branch Attitude Adjustment

git-svn-id: svn://svn.openwrt.org/openwrt/branches/attitude_adjustment@33625 3c298f89-4303-0410-b956-a3cf2f4a3e73

1 files changed, 839 insertions, 0 deletions

diff --git a/target/linux/generic/patches-3.3/042-fq_codel-Fair-Queue-Codel-AQM.patch b/target/linux/generic/patches-3.3/042-fq_codel-Fair-Queue-Codel-AQM.patch
new file mode 100644
index 000000000..26bbbcb49
--- /dev/null
+++ b/target/linux/generic/patches-3.3/042-fq_codel-Fair-Queue-Codel-AQM.patch
@@ -0,0 +1,839 @@
+From f8cf19c19528a468cc0b9846c0328a94cccdc605 Mon Sep 17 00:00:00 2001
+From: Eric Dumazet <edumazet@google.com>
+Date: Fri, 11 May 2012 09:30:50 +0000
+Subject: [PATCH] fq_codel: Fair Queue Codel AQM
+
+commit 4b549a2ef4bef9965d97cbd992ba67930cd3e0fe upstream.
+
+Fair Queue Codel packet scheduler
+
+Principles :
+
+- Packets are classified (internal classifier or external) on flows.
+- This is a Stochastic model (as we use a hash, several flows might
+                              be hashed on same slot)
+- Each flow has a CoDel managed queue.
+- Flows are linked onto two (Round Robin) lists,
+  so that new flows have priority on old ones.
+
+- For a given flow, packets are not reordered (CoDel uses a FIFO)
+- head drops only.
+- ECN capability is on by default.
+- Very low memory footprint (64 bytes per flow)
+
+tc qdisc ... fq_codel [ limit PACKETS ] [ flows number ]
+                      [ target TIME ] [ interval TIME ] [ noecn ]
+                      [ quantum BYTES ]
+
+defaults : 1024 flows, 10240 packets limit, quantum : device MTU
+           target : 5ms (CoDel default)
+           interval : 100ms (CoDel default)
+
+Impressive results on load :
+
+class htb 1:1 root leaf 10: prio 0 quantum 1514 rate 200000Kbit ceil 200000Kbit burst 1475b/8 mpu 0b overhead 0b cburst 1475b/8 mpu 0b overhead 0b level 0
+ Sent 43304920109 bytes 33063109 pkt (dropped 0, overlimits 0 requeues 0)
+ rate 201691Kbit 28595pps backlog 0b 312p requeues 0
+ lended: 33063109 borrowed: 0 giants: 0
+ tokens: -912 ctokens: -912
+
+class fq_codel 10:1735 parent 10:
+ (dropped 1292, overlimits 0 requeues 0)
+ backlog 15140b 10p requeues 0
+  deficit 1514 count 1 lastcount 1 ldelay 7.1ms
+class fq_codel 10:4524 parent 10:
+ (dropped 1291, overlimits 0 requeues 0)
+ backlog 16654b 11p requeues 0
+  deficit 1514 count 1 lastcount 1 ldelay 7.1ms
+class fq_codel 10:4e74 parent 10:
+ (dropped 1290, overlimits 0 requeues 0)
+ backlog 6056b 4p requeues 0
+  deficit 1514 count 1 lastcount 1 ldelay 6.4ms dropping drop_next 92.0ms
+class fq_codel 10:628a parent 10:
+ (dropped 1289, overlimits 0 requeues 0)
+ backlog 7570b 5p requeues 0
+  deficit 1514 count 1 lastcount 1 ldelay 5.4ms dropping drop_next 90.9ms
+class fq_codel 10:a4b3 parent 10:
+ (dropped 302, overlimits 0 requeues 0)
+ backlog 16654b 11p requeues 0
+  deficit 1514 count 1 lastcount 1 ldelay 7.1ms
+class fq_codel 10:c3c2 parent 10:
+ (dropped 1284, overlimits 0 requeues 0)
+ backlog 13626b 9p requeues 0
+  deficit 1514 count 1 lastcount 1 ldelay 5.9ms
+class fq_codel 10:d331 parent 10:
