diff mbox

[net-next] net_sched: red: split red_parms into parms and vars

Message ID 1325766316.2415.18.camel@edumazet-HP-Compaq-6005-Pro-SFF-PC
State Accepted, archived
Delegated to: David Miller
Headers show

Commit Message

Eric Dumazet Jan. 5, 2012, 12:25 p.m. UTC 
This patch splits the red_parms structure into two components.

One holding the RED 'constant' parameters, and one containing the
variables.

This permits a size reduction of GRED qdisc, and is a preliminary step
to add an optional RED unit to SFQ. 

SFQRED will have a single red_parms structure shared by all flows, and a
private red_vars per flow.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Dave Taht <dave.taht@gmail.com>
CC: Stephen Hemminger <shemminger@vyatta.com>
---
 include/net/red.h     |   98 ++++++++++++++++++++++------------------
 net/sched/sch_choke.c |   40 ++++++++--------
 net/sched/sch_gred.c  |   45 +++++++++---------
 net/sched/sch_red.c   |   29 ++++++-----
 4 files changed, 117 insertions(+), 95 deletions(-)



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Comments

Dave Taht Jan. 5, 2012, 1:03 p.m. UTC | #1 
On Thu, Jan 5, 2012 at 1:25 PM, Eric Dumazet <eric.dumazet@gmail.com> wrote:
> This patch splits the red_parms structure into two components.
>
> One holding the RED 'constant' parameters, and one containing the
> variables.
>
> This permits a size reduction of GRED qdisc, and is a preliminary step
> to add an optional RED unit to SFQ.

ah. I see where you are going with this. You are trying also to get your
'time in red' adaptation idea done, aren't you, or at least lay the groundwork
for that?

Are you trying to make the 3.3 merge window for all this?

I don't want to discourage you in any way, but byte oriented RED
with or without TSO doesn't work in your typical asymmetric
environment. If you set an appropriate byte limit for
stuff going one way, you end up with acks going out of
control - and vice versa.

and/or packet oriented RED has some hope, but in either
case you have to do something intelligent with a giant TSO
stream if you are going to use it on a server or host.

And the basic red still has two flaws that may or may
not go away with your adaptation, or combination with
SFQ - (I do retain hope, though)

I think you already grok this and you've already got the solution
outlined :)

so I'm going to go away now and finish writing up
what the problems are in sch_md, which are legion...

Keep having fun. I'll plan on a new build by the weekend.
Eric Dumazet Jan. 5, 2012, 1:39 p.m. UTC | #2 
Le jeudi 05 janvier 2012 à 14:03 +0100, Dave Taht a écrit :
> On Thu, Jan 5, 2012 at 1:25 PM, Eric Dumazet <eric.dumazet@gmail.com> wrote:
> > This patch splits the red_parms structure into two components.
> >
> > One holding the RED 'constant' parameters, and one containing the
> > variables.
> >
> > This permits a size reduction of GRED qdisc, and is a preliminary step
> > to add an optional RED unit to SFQ.
> 
> ah. I see where you are going with this. You are trying also to get your
> 'time in red' adaptation idea done, aren't you, or at least lay the groundwork
> for that?
> 

RED algo is agnostic : The quantity you want to average can be :

1) queue length in bytes
2) queue length in packets
3) time of residence in queue
...

Adding 3) is very easy.

> Are you trying to make the 3.3 merge window for all this?
> 

Its up to David ;)

> I don't want to discourage you in any way, but byte oriented RED
> with or without TSO doesn't work in your typical asymmetric
> environment. If you set an appropriate byte limit for
> stuff going one way, you end up with acks going out of
> control - and vice versa.

TSO has little impact if you use "average queue length in bytes"

My main concern about adding RED is to be able to perform ecn marking
instead of mere packet drops.

In the case of your router, TSO is a non issue, since a router should
handle MTU sized skbs. (disable GRO at ingress side)

> 
> and/or packet oriented RED has some hope, but in either
> case you have to do something intelligent with a giant TSO
> stream if you are going to use it on a server or host.
> 

Again, a flow is a flow, and TSO is just a big packet.

