*sopt) ||
RTA_PAYLOAD(tb[TCA_GRED_PARMS]) < sizeof(*qopt)*MAX_DPs) {
fprintf(f, "\n GRED received message smaller than expected\n");
return -1;
}
fprintf(f, "vqs %u default %u %s",
sopt->DPs,
sopt->def_DP,
sopt->grio ? "grio " : "");
if (limit)
fprintf(f, "limit %s ",
sprint_size(*limit, b1));
for (i = 0; i < MAX_DPs; i++, qopt++) {
if (qopt->DP >= MAX_DPs) continue;
fprintf(f, "\n vq %u prio %hhu limit %s min %s max %s ",
qopt->DP,
qopt->prio,
sprint_size(qopt->limit, b1),
sprint_size(qopt->qth_min, b2),
sprint_size(qopt->qth_max, b3));
if (show_details) {
fprintf(f, "ewma %u ", qopt->Wlog);
if (max_p)
fprintf(f, "probability %lg ", max_p[i] / pow(2, 32));
else
fprintf(f, "Plog %u ", qopt->Plog);
fprintf(f, "Scell_log %u ", qopt->Scell_log);
}
if (show_stats) {
fprintf(f, "\n Queue size: average %s current %s ",
sprint_size(qopt->qave, b1),
sprint_size(qopt->backlog, b2));
fprintf(f, "\n Dropped packets: forced %u early %u pdrop %u other %u ",
qopt->forced,
qopt->early,
qopt->pdrop,
qopt->other);
fprintf(f, "\n Total packets: %u (%s) ",
qopt->packets,
sprint_size(qopt->bytesin, b1));
}
}
return 0;
}
struct qdisc_util gred_qdisc_util = {
.id = "gred",
.parse_qopt = gred_parse_opt,
.print_qopt = gred_print_opt,
};