+ (dropped 299, overlimits 0 requeues 0)
+ backlog 15140b 10p requeues 0
+  deficit 1514 count 1 lastcount 1 ldelay 7.0ms
+class fq_codel 10:d526 parent 10:
+ (dropped 12160, overlimits 0 requeues 0)
+ backlog 35870b 211p requeues 0
+  deficit 1508 count 12160 lastcount 1 ldelay 15.3ms dropping drop_next 247us
+class fq_codel 10:e2c6 parent 10:
+ (dropped 1288, overlimits 0 requeues 0)
+ backlog 15140b 10p requeues 0
+  deficit 1514 count 1 lastcount 1 ldelay 7.1ms
+class fq_codel 10:eab5 parent 10:
+ (dropped 1285, overlimits 0 requeues 0)
+ backlog 16654b 11p requeues 0
+  deficit 1514 count 1 lastcount 1 ldelay 5.9ms
+class fq_codel 10:f220 parent 10:
+ (dropped 1289, overlimits 0 requeues 0)
+ backlog 15140b 10p requeues 0
+  deficit 1514 count 1 lastcount 1 ldelay 7.1ms
+
+qdisc htb 1: root refcnt 6 r2q 10 default 1 direct_packets_stat 0 ver 3.17
+ Sent 43331086547 bytes 33092812 pkt (dropped 0, overlimits 66063544 requeues 71)
+ rate 201697Kbit 28602pps backlog 0b 260p requeues 71
+qdisc fq_codel 10: parent 1:1 limit 10240p flows 65536 target 5.0ms interval 100.0ms ecn
+ Sent 43331086547 bytes 33092812 pkt (dropped 949359, overlimits 0 requeues 0)
+ rate 201697Kbit 28602pps backlog 189352b 260p requeues 0
+  maxpacket 1514 drop_overlimit 0 new_flow_count 5582 ecn_mark 125593
+  new_flows_len 0 old_flows_len 11
+
+PING 172.30.42.18 (172.30.42.18) 56(84) bytes of data.
+64 bytes from 172.30.42.18: icmp_req=1 ttl=64 time=0.227 ms
+64 bytes from 172.30.42.18: icmp_req=2 ttl=64 time=0.165 ms
+64 bytes from 172.30.42.18: icmp_req=3 ttl=64 time=0.166 ms
+64 bytes from 172.30.42.18: icmp_req=4 ttl=64 time=0.151 ms
+64 bytes from 172.30.42.18: icmp_req=5 ttl=64 time=0.164 ms
+64 bytes from 172.30.42.18: icmp_req=6 ttl=64 time=0.172 ms
+64 bytes from 172.30.42.18: icmp_req=7 ttl=64 time=0.175 ms
+64 bytes from 172.30.42.18: icmp_req=8 ttl=64 time=0.183 ms
+64 bytes from 172.30.42.18: icmp_req=9 ttl=64 time=0.158 ms
+64 bytes from 172.30.42.18: icmp_req=10 ttl=64 time=0.200 ms
+
+10 packets transmitted, 10 received, 0% packet loss, time 8999ms
+rtt min/avg/max/mdev = 0.151/0.176/0.227/0.022 ms
+
+Much better than SFQ because of priority given to new flows, and fast
+path dirtying less cache lines.
+
+Signed-off-by: Eric Dumazet <edumazet@google.com>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ include/linux/pkt_sched.h |   54 ++++
+ net/sched/Kconfig         |   11 +
+ net/sched/Makefile        |    1 +
+ net/sched/sch_fq_codel.c  |  624 +++++++++++++++++++++++++++++++++++++++++++++
+ 4 files changed, 690 insertions(+)
+ create mode 100644 net/sched/sch_fq_codel.c
+
+--- a/include/linux/pkt_sched.h
++++ b/include/linux/pkt_sched.h
+@@ -659,4 +659,58 @@ struct tc_codel_xstats {
+ 	__u32	dropping;  /* are we in dropping state ? */
+ };
+ 
++/* FQ_CODEL */
++
++enum {
++	TCA_FQ_CODEL_UNSPEC,
++	TCA_FQ_CODEL_TARGET,
++	TCA_FQ_CODEL_LIMIT,
++	TCA_FQ_CODEL_INTERVAL,
++	TCA_FQ_CODEL_ECN,
++	TCA_FQ_CODEL_FLOWS,
++	TCA_FQ_CODEL_QUANTUM,
++	__TCA_FQ_CODEL_MAX
++};
++
++#define TCA_FQ_CODEL_MAX	(__TCA_FQ_CODEL_MAX - 1)