Once you separate flows (using SFQ or QFQ), adding a RED unit permits
early drops only on flows that want to be unfair.

> And the basic red still has two flaws that may or may
> not go away with your adaptation, or combination with
> SFQ - (I do retain hope, though)

I only want to 'activate' red on selected backlogged flows.

tc qdisc add dev eth0 root sfq[red] \
	limit 3000 headdrop flows 512 divisor 16384 \
	redflowlimit 200000b ecn

Problems of RED are :

1) the 'average' on highly variable trafic : It means nothing
interesting at all.

2) the idle time management requires to specify the link bandwidth, as a
fixed value. This is a problem.

In case of SFQRED, flow bandwidth is unknown, or very dynamic.

This is why I plan to reset qavg to 0 each time a flow becomes 'active',
and not care of idle time at all.



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David Miller Jan. 5, 2012, 7:08 p.m. UTC | #3 
From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Thu, 05 Jan 2012 13:25:16 +0100

> This patch splits the red_parms structure into two components.
> 
> One holding the RED 'constant' parameters, and one containing the
> variables.
> 
> This permits a size reduction of GRED qdisc, and is a preliminary step
> to add an optional RED unit to SFQ. 
> 
> SFQRED will have a single red_parms structure shared by all flows, and a
> private red_vars per flow.
> 
> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>

Applied.
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Eric Dumazet Jan. 6, 2012, 5:47 a.m. UTC | #4 
Le jeudi 05 janvier 2012 à 14:39 +0100, Eric Dumazet a écrit :

> Problems of RED are :
> 
> 1) the 'average' on highly variable trafic : It means nothing
> interesting at all.
> 
> 2) the idle time management requires to specify the link bandwidth, as a
> fixed value. This is a problem.

A third problem is that ECN marking is performed on the packet we add to
the tail of the queue. It's very late...

I am currently testing my SFQRED and I try to add ECN in the first
packet in queue so that TCP can react faster.



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Dave Taht Jan. 6, 2012, 8:31 a.m. UTC | #5 
On Fri, Jan 6, 2012 at 6:47 AM, Eric Dumazet <eric.dumazet@gmail.com> wrote:
> Le jeudi 05 janvier 2012 à 14:39 +0100, Eric Dumazet a écrit :
>
>> Problems of RED are :
>>
>> 1) the 'average' on highly variable trafic : It means nothing
>> interesting at all.
>>
>> 2) the idle time management requires to specify the link bandwidth, as a
>> fixed value. This is a problem.
>
> A third problem is that ECN marking is performed on the packet we add to
> the tail of the queue. It's very late...
>
> I am currently testing my SFQRED and I try to add ECN in the first
> packet in queue so that TCP can react faster.

If you are in particular looking for stuff worth marking, vs dropping...
you could even look deeper in the queue (group) than the first packet.

I am reminded somewhat of how david mills handled the first
NSFnet congestion collapse on the fuzzball.

http://osdir.com/ml/culture.internet.history/2004-12/msg00003.html

"When a new packet arrived and no buffer space was available, the
output queues were scanned looking for the biggest elephant (total
byte count on all queues from the same IP address) and killed its
biggest packet. Gunshots continued until either the arriving packet
got shot or there was enough room to save it. It all worked
gangbusters and the poor ftpers never found out. "

>
>
>
diff mbox

Patch

diff --git a/include/net/red.h b/include/net/red.h
index ef715a1..baab385 100644
--- a/include/net/red.h
+++ b/include/net/red.h
@@ -137,7 +137,9 @@  struct red_parms {
 	u8		Wlog;		/* log(W)		*/
 	u8		Plog;		/* random number bits	*/
 	u8		Stab[RED_STAB_SIZE];
+};
 
+struct red_vars {
 	/* Variables */
 	int		qcount;		/* Number of packets since last random
 					   number generation */
@@ -152,6 +154,16 @@  static inline u32 red_maxp(u8 Plog)
 	return Plog < 32 ? (~0U >> Plog) : ~0U;
 }
 
