From 837c38c3365b63ba486d0b0eb8a963621d8f0ac2 Mon Sep 17 00:00:00 2001

From: Eric Dumazet <edumazet@google.com>

Date: Thu, 29 Aug 2013 19:30:36 -0700

Subject: [PATCH 1/2] pkt_sched: fq: Fair Queue packet scheduler

Support for FQ packet scheduler

$ tc qd add dev eth0 root fq help

Usage: ... fq [ limit PACKETS ] [ flow_limit PACKETS ]

              [ quantum BYTES ] [ initial_quantum BYTES ]

              [ maxrate RATE  ] [ buckets NUMBER ]

              [ [no]pacing ]

$ tc -s -d qd

qdisc fq 8002: dev eth0 root refcnt 32 limit 10000p flow_limit 100p

buckets 256 quantum 3028 initial_quantum 15140

 Sent 216532416 bytes 148395 pkt (dropped 0, overlimits 0 requeues 14)

 backlog 0b 0p requeues 14

  511 flows (511 inactive, 0 throttled)

  110 gc, 0 highprio, 0 retrans, 1143 throttled, 0 flows_plimit

limit	: max number of packets on whole Qdisc (default 10000)

flow_limit : max number of packets per flow (default 100)

quantum : the max deficit per RR round (default is 2 MTU)

initial_quantum : initial credit for new flows (default is 10 MTU)

maxrate : max per flow rate (default : unlimited)

buckets : number of RB trees (default : 1024) in hash table.

               (consumes 8 bytes per bucket)

[no]pacing : disable/enable pacing (default is enable)

Usage :

tc qdisc add dev $ETH root fq

tc qdisc del dev $ETH root 2>/dev/null

tc qdisc add dev $ETH root handle 1: mq

for i in `seq 1 4`

do

  tc qdisc add dev $ETH parent 1:$i est 1sec 4sec fq

done

Signed-off-by: Eric Dumazet <edumazet@google.com>

---

 tc/Makefile |   1 +

 tc/q_fq.c   | 279 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

 2 files changed, 280 insertions(+)

 create mode 100644 tc/q_fq.c

diff --git a/tc/Makefile b/tc/Makefile

index af6a277..79116f3 100644

--- a/tc/Makefile

+++ b/tc/Makefile

@@ -56,6 +56,7 @@ TCMODULES += em_meta.o

 TCMODULES += q_mqprio.o

 TCMODULES += q_codel.o

 TCMODULES += q_fq_codel.o

+TCMODULES += q_fq.o

 ifeq ($(TC_CONFIG_IPSET), y)

   ifeq ($(TC_CONFIG_XT), y)

diff --git a/tc/q_fq.c b/tc/q_fq.c

new file mode 100644

index 0000000..c1f658e

--- /dev/null

+++ b/tc/q_fq.c

@@ -0,0 +1,279 @@

+/*

+ * Fair Queue

+ *

+ *  Copyright (C) 2013 Eric Dumazet <edumazet@google.com>

+ *

+ * Redistribution and use in source and binary forms, with or without

+ * modification, are permitted provided that the following conditions

+ * are met:

+ * 1. Redistributions of source code must retain the above copyright

+ *    notice, this list of conditions, and the following disclaimer,

+ *    without modification.

+ * 2. Redistributions in binary form must reproduce the above copyright

+ *    notice, this list of conditions and the following disclaimer in the

+ *    documentation and/or other materials provided with the distribution.

+ * 3. The names of the authors may not be used to endorse or promote products

+ *    derived from this software without specific prior written permission.

+ *

+ * Alternatively, provided that this notice is retained in full, this

+ * software may be distributed under the terms of the GNU General

+ * Public License ("GPL") version 2, in which case the provisions of the

+ * GPL apply INSTEAD OF those given above.

+ *

+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR

+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT

+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH

+ * DAMAGE.

+ *

+ */

+

+#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: ... fq [ limit PACKETS ] [ flow_limit PACKETS ]\n");

+	fprintf(stderr, "              [ quantum BYTES ] [ initial_quantum BYTES ]\n");

+	fprintf(stderr, "              [ maxrate RATE  ] [ buckets NUMBER ]\n");

+	fprintf(stderr, "              [ [no]pacing ]\n");

+}

+

+static unsigned int ilog2(unsigned int val)

+{

+	unsigned int res = 0;

+

+	val--;

+	while (val) {

+		res++;

+		val >>= 1;

+	}

+	return res;

+}

+

+static int fq_parse_opt(struct qdisc_util *qu, int argc, char **argv,

+			struct nlmsghdr *n)