++
++enum {
++	TCA_FQ_CODEL_XSTATS_QDISC,
++	TCA_FQ_CODEL_XSTATS_CLASS,
++};
++
++struct tc_fq_codel_qd_stats {
++	__u32	maxpacket;	/* largest packet we've seen so far */
++	__u32	drop_overlimit; /* number of time max qdisc
++				 * packet limit was hit
++				 */
++	__u32	ecn_mark;	/* number of packets we ECN marked
++				 * instead of being dropped
++				 */
++	__u32	new_flow_count; /* number of time packets
++				 * created a 'new flow'
++				 */
++	__u32	new_flows_len;	/* count of flows in new list */
++	__u32	old_flows_len;	/* count of flows in old list */
++};
++
++struct tc_fq_codel_cl_stats {
++	__s32	deficit;
++	__u32	ldelay;		/* in-queue delay seen by most recently
++				 * dequeued packet
++				 */
++	__u32	count;
++	__u32	lastcount;
++	__u32	dropping;
++	__s32	drop_next;
++};
++
++struct tc_fq_codel_xstats {
++	__u32	type;
++	union {
++		struct tc_fq_codel_qd_stats qdisc_stats;
++		struct tc_fq_codel_cl_stats class_stats;
++	};
++};
++
+ #endif
+--- a/net/sched/Kconfig
++++ b/net/sched/Kconfig
+@@ -261,6 +261,17 @@ config NET_SCH_CODEL
+ 
+ 	  If unsure, say N.
+ 
++config NET_SCH_FQ_CODEL
++	tristate "Fair Queue Controlled Delay AQM (FQ_CODEL)"
++	help
++	  Say Y here if you want to use the FQ Controlled Delay (FQ_CODEL)
++	  packet scheduling algorithm.
++
++	  To compile this driver as a module, choose M here: the module
++	  will be called sch_fq_codel.
++
++	  If unsure, say N.
++
+ config NET_SCH_INGRESS
+ 	tristate "Ingress Qdisc"
+ 	depends on NET_CLS_ACT
+--- a/net/sched/Makefile
++++ b/net/sched/Makefile
+@@ -37,6 +37,7 @@ obj-$(CONFIG_NET_SCH_MQPRIO)	+= sch_mqpr
+ obj-$(CONFIG_NET_SCH_CHOKE)	+= sch_choke.o
+ obj-$(CONFIG_NET_SCH_QFQ)	+= sch_qfq.o
+ obj-$(CONFIG_NET_SCH_CODEL)	+= sch_codel.o
++obj-$(CONFIG_NET_SCH_FQ_CODEL)	+= sch_fq_codel.o
+ 
+ obj-$(CONFIG_NET_CLS_U32)	+= cls_u32.o
+ obj-$(CONFIG_NET_CLS_ROUTE4)	+= cls_route.o
+--- /dev/null
++++ b/net/sched/sch_fq_codel.c
+@@ -0,0 +1,624 @@
++/*
++ * Fair Queue CoDel discipline
++ *
++ *	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.
++ *
++ *  Copyright (C) 2012 Eric Dumazet <edumazet@google.com>
++ */
++
++#include <linux/module.h>
++#include <linux/types.h>
++#include <linux/kernel.h>
++#include <linux/jiffies.h>
++#include <linux/string.h>
++#include <linux/in.h>
++#include <linux/errno.h>
++#include <linux/init.h>
++#include <linux/skbuff.h>
++#include <linux/jhash.h>
++#include <linux/slab.h>
++#include <linux/vmalloc.h>
++#include <net/netlink.h>
++#include <net/pkt_sched.h>
++#include <net/flow_keys.h>
++#include <net/codel.h>
++
++/*	Fair Queue CoDel.
++ *
++ * Principles :
++ * Packets are classified (internal classifier or external) on flows.
++ * This is a Stochastic model (as we use a hash, several flows
++ *			       might be hashed on same slot)
++ * Each flow has a CoDel managed queue.
++ * Flows are linked onto two (Round Robin) lists,
++ * so that new flows have priority on old ones.
++ *
++ * For a given flow, packets are not reordered (CoDel uses a FIFO)
++ * head drops only.
++ * ECN capability is on by default.