+static inline void red_set_vars(struct red_vars *v)
+{
+	/* Reset average queue length, the value is strictly bound
+	 * to the parameters below, reseting hurts a bit but leaving
+	 * it might result in an unreasonable qavg for a while. --TGR
+	 */
+	v->qavg		= 0;
+
+	v->qcount	= -1;
+}
 
 static inline void red_set_parms(struct red_parms *p,
 				 u32 qth_min, u32 qth_max, u8 Wlog, u8 Plog,
@@ -160,13 +172,6 @@  static inline void red_set_parms(struct red_parms *p,
 	int delta = qth_max - qth_min;
 	u32 max_p_delta;
 
-	/* Reset average queue length, the value is strictly bound
-	 * to the parameters below, reseting hurts a bit but leaving
-	 * it might result in an unreasonable qavg for a while. --TGR
-	 */
-	p->qavg		= 0;
-
-	p->qcount	= -1;
 	p->qth_min	= qth_min << Wlog;
 	p->qth_max	= qth_max << Wlog;
 	p->Wlog		= Wlog;
@@ -197,31 +202,32 @@  static inline void red_set_parms(struct red_parms *p,
 	memcpy(p->Stab, stab, sizeof(p->Stab));
 }
 
-static inline int red_is_idling(const struct red_parms *p)
+static inline int red_is_idling(const struct red_vars *v)
 {
-	return p->qidlestart.tv64 != 0;
+	return v->qidlestart.tv64 != 0;
 }
 
-static inline void red_start_of_idle_period(struct red_parms *p)
+static inline void red_start_of_idle_period(struct red_vars *v)
 {
-	p->qidlestart = ktime_get();
+	v->qidlestart = ktime_get();
 }
 
-static inline void red_end_of_idle_period(struct red_parms *p)
+static inline void red_end_of_idle_period(struct red_vars *v)
 {
-	p->qidlestart.tv64 = 0;
+	v->qidlestart.tv64 = 0;
 }
 
-static inline void red_restart(struct red_parms *p)
+static inline void red_restart(struct red_vars *v)
 {
-	red_end_of_idle_period(p);
-	p->qavg = 0;
-	p->qcount = -1;
+	red_end_of_idle_period(v);
+	v->qavg = 0;
+	v->qcount = -1;
 }
 
-static inline unsigned long red_calc_qavg_from_idle_time(const struct red_parms *p)
+static inline unsigned long red_calc_qavg_from_idle_time(const struct red_parms *p,
+							 const struct red_vars *v)
 {
-	s64 delta = ktime_us_delta(ktime_get(), p->qidlestart);
+	s64 delta = ktime_us_delta(ktime_get(), v->qidlestart);
 	long us_idle = min_t(s64, delta, p->Scell_max);
 	int  shift;
 
@@ -248,7 +254,7 @@  static inline unsigned long red_calc_qavg_from_idle_time(const struct red_parms
 	shift = p->Stab[(us_idle >> p->Scell_log) & RED_STAB_MASK];
 
 	if (shift)
-		return p->qavg >> shift;
+		return v->qavg >> shift;
 	else {
 		/* Approximate initial part of exponent with linear function:
 		 *
@@ -257,16 +263,17 @@  static inline unsigned long red_calc_qavg_from_idle_time(const struct red_parms
 		 * Seems, it is the best solution to
 		 * problem of too coarse exponent tabulation.
 		 */
-		us_idle = (p->qavg * (u64)us_idle) >> p->Scell_log;
+		us_idle = (v->qavg * (u64)us_idle) >> p->Scell_log;
 