+{

+	unsigned int plimit = ~0U;

+	unsigned int flow_plimit = ~0U;

+	unsigned int quantum = ~0U;

+	unsigned int initial_quantum = ~0U;

+	unsigned int buckets = 0;

+	unsigned int maxrate = ~0U;

+	unsigned int defrate = ~0U;

+	int pacing = -1;

+	struct rtattr *tail;

+

+	while (argc > 0) {

+		if (strcmp(*argv, "limit") == 0) {

+			NEXT_ARG();

+			if (get_unsigned(&plimit, *argv, 0)) {

+				fprintf(stderr, "Illegal \"limit\"\n");

+				return -1;

+			}

+		} else if (strcmp(*argv, "flow_limit") == 0) {

+			NEXT_ARG();

+			if (get_unsigned(&flow_plimit, *argv, 0)) {

+				fprintf(stderr, "Illegal \"flow_limit\"\n");

+				return -1;

+			}

+		} else if (strcmp(*argv, "buckets") == 0) {

+			NEXT_ARG();

+			if (get_unsigned(&buckets, *argv, 0)) {

+				fprintf(stderr, "Illegal \"buckets\"\n");

+				return -1;

+			}

+		} else if (strcmp(*argv, "maxrate") == 0) {

+			NEXT_ARG();

+			if (get_rate(&maxrate, *argv)) {

+				fprintf(stderr, "Illegal \"maxrate\"\n");

+				return -1;

+			}

+		} else if (strcmp(*argv, "defrate") == 0) {

+			NEXT_ARG();

+			if (get_rate(&defrate, *argv)) {

+				fprintf(stderr, "Illegal \"defrate\"\n");

+				return -1;

+			}

+		} else if (strcmp(*argv, "quantum") == 0) {

+			NEXT_ARG();

+			if (get_unsigned(&quantum, *argv, 0)) {

+				fprintf(stderr, "Illegal \"quantum\"\n");

+				return -1;

+			}

+		} else if (strcmp(*argv, "initial_quantum") == 0) {

+			NEXT_ARG();

+			if (get_unsigned(&initial_quantum, *argv, 0)) {

+				fprintf(stderr, "Illegal \"initial_quantum\"\n");

+				return -1;

+			}

+		} else if (strcmp(*argv, "pacing") == 0) {

+			pacing = 1;

+		} else if (strcmp(*argv, "nopacing") == 0) {

+			pacing = 0;

+		} else if (strcmp(*argv, "help") == 0) {

+			explain();

+			return -1;

+		} 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);

+	if (buckets) {

+		unsigned int log = ilog2(buckets);

+

+		addattr_l(n, 1024, TCA_FQ_BUCKETS_LOG,

+			  &log, sizeof(log));

+	}

+	if (plimit != ~0U)

+		addattr_l(n, 1024, TCA_FQ_PLIMIT,

+			  &plimit, sizeof(plimit));

+	if (flow_plimit != ~0U)

+		addattr_l(n, 1024, TCA_FQ_FLOW_PLIMIT,

+			  &flow_plimit, sizeof(flow_plimit));

+	if (quantum != ~0U)

+		addattr_l(n, 1024, TCA_FQ_QUANTUM, &quantum, sizeof(quantum));

+	if (initial_quantum != ~0U)

+		addattr_l(n, 1024, TCA_FQ_INITIAL_QUANTUM,

+			  &initial_quantum, sizeof(initial_quantum));

+	if (pacing != -1)

+		addattr_l(n, 1024, TCA_FQ_RATE_ENABLE,

+			  &pacing, sizeof(pacing));

+	if (maxrate != ~0U)

+		addattr_l(n, 1024, TCA_FQ_FLOW_MAX_RATE,

+			  &maxrate, sizeof(maxrate));

+	if (defrate != ~0U)

+		addattr_l(n, 1024, TCA_FQ_FLOW_DEFAULT_RATE,

+			  &defrate, sizeof(defrate));

+	tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail;

+	return 0;

+}

+

+static int fq_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt)

+{

+	struct rtattr *tb[TCA_FQ_MAX + 1];

+	unsigned int plimit, flow_plimit;

+	unsigned int buckets_log;

+	int pacing;

+	unsigned int rate, quantum;

+	SPRINT_BUF(b1);

+

+	if (opt == NULL)

+		return 0;

+

+	parse_rtattr_nested(tb, TCA_FQ_MAX, opt);

+

+	if (tb[TCA_FQ_PLIMIT] &&

+	    RTA_PAYLOAD(tb[TCA_FQ_PLIMIT]) >= sizeof(__u32)) {

+		plimit = rta_getattr_u32(tb[TCA_FQ_PLIMIT]);