++ * Low memory footprint (64 bytes per flow)
++ */
++
++struct fq_codel_flow {
++	struct sk_buff	  *head;
++	struct sk_buff	  *tail;
++	struct list_head  flowchain;
++	int		  deficit;
++	u32		  dropped; /* number of drops (or ECN marks) on this flow */
++	struct codel_vars cvars;
++}; /* please try to keep this structure <= 64 bytes */
++
++struct fq_codel_sched_data {
++	struct tcf_proto *filter_list;	/* optional external classifier */
++	struct fq_codel_flow *flows;	/* Flows table [flows_cnt] */
++	u32		*backlogs;	/* backlog table [flows_cnt] */
++	u32		flows_cnt;	/* number of flows */
++	u32		perturbation;	/* hash perturbation */
++	u32		quantum;	/* psched_mtu(qdisc_dev(sch)); */
++	struct codel_params cparams;
++	struct codel_stats cstats;
++	u32		drop_overlimit;
++	u32		new_flow_count;
++
++	struct list_head new_flows;	/* list of new flows */
++	struct list_head old_flows;	/* list of old flows */
++};
++
++static unsigned int fq_codel_hash(const struct fq_codel_sched_data *q,
++				  const struct sk_buff *skb)
++{
++	struct flow_keys keys;
++	unsigned int hash;
++
++	skb_flow_dissect(skb, &keys);
++	hash = jhash_3words((__force u32)keys.dst,
++			    (__force u32)keys.src ^ keys.ip_proto,
++			    (__force u32)keys.ports, q->perturbation);
++	return ((u64)hash * q->flows_cnt) >> 32;
++}
++
++static unsigned int fq_codel_classify(struct sk_buff *skb, struct Qdisc *sch,
++				      int *qerr)
++{
++	struct fq_codel_sched_data *q = qdisc_priv(sch);
++	struct tcf_result res;
++	int result;
++
++	if (TC_H_MAJ(skb->priority) == sch->handle &&
++	    TC_H_MIN(skb->priority) > 0 &&
++	    TC_H_MIN(skb->priority) <= q->flows_cnt)
++		return TC_H_MIN(skb->priority);
++
++	if (!q->filter_list)
++		return fq_codel_hash(q, skb) + 1;
++
++	*qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
++	result = tc_classify(skb, q->filter_list, &res);
++	if (result >= 0) {
++#ifdef CONFIG_NET_CLS_ACT
++		switch (result) {
++		case TC_ACT_STOLEN:
++		case TC_ACT_QUEUED:
++			*qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
++		case TC_ACT_SHOT:
++			return 0;
++		}
++#endif
++		if (TC_H_MIN(res.classid) <= q->flows_cnt)
++			return TC_H_MIN(res.classid);
++	}
++	return 0;
++}
++
++/* helper functions : might be changed when/if skb use a standard list_head */
++
++/* remove one skb from head of slot queue */
++static inline struct sk_buff *dequeue_head(struct fq_codel_flow *flow)
++{
++	struct sk_buff *skb = flow->head;
++
++	flow->head = skb->next;
++	skb->next = NULL;
++	return skb;
++}
++
++/* add skb to flow queue (tail add) */
++static inline void flow_queue_add(struct fq_codel_flow *flow,
++				  struct sk_buff *skb)
++{
++	if (flow->head == NULL)
++		flow->head = skb;
++	else
++		flow->tail->next = skb;
++	flow->tail = skb;
++	skb->next = NULL;
++}
++
++static unsigned int fq_codel_drop(struct Qdisc *sch)
++{
++	struct fq_codel_sched_data *q = qdisc_priv(sch);
++	struct sk_buff *skb;
++	unsigned int maxbacklog = 0, idx = 0, i, len;
++	struct fq_codel_flow *flow;
++
++	/* Queue is full! Find the fat flow and drop packet from it.
++	 * This might sound expensive, but with 1024 flows, we scan
++	 * 4KB of memory, and we dont need to handle a complex tree
++	 * in fast path (packet queue/enqueue) with many cache misses.