-		if (us_idle < (p->qavg >> 1))
-			return p->qavg - us_idle;
+		if (us_idle < (v->qavg >> 1))
+			return v->qavg - us_idle;
 		else
-			return p->qavg >> 1;
+			return v->qavg >> 1;
 	}
 }
 
 static inline unsigned long red_calc_qavg_no_idle_time(const struct red_parms *p,
+						       const struct red_vars *v,
 						       unsigned int backlog)
 {
 	/*
@@ -278,16 +285,17 @@  static inline unsigned long red_calc_qavg_no_idle_time(const struct red_parms *p
 	 *
 	 * --ANK (980924)
 	 */
-	return p->qavg + (backlog - (p->qavg >> p->Wlog));
+	return v->qavg + (backlog - (v->qavg >> p->Wlog));
 }
 
 static inline unsigned long red_calc_qavg(const struct red_parms *p,
+					  const struct red_vars *v,
 					  unsigned int backlog)
 {
-	if (!red_is_idling(p))
-		return red_calc_qavg_no_idle_time(p, backlog);
+	if (!red_is_idling(v))
+		return red_calc_qavg_no_idle_time(p, v, backlog);
 	else
-		return red_calc_qavg_from_idle_time(p);
+		return red_calc_qavg_from_idle_time(p, v);
 }
 
 
@@ -296,7 +304,9 @@  static inline u32 red_random(const struct red_parms *p)
 	return reciprocal_divide(net_random(), p->max_P_reciprocal);
 }
 
-static inline int red_mark_probability(const struct red_parms *p, unsigned long qavg)
+static inline int red_mark_probability(const struct red_parms *p,
+				       const struct red_vars *v,
+				       unsigned long qavg)
 {
 	/* The formula used below causes questions.
 
@@ -314,7 +324,7 @@  static inline int red_mark_probability(const struct red_parms *p, unsigned long
 
 	   Any questions? --ANK (980924)
 	 */
-	return !(((qavg - p->qth_min) >> p->Wlog) * p->qcount < p->qR);
+	return !(((qavg - p->qth_min) >> p->Wlog) * v->qcount < v->qR);
 }
 
 enum {
@@ -323,7 +333,7 @@  enum {
 	RED_ABOVE_MAX_TRESH,
 };
 
-static inline int red_cmp_thresh(struct red_parms *p, unsigned long qavg)
+static inline int red_cmp_thresh(const struct red_parms *p, unsigned long qavg)
 {
 	if (qavg < p->qth_min)
 		return RED_BELOW_MIN_THRESH;
@@ -339,27 +349,29 @@  enum {
 	RED_HARD_MARK,
 };
 
-static inline int red_action(struct red_parms *p, unsigned long qavg)
+static inline int red_action(const struct red_parms *p,
+			     struct red_vars *v,
+			     unsigned long qavg)
 {
 	switch (red_cmp_thresh(p, qavg)) {
 		case RED_BELOW_MIN_THRESH:
-			p->qcount = -1;
+			v->qcount = -1;
 			return RED_DONT_MARK;
 
 		case RED_BETWEEN_TRESH:
-			if (++p->qcount) {
-				if (red_mark_probability(p, qavg)) {
-					p->qcount = 0;
-					p->qR = red_random(p);
+			if (++v->qcount) {
+				if (red_mark_probability(p, v, qavg)) {
+					v->qcount = 0;
+					v->qR = red_random(p);
 					return RED_PROB_MARK;
 				}
 			} else
-				p->qR = red_random(p);
+				v->qR = red_random(p);
 
 			return RED_DONT_MARK;
 
 		case RED_ABOVE_MAX_TRESH:
-			p->qcount = -1;
+			v->qcount = -1;
 			return RED_HARD_MARK;
 	}
 
@@ -367,14 +379,14 @@  static inline int red_action(struct red_parms *p, unsigned long qavg)
 	return RED_DONT_MARK;
 }
 
-static inline void red_adaptative_algo(struct red_parms *p)
+static inline void red_adaptative_algo(struct red_parms *p, struct red_vars *v)
 {
 	unsigned long qavg;
 	u32 max_p_delta;
 
-	qavg = p->qavg;
-	if (red_is_idling(p))
-		qavg = red_calc_qavg_from_idle_time(p);
+	qavg = v->qavg;
+	if (red_is_idling(v))
+		qavg = red_calc_qavg_from_idle_time(p, v);
 
