[Codel] [PATCH] iproute2: added preliminary codel support
Dave Taht
dave.taht at gmail.com
Thu May 3 13:59:01 EDT 2012
I should have prepended 'RFC' to these two posts.
While this code compiles, and indeed lets you insert and use
the codel kernel module...
I appear to have goofed on the netlink implementation.
I get back:
!!!Deficit 20, rta_len=24
so I'm confused about the correct usage of the PARM parameter.
certainly a little code review from the more knowledgable
is highly desired. Or, I'll get back on it after a major nap.
On Thu, May 3, 2012 at 10:52 AM, Dave Täht <dave.taht at bufferbloat.net> wrote:
> this makes certain constants in the code variables, but
> has seemingly good defaults.
>
> target and interval can be specified with a ms, s, or us parameter
> mtu is in bytes
>
> ecn, while part of the api, is not enabled in the code
> ---
> include/linux/pkt_sched.h | 28 ++++++++++
> tc/Makefile | 1 +
> tc/q_codel.c | 135 +++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 164 insertions(+)
> create mode 100644 tc/q_codel.c
>
> diff --git a/include/linux/pkt_sched.h b/include/linux/pkt_sched.h
> index 410b33d..150aee9 100644
> --- a/include/linux/pkt_sched.h
> +++ b/include/linux/pkt_sched.h
> @@ -654,4 +654,32 @@ struct tc_qfq_stats {
> __u32 lmax;
> };
>
> +/* CODEL */
> +
> +enum {
> + TCA_CODEL_UNSPEC,
> + TCA_CODEL_PARMS,
> + TCA_CODEL_TARGET,
> + TCA_CODEL_DEPTH,
> + TCA_CODEL_MINBYTES,
> + TCA_CODEL_INTERVAL,
> + __TCA_CODEL_MAX
> +};
> +
> +#define TCA_CODEL_MAX (__TCA_CODEL_MAX - 1)
> +#define TC_CODEL_ECN 1
> +
> +struct tc_codel_qopt {
> + __u32 flags; /* flags (e.g. ecn) */
> + __u32 target; /* max delay, in us */
> + __u32 depth; /* queue depth in packets */
> + __u32 minbytes; /* MTU (usually) */
> + __u32 interval; /* Sliding min time window width (us) */
> +};
> +
> +struct tc_codel_stats {
> + __u64 drops;
> + __u64 marks;
> +};
> +
> #endif
> diff --git a/tc/Makefile b/tc/Makefile
> index be8cd5a..8a7cc8d 100644
> --- a/tc/Makefile
> +++ b/tc/Makefile
> @@ -47,6 +47,7 @@ TCMODULES += em_cmp.o
> TCMODULES += em_u32.o
> TCMODULES += em_meta.o
> TCMODULES += q_mqprio.o
> +TCMODULES += q_codel.o
>
> TCSO :=
> ifeq ($(TC_CONFIG_ATM),y)
> diff --git a/tc/q_codel.c b/tc/q_codel.c
> new file mode 100644
> index 0000000..2ff51a1
> --- /dev/null
> +++ b/tc/q_codel.c
> @@ -0,0 +1,135 @@
> +/*
> + * q_codel.c Controlled Delay
> + *
> + * 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: Dave Taht <d at taht.net>
> + *
> + */
> +
> +
> +
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <unistd.h>
> +#include <syslog.h>
> +#include <fcntl.h>
> +#include <sys/socket.h>
> +#include <netinet/in.h>
> +#include <arpa/inet.h>
> +#include <string.h>
> +
> +#include "utils.h"
> +#include "tc_util.h"
> +
> +static void explain(void)
> +{
> + fprintf(stderr,
> + "Usage: ... codel [target MAX_DELAY] [depth PACKETS]"
> + " [mtu MINBYTES]\n "