++	 */
++	for (i = 0; i < q->flows_cnt; i++) {
++		if (q->backlogs[i] > maxbacklog) {
++			maxbacklog = q->backlogs[i];
++			idx = i;
++		}
++	}
++	flow = &q->flows[idx];
++	skb = dequeue_head(flow);
++	len = qdisc_pkt_len(skb);
++	q->backlogs[idx] -= len;
++	kfree_skb(skb);
++	sch->q.qlen--;
++	sch->qstats.drops++;
++	sch->qstats.backlog -= len;
++	flow->dropped++;
++	return idx;
++}
++
++static int fq_codel_enqueue(struct sk_buff *skb, struct Qdisc *sch)
++{
++	struct fq_codel_sched_data *q = qdisc_priv(sch);
++	unsigned int idx;
++	struct fq_codel_flow *flow;
++	int uninitialized_var(ret);
++
++	idx = fq_codel_classify(skb, sch, &ret);
++	if (idx == 0) {
++		if (ret & __NET_XMIT_BYPASS)
++			sch->qstats.drops++;
++		kfree_skb(skb);
++		return ret;
++	}
++	idx--;
++
++	codel_set_enqueue_time(skb);
++	flow = &q->flows[idx];
++	flow_queue_add(flow, skb);
++	q->backlogs[idx] += qdisc_pkt_len(skb);
++	sch->qstats.backlog += qdisc_pkt_len(skb);
++
++	if (list_empty(&flow->flowchain)) {
++		list_add_tail(&flow->flowchain, &q->new_flows);
++		codel_vars_init(&flow->cvars);
++		q->new_flow_count++;
++		flow->deficit = q->quantum;
++		flow->dropped = 0;
++	}
++	if (++sch->q.qlen < sch->limit)
++		return NET_XMIT_SUCCESS;
++
++	q->drop_overlimit++;
++	/* Return Congestion Notification only if we dropped a packet
++	 * from this flow.
++	 */
++	if (fq_codel_drop(sch) == idx)
++		return NET_XMIT_CN;
++
++	/* As we dropped a packet, better let upper stack know this */
++	qdisc_tree_decrease_qlen(sch, 1);
++	return NET_XMIT_SUCCESS;
++}
++
++/* This is the specific function called from codel_dequeue()
++ * to dequeue a packet from queue. Note: backlog is handled in
++ * codel, we dont need to reduce it here.
++ */
++static struct sk_buff *dequeue(struct codel_vars *vars, struct Qdisc *sch)
++{
++	struct fq_codel_flow *flow;
++	struct sk_buff *skb = NULL;
++
++	flow = container_of(vars, struct fq_codel_flow, cvars);
++	if (flow->head) {
++		skb = dequeue_head(flow);
++		sch->qstats.backlog -= qdisc_pkt_len(skb);
++		sch->q.qlen--;
++	}
++	return skb;
++}
++
++static struct sk_buff *fq_codel_dequeue(struct Qdisc *sch)
++{
++	struct fq_codel_sched_data *q = qdisc_priv(sch);
++	struct sk_buff *skb;
++	struct fq_codel_flow *flow;
++	struct list_head *head;
++	u32 prev_drop_count, prev_ecn_mark;
++
++begin:
++	head = &q->new_flows;
++	if (list_empty(head)) {
++		head = &q->old_flows;
++		if (list_empty(head))
++			return NULL;
++	}
++	flow = list_first_entry(head, struct fq_codel_flow, flowchain);
++
++	if (flow->deficit <= 0) {
++		flow->deficit += q->quantum;
++		list_move_tail(&flow->flowchain, &q->old_flows);
++		goto begin;
++	}
++
++	prev_drop_count = q->cstats.drop_count;
++	prev_ecn_mark = q->cstats.ecn_mark;
++
++	skb = codel_dequeue(sch, &q->cparams, &flow->cvars, &q->cstats,
++			    dequeue, &q->backlogs[flow - q->flows]);
++
++	flow->dropped += q->cstats.drop_count - prev_drop_count;
++	flow->dropped += q->cstats.ecn_mark - prev_ecn_mark;
++
++	if (!skb) {
++		/* force a pass through old_flows to prevent starvation */
++		if ((head == &q->new_flows) && !list_empty(&q->old_flows))
++			list_move_tail(&flow->flowchain, &q->old_flows);
++		else
++			list_del_init(&flow->flowchain);
++		goto begin;
++	}
++	qdisc_bstats_update(sch, skb);
++	flow->deficit -= qdisc_pkt_len(skb);
++	/* We cant call qdisc_tree_decrease_qlen() if our qlen is 0,
++	 * or HTB crashes. Defer it for next round.