 	/* p->qavg is fixed point number with point at Wlog */
 	qavg >>= p->Wlog;
diff --git a/net/sched/sch_choke.c b/net/sched/sch_choke.c
index bef00ac..e465064 100644
--- a/net/sched/sch_choke.c
+++ b/net/sched/sch_choke.c
@@ -57,6 +57,7 @@  struct choke_sched_data {
 	struct red_parms parms;
 
 /* Variables */
+	struct red_vars  vars;
 	struct tcf_proto *filter_list;
 	struct {
 		u32	prob_drop;	/* Early probability drops */
@@ -265,7 +266,7 @@  static bool choke_match_random(const struct choke_sched_data *q,
 static int choke_enqueue(struct sk_buff *skb, struct Qdisc *sch)
 {
 	struct choke_sched_data *q = qdisc_priv(sch);
-	struct red_parms *p = &q->parms;
+	const struct red_parms *p = &q->parms;
 	int ret = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
 
 	if (q->filter_list) {
@@ -276,13 +277,13 @@  static int choke_enqueue(struct sk_buff *skb, struct Qdisc *sch)
 
 	choke_skb_cb(skb)->keys_valid = 0;
 	/* Compute average queue usage (see RED) */
-	p->qavg = red_calc_qavg(p, sch->q.qlen);
-	if (red_is_idling(p))
-		red_end_of_idle_period(p);
+	q->vars.qavg = red_calc_qavg(p, &q->vars, sch->q.qlen);
+	if (red_is_idling(&q->vars))
+		red_end_of_idle_period(&q->vars);
 
 	/* Is queue small? */
-	if (p->qavg <= p->qth_min)
-		p->qcount = -1;
+	if (q->vars.qavg <= p->qth_min)
+		q->vars.qcount = -1;
 	else {
 		unsigned int idx;
 
@@ -294,8 +295,8 @@  static int choke_enqueue(struct sk_buff *skb, struct Qdisc *sch)
 		}
 
 		/* Queue is large, always mark/drop */
-		if (p->qavg > p->qth_max) {
-			p->qcount = -1;
+		if (q->vars.qavg > p->qth_max) {
+			q->vars.qcount = -1;
 
 			sch->qstats.overlimits++;
 			if (use_harddrop(q) || !use_ecn(q) ||
@@ -305,10 +306,10 @@  static int choke_enqueue(struct sk_buff *skb, struct Qdisc *sch)
 			}
 
 			q->stats.forced_mark++;
-		} else if (++p->qcount) {
-			if (red_mark_probability(p, p->qavg)) {
-				p->qcount = 0;
-				p->qR = red_random(p);
+		} else if (++q->vars.qcount) {
+			if (red_mark_probability(p, &q->vars, q->vars.qavg)) {
+				q->vars.qcount = 0;
+				q->vars.qR = red_random(p);
 
 				sch->qstats.overlimits++;
 				if (!use_ecn(q) || !INET_ECN_set_ce(skb)) {
@@ -319,7 +320,7 @@  static int choke_enqueue(struct sk_buff *skb, struct Qdisc *sch)
 				q->stats.prob_mark++;
 			}
 		} else
-			p->qR = red_random(p);
+			q->vars.qR = red_random(p);
 	}
 
 	/* Admit new packet */
@@ -353,8 +354,8 @@  static struct sk_buff *choke_dequeue(struct Qdisc *sch)
 	struct sk_buff *skb;
 
 	if (q->head == q->tail) {
-		if (!red_is_idling(&q->parms))
-			red_start_of_idle_period(&q->parms);
+		if (!red_is_idling(&q->vars))
+			red_start_of_idle_period(&q->vars);
 		return NULL;
 	}
 
@@ -377,8 +378,8 @@  static unsigned int choke_drop(struct Qdisc *sch)
 	if (len > 0)
 		q->stats.other++;
 	else {
-		if (!red_is_idling(&q->parms))
-			red_start_of_idle_period(&q->parms);
+		if (!red_is_idling(&q->vars))
+			red_start_of_idle_period(&q->vars);
 	}
 
 	return len;
@@ -388,7 +389,7 @@  static void choke_reset(struct Qdisc *sch)
 {
 	struct choke_sched_data *q = qdisc_priv(sch);
 