> + "[interval INTEGRATION_TIME] [ecn]\n" );
> +}
> +
> +static int codel_parse_opt(struct qdisc_util *qu, int argc, char **argv,
> + struct nlmsghdr *n)
> +{
> + struct tc_codel_qopt opt;
> + struct rtattr *tail;
> +
> + memset(&opt, 0, sizeof(opt));
> + opt.target = 5000;
> + opt.depth = 1000;
> + opt.interval = 1000*100;
> + opt.minbytes = 1500;
> + opt.flags = 0;
> +
> + while (argc > 0) {
> + if (strcmp(*argv, "target") == 0) {
> + NEXT_ARG();
> + if (get_time(&opt.target, *argv)) {
> + fprintf(stderr, "Illegal \"target\"\n");
> + return -1;
> + }
> + } else if (strcmp(*argv, "depth") == 0) {
> + NEXT_ARG();
> + if (get_u32(&opt.depth, *argv, 0)) {
> + fprintf(stderr, "Illegal \"depth\"\n");
> + return -1;
> + }
> + } else if (strcmp(*argv, "interval") == 0) {
> + NEXT_ARG();
> + if (get_time(&opt.interval, *argv)) {
> + fprintf(stderr, "Illegal \"interval\"\n");
> + return -1;
> + }
> + } else if (strcmp(*argv, "mtu") == 0) {
> + NEXT_ARG();
> + if (get_u32(&opt.minbytes, *argv, 0)) {
> + fprintf(stderr, "Illegal \"mtu\"\n");
> + return -1;
> + }
> + } else if (strcmp(*argv, "ecn") == 0) {
> + opt.flags |= TC_CODEL_ECN;
> + } else {
> + fprintf(stderr, "What is \"%s\"?\n", *argv);
> + explain();
> + return -1;
> + }
> + argc--; argv++;
> + }
> +
> + tail = NLMSG_TAIL(n);
> + addattr_l(n, 1024, TCA_OPTIONS, NULL, 0);
> + addattr_l(n, 1024, TCA_CODEL_PARMS, &opt, sizeof(opt));
> + tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail;
> + return 0;
> +}
> +
> +static int codel_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt)
> +{
> + struct rtattr *tb[__TCA_CODEL_MAX];
> + struct tc_codel_qopt *qopt;
> +
> + if (opt == NULL)
> + return 0;
> +
> + parse_rtattr_nested(tb, TCA_CODEL_MAX, opt);
> + if (tb[TCA_CODEL_PARMS] == NULL)
> + return -1;
> + qopt = RTA_DATA(tb[TCA_CODEL_PARMS]);
> + if (RTA_PAYLOAD(tb[TCA_CODEL_PARMS]) < sizeof(*qopt))
> + return -1;
> + fprintf(f," target %dus depth %d mtu %d interval %dus %s\n",
> + qopt->target, qopt->depth, qopt->minbytes,
> + qopt->interval, (qopt->flags & TC_CODEL_ECN) ? "ecn" : "");
> +
> + return 0;
> +}
> +
> +static int codel_print_xstats(struct qdisc_util *qu, FILE *f,
> + struct rtattr *xstats)
> +{
> + struct tc_codel_stats *st;
> +
> + if (xstats == NULL)
> + return 0;
> +
> + if (RTA_PAYLOAD(xstats) < sizeof(*st))
> + return -1;
> +
> + st = RTA_DATA(xstats);
> + fprintf(f, " dropped %lu marked %lu ",
> + st->drops, st->marks);
> +
> + return 0;
> +}
> +
> +struct qdisc_util codel_qdisc_util = {
> + .id = "codel",
> + .parse_qopt = codel_parse_opt,
> + .print_qopt = codel_print_opt,
> + .print_xstats = codel_print_xstats,
> +};
> --
> 1.7.9.5
>
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> Codel mailing list
> Codel at lists.bufferbloat.net
> https://lists.bufferbloat.net/listinfo/codel
--
Dave Täht
SKYPE: davetaht
US Tel: 1-239-829-5608
http://www.bufferbloat.net
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