++	 */
++	if (q->cstats.drop_count && sch->q.qlen) {
++		qdisc_tree_decrease_qlen(sch, q->cstats.drop_count);
++		q->cstats.drop_count = 0;
++	}
++	return skb;
++}
++
++static void fq_codel_reset(struct Qdisc *sch)
++{
++	struct sk_buff *skb;
++
++	while ((skb = fq_codel_dequeue(sch)) != NULL)
++		kfree_skb(skb);
++}
++
++static const struct nla_policy fq_codel_policy[TCA_FQ_CODEL_MAX + 1] = {
++	[TCA_FQ_CODEL_TARGET]	= { .type = NLA_U32 },
++	[TCA_FQ_CODEL_LIMIT]	= { .type = NLA_U32 },
++	[TCA_FQ_CODEL_INTERVAL]	= { .type = NLA_U32 },
++	[TCA_FQ_CODEL_ECN]	= { .type = NLA_U32 },
++	[TCA_FQ_CODEL_FLOWS]	= { .type = NLA_U32 },
++	[TCA_FQ_CODEL_QUANTUM]	= { .type = NLA_U32 },
++};
++
++static int fq_codel_change(struct Qdisc *sch, struct nlattr *opt)
++{
++	struct fq_codel_sched_data *q = qdisc_priv(sch);
++	struct nlattr *tb[TCA_FQ_CODEL_MAX + 1];
++	int err;
++
++	if (!opt)
++		return -EINVAL;
++
++	err = nla_parse_nested(tb, TCA_FQ_CODEL_MAX, opt, fq_codel_policy);
++	if (err < 0)
++		return err;
++	if (tb[TCA_FQ_CODEL_FLOWS]) {
++		if (q->flows)
++			return -EINVAL;
++		q->flows_cnt = nla_get_u32(tb[TCA_FQ_CODEL_FLOWS]);
++		if (!q->flows_cnt ||
++		    q->flows_cnt > 65536)
++			return -EINVAL;
++	}
++	sch_tree_lock(sch);
++
++	if (tb[TCA_FQ_CODEL_TARGET]) {
++		u64 target = nla_get_u32(tb[TCA_FQ_CODEL_TARGET]);
++
++		q->cparams.target = (target * NSEC_PER_USEC) >> CODEL_SHIFT;
++	}
++
++	if (tb[TCA_FQ_CODEL_INTERVAL]) {
++		u64 interval = nla_get_u32(tb[TCA_FQ_CODEL_INTERVAL]);
++
++		q->cparams.interval = (interval * NSEC_PER_USEC) >> CODEL_SHIFT;
++	}
++
++	if (tb[TCA_FQ_CODEL_LIMIT])
++		sch->limit = nla_get_u32(tb[TCA_FQ_CODEL_LIMIT]);
++
++	if (tb[TCA_FQ_CODEL_ECN])
++		q->cparams.ecn = !!nla_get_u32(tb[TCA_FQ_CODEL_ECN]);
++
++	if (tb[TCA_FQ_CODEL_QUANTUM])
++		q->quantum = max(256U, nla_get_u32(tb[TCA_FQ_CODEL_QUANTUM]));
++
++	while (sch->q.qlen > sch->limit) {
++		struct sk_buff *skb = fq_codel_dequeue(sch);
++
++		kfree_skb(skb);
++		q->cstats.drop_count++;
++	}
++	qdisc_tree_decrease_qlen(sch, q->cstats.drop_count);
++	q->cstats.drop_count = 0;
++
++	sch_tree_unlock(sch);
++	return 0;
++}
++
++static void *fq_codel_zalloc(size_t sz)
++{
++	void *ptr = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN);
++
++	if (!ptr)
++		ptr = vzalloc(sz);
++	return ptr;
++}
++
++static void fq_codel_free(void *addr)
++{
++	if (addr) {
++		if (is_vmalloc_addr(addr))
++			vfree(addr);
++		else
++			kfree(addr);
++	}
++}
++
++static void fq_codel_destroy(struct Qdisc *sch)
++{
++	struct fq_codel_sched_data *q = qdisc_priv(sch);
++
++	tcf_destroy_chain(&q->filter_list);
++	fq_codel_free(q->backlogs);
++	fq_codel_free(q->flows);
++}
++
++static int fq_codel_init(struct Qdisc *sch, struct nlattr *opt)
++{
++	struct fq_codel_sched_data *q = qdisc_priv(sch);
++	int i;
++
++	sch->limit = 10*1024;
++	q->flows_cnt = 1024;
++	q->quantum = psched_mtu(qdisc_dev(sch));
++	q->perturbation = net_random();
++	INIT_LIST_HEAD(&q->new_flows);
++	INIT_LIST_HEAD(&q->old_flows);