+		fprintf(f, "limit %up ", plimit);

+	}

+	if (tb[TCA_FQ_FLOW_PLIMIT] &&

+	    RTA_PAYLOAD(tb[TCA_FQ_FLOW_PLIMIT]) >= sizeof(__u32)) {

+		flow_plimit = rta_getattr_u32(tb[TCA_FQ_FLOW_PLIMIT]);

+		fprintf(f, "flow_limit %up ", flow_plimit);

+	}

+	if (tb[TCA_FQ_BUCKETS_LOG] &&

+	    RTA_PAYLOAD(tb[TCA_FQ_BUCKETS_LOG]) >= sizeof(__u32)) {

+		buckets_log = rta_getattr_u32(tb[TCA_FQ_BUCKETS_LOG]);

+		fprintf(f, "buckets %u ", 1U << buckets_log);

+	}

+	if (tb[TCA_FQ_RATE_ENABLE] &&

+	    RTA_PAYLOAD(tb[TCA_FQ_RATE_ENABLE]) >= sizeof(int)) {

+		pacing = rta_getattr_u32(tb[TCA_FQ_RATE_ENABLE]);

+		if (pacing == 0)

+			fprintf(f, "nopacing ");

+	}

+	if (tb[TCA_FQ_QUANTUM] &&

+	    RTA_PAYLOAD(tb[TCA_FQ_QUANTUM]) >= sizeof(__u32)) {

+		quantum = rta_getattr_u32(tb[TCA_FQ_QUANTUM]);

+		fprintf(f, "quantum %u ", quantum);

+	}

+	if (tb[TCA_FQ_INITIAL_QUANTUM] &&

+	    RTA_PAYLOAD(tb[TCA_FQ_INITIAL_QUANTUM]) >= sizeof(__u32)) {

+		quantum = rta_getattr_u32(tb[TCA_FQ_INITIAL_QUANTUM]);

+		fprintf(f, "initial_quantum %u ", quantum);

+	}

+	if (tb[TCA_FQ_FLOW_MAX_RATE] &&

+	    RTA_PAYLOAD(tb[TCA_FQ_FLOW_MAX_RATE]) >= sizeof(__u32)) {

+		rate = rta_getattr_u32(tb[TCA_FQ_FLOW_MAX_RATE]);

+

+		if (rate != ~0U)

+			fprintf(f, "maxrate %s ", sprint_rate(rate, b1));

+	}

+	if (tb[TCA_FQ_FLOW_DEFAULT_RATE] &&

+	    RTA_PAYLOAD(tb[TCA_FQ_FLOW_DEFAULT_RATE]) >= sizeof(__u32)) {

+		rate = rta_getattr_u32(tb[TCA_FQ_FLOW_DEFAULT_RATE]);

+

+		if (rate != 0)

+			fprintf(f, "defrate %s ", sprint_rate(rate, b1));

+	}

+

+	return 0;

+}

+

+static int fq_print_xstats(struct qdisc_util *qu, FILE *f,

+			   struct rtattr *xstats)

+{

+	struct tc_fq_qd_stats *st;

+

+	if (xstats == NULL)

+		return 0;

+

+	if (RTA_PAYLOAD(xstats) < sizeof(*st))

+		return -1;

+

+	st = RTA_DATA(xstats);

+

+	fprintf(f, "  %u flows (%u inactive, %u throttled)",

+		st->flows, st->inactive_flows, st->throttled_flows);

+

+	if (st->time_next_delayed_flow > 0)

+		fprintf(f, ", next packet delay %llu ns", st->time_next_delayed_flow);

+

+	fprintf(f, "\n  %llu gc, %llu highprio",

+		st->gc_flows, st->highprio_packets);

+

+	if (st->tcp_retrans)

+		fprintf(f, ", %llu retrans", st->tcp_retrans);

+

+	fprintf(f, ", %llu throttled", st->throttled);

+

+	if (st->flows_plimit)

+		fprintf(f, ", %llu flows_plimit", st->flows_plimit);

+

+	if (st->pkts_too_long || st->allocation_errors)

+		fprintf(f, "\n  %llu too long pkts, %llu alloc errors\n",

+			st->pkts_too_long, st->allocation_errors);

+

+	return 0;

+}

+

+struct qdisc_util fq_qdisc_util = {

+	.id		= "fq",

+	.parse_qopt	= fq_parse_opt,

+	.print_qopt	= fq_print_opt,

+	.print_xstats	= fq_print_xstats,

+};

-- 

1.8.3.1