++	codel_params_init(&q->cparams);
++	codel_stats_init(&q->cstats);
++	q->cparams.ecn = true;
++
++	if (opt) {
++		int err = fq_codel_change(sch, opt);
++		if (err)
++			return err;
++	}
++
++	if (!q->flows) {
++		q->flows = fq_codel_zalloc(q->flows_cnt *
++					   sizeof(struct fq_codel_flow));
++		if (!q->flows)
++			return -ENOMEM;
++		q->backlogs = fq_codel_zalloc(q->flows_cnt * sizeof(u32));
++		if (!q->backlogs) {
++			fq_codel_free(q->flows);
++			return -ENOMEM;
++		}
++		for (i = 0; i < q->flows_cnt; i++) {
++			struct fq_codel_flow *flow = q->flows + i;
++
++			INIT_LIST_HEAD(&flow->flowchain);
++		}
++	}
++	if (sch->limit >= 1)
++		sch->flags |= TCQ_F_CAN_BYPASS;
++	else
++		sch->flags &= ~TCQ_F_CAN_BYPASS;
++	return 0;
++}
++
++static int fq_codel_dump(struct Qdisc *sch, struct sk_buff *skb)
++{
++	struct fq_codel_sched_data *q = qdisc_priv(sch);
++	struct nlattr *opts;
++
++	opts = nla_nest_start(skb, TCA_OPTIONS);
++	if (opts == NULL)
++		goto nla_put_failure;
++
++	if (nla_put_u32(skb, TCA_FQ_CODEL_TARGET,
++			codel_time_to_us(q->cparams.target)) ||
++	    nla_put_u32(skb, TCA_FQ_CODEL_LIMIT,
++			sch->limit) ||
++	    nla_put_u32(skb, TCA_FQ_CODEL_INTERVAL,
++			codel_time_to_us(q->cparams.interval)) ||
++	    nla_put_u32(skb, TCA_FQ_CODEL_ECN,
++			q->cparams.ecn) ||
++	    nla_put_u32(skb, TCA_FQ_CODEL_QUANTUM,
++			q->quantum) ||
++	    nla_put_u32(skb, TCA_FQ_CODEL_FLOWS,
++			q->flows_cnt))
++		goto nla_put_failure;
++
++	nla_nest_end(skb, opts);
++	return skb->len;
++
++nla_put_failure:
++	return -1;
++}
++
++static int fq_codel_dump_stats(struct Qdisc *sch, struct gnet_dump *d)
++{
++	struct fq_codel_sched_data *q = qdisc_priv(sch);
++	struct tc_fq_codel_xstats st = {
++		.type				= TCA_FQ_CODEL_XSTATS_QDISC,
++		.qdisc_stats.maxpacket		= q->cstats.maxpacket,
++		.qdisc_stats.drop_overlimit	= q->drop_overlimit,
++		.qdisc_stats.ecn_mark		= q->cstats.ecn_mark,
++		.qdisc_stats.new_flow_count	= q->new_flow_count,
++	};
++	struct list_head *pos;
++
++	list_for_each(pos, &q->new_flows)
++		st.qdisc_stats.new_flows_len++;
++
++	list_for_each(pos, &q->old_flows)
++		st.qdisc_stats.old_flows_len++;
++
++	return gnet_stats_copy_app(d, &st, sizeof(st));
++}
++
++static struct Qdisc *fq_codel_leaf(struct Qdisc *sch, unsigned long arg)
++{
++	return NULL;
++}
++
++static unsigned long fq_codel_get(struct Qdisc *sch, u32 classid)
++{
++	return 0;
++}
++
++static unsigned long fq_codel_bind(struct Qdisc *sch, unsigned long parent,
++			      u32 classid)
++{
++	/* we cannot bypass queue discipline anymore */
++	sch->flags &= ~TCQ_F_CAN_BYPASS;
++	return 0;
++}
++
++static void fq_codel_put(struct Qdisc *q, unsigned long cl)
++{
++}
++
++static struct tcf_proto **fq_codel_find_tcf(struct Qdisc *sch, unsigned long cl)
++{
++	struct fq_codel_sched_data *q = qdisc_priv(sch);
++
++	if (cl)
++		return NULL;
++	return &q->filter_list;
++}
++
++static int fq_codel_dump_class(struct Qdisc *sch, unsigned long cl,
++			  struct sk_buff *skb, struct tcmsg *tcm)
++{
++	tcm->tcm_handle |= TC_H_MIN(cl);
++	return 0;
++}
++
++static int fq_codel_dump_class_stats(struct Qdisc *sch, unsigned long cl,
++				     struct gnet_dump *d)
++{
++	struct fq_codel_sched_data *q = qdisc_priv(sch);
++	u32 idx = cl - 1;
++	struct gnet_stats_queue qs = { 0 };
++	struct tc_fq_codel_xstats xstats;
++
++	if (idx < q->flows_cnt) {
++		const struct fq_codel_flow *flow = &q->flows[idx];
++		const struct sk_buff *skb = flow->head;
++
++		memset(&xstats, 0, sizeof(xstats));
++		xstats.type = TCA_FQ_CODEL_XSTATS_CLASS;
++		xstats.class_stats.deficit = flow->deficit;
++		xstats.class_stats.ldelay =
++			codel_time_to_us(flow->cvars.ldelay);
++		xstats.class_stats.count = flow->cvars.count;
++		xstats.class_stats.lastcount = flow->cvars.lastcount;
++		xstats.class_stats.dropping = flow->cvars.dropping;
++		if (flow->cvars.dropping) {
++			codel_tdiff_t delta = flow->cvars.drop_next -
++					      codel_get_time();
++
++			xstats.class_stats.drop_next = (delta >= 0) ?
++				codel_time_to_us(delta) :
++				-codel_time_to_us(-delta);
++		}
++		while (skb) {
++			qs.qlen++;
++			skb = skb->next;
++		}
++		qs.backlog = q->backlogs[idx];
++		qs.drops = flow->dropped;
++	}
++	if (gnet_stats_copy_queue(d, &qs) < 0)
++		return -1;
++	if (idx < q->flows_cnt)
++		return gnet_stats_copy_app(d, &xstats, sizeof(xstats));
++	return 0;
++}
++
++static void fq_codel_walk(struct Qdisc *sch, struct qdisc_walker *arg)
++{
++	struct fq_codel_sched_data *q = qdisc_priv(sch);
++	unsigned int i;
++
++	if (arg->stop)
++		return;
++
++	for (i = 0; i < q->flows_cnt; i++) {
++		if (list_empty(&q->flows[i].flowchain) ||
++		    arg->count < arg->skip) {
++			arg->count++;
++			continue;
++		}
++		if (arg->fn(sch, i + 1, arg) < 0) {
++			arg->stop = 1;
++			break;
++		}
++		arg->count++;
++	}
++}
++
++static const struct Qdisc_class_ops fq_codel_class_ops = {
++	.leaf		=	fq_codel_leaf,
++	.get		=	fq_codel_get,
++	.put		=	fq_codel_put,
++	.tcf_chain	=	fq_codel_find_tcf,
++	.bind_tcf	=	fq_codel_bind,
++	.unbind_tcf	=	fq_codel_put,
++	.dump		=	fq_codel_dump_class,
++	.dump_stats	=	fq_codel_dump_class_stats,
++	.walk		=	fq_codel_walk,
++};
++
++static struct Qdisc_ops fq_codel_qdisc_ops __read_mostly = {
++	.cl_ops		=	&fq_codel_class_ops,
++	.id		=	"fq_codel",
++	.priv_size	=	sizeof(struct fq_codel_sched_data),
++	.enqueue	=	fq_codel_enqueue,
++	.dequeue	=	fq_codel_dequeue,
++	.peek		=	qdisc_peek_dequeued,
++	.drop		=	fq_codel_drop,
++	.init		=	fq_codel_init,
++	.reset		=	fq_codel_reset,
++	.destroy	=	fq_codel_destroy,
++	.change		=	fq_codel_change,
++	.dump		=	fq_codel_dump,
++	.dump_stats =	fq_codel_dump_stats,
++	.owner		=	THIS_MODULE,
++};
++
++static int __init fq_codel_module_init(void)
++{
++	return register_qdisc(&fq_codel_qdisc_ops);
++}
++
++static void __exit fq_codel_module_exit(void)
++{
++	unregister_qdisc(&fq_codel_qdisc_ops);
++}
++
++module_init(fq_codel_module_init)
++module_exit(fq_codel_module_exit)
++MODULE_AUTHOR("Eric Dumazet");
++MODULE_LICENSE("GPL");