-	red_restart(&q->parms);
+	red_restart(&q->vars);
 }
 
 static const struct nla_policy choke_policy[TCA_CHOKE_MAX + 1] = {
@@ -482,9 +483,10 @@  static int choke_change(struct Qdisc *sch, struct nlattr *opt)
 		      ctl->Plog, ctl->Scell_log,
 		      nla_data(tb[TCA_CHOKE_STAB]),
 		      max_P);
+	red_set_vars(&q->vars);
 
 	if (q->head == q->tail)
-		red_end_of_idle_period(&q->parms);
+		red_end_of_idle_period(&q->vars);
 
 	sch_tree_unlock(sch);
 	choke_free(old);
diff --git a/net/sched/sch_gred.c b/net/sched/sch_gred.c
index 53204de..0b15236 100644
--- a/net/sched/sch_gred.c
+++ b/net/sched/sch_gred.c
@@ -41,6 +41,7 @@  struct gred_sched_data {
 	u8		prio;		/* the prio of this vq */
 
 	struct red_parms parms;
+	struct red_vars  vars;
 	struct red_stats stats;
 };
 
@@ -55,7 +56,7 @@  struct gred_sched {
 	u32		red_flags;
 	u32 		DPs;
 	u32 		def;
-	struct red_parms wred_set;
+	struct red_vars wred_set;
 };
 
 static inline int gred_wred_mode(struct gred_sched *table)
@@ -125,17 +126,17 @@  static inline u16 tc_index_to_dp(struct sk_buff *skb)
 	return skb->tc_index & GRED_VQ_MASK;
 }
 
-static inline void gred_load_wred_set(struct gred_sched *table,
+static inline void gred_load_wred_set(const struct gred_sched *table,
 				      struct gred_sched_data *q)
 {
-	q->parms.qavg = table->wred_set.qavg;
-	q->parms.qidlestart = table->wred_set.qidlestart;
+	q->vars.qavg = table->wred_set.qavg;
+	q->vars.qidlestart = table->wred_set.qidlestart;
 }
 
 static inline void gred_store_wred_set(struct gred_sched *table,
 				       struct gred_sched_data *q)
 {
-	table->wred_set.qavg = q->parms.qavg;
+	table->wred_set.qavg = q->vars.qavg;
 }
 
 static inline int gred_use_ecn(struct gred_sched *t)
@@ -170,7 +171,7 @@  static int gred_enqueue(struct sk_buff *skb, struct Qdisc *sch)
 				goto drop;
 		}
 
-		/* fix tc_index? --could be controvesial but needed for
+		/* fix tc_index? --could be controversial but needed for
 		   requeueing */
 		skb->tc_index = (skb->tc_index & ~GRED_VQ_MASK) | dp;
 	}
@@ -181,8 +182,8 @@  static int gred_enqueue(struct sk_buff *skb, struct Qdisc *sch)
 
 		for (i = 0; i < t->DPs; i++) {
 			if (t->tab[i] && t->tab[i]->prio < q->prio &&
-			    !red_is_idling(&t->tab[i]->parms))
-				qavg += t->tab[i]->parms.qavg;
+			    !red_is_idling(&t->tab[i]->vars))
+				qavg += t->tab[i]->vars.qavg;
 		}
 
 	}
@@ -193,15 +194,17 @@  static int gred_enqueue(struct sk_buff *skb, struct Qdisc *sch)
 	if (gred_wred_mode(t))
 		gred_load_wred_set(t, q);
 
-	q->parms.qavg = red_calc_qavg(&q->parms, gred_backlog(t, q, sch));
+	q->vars.qavg = red_calc_qavg(&q->parms,
+				     &q->vars,
+				     gred_backlog(t, q, sch));
 
-	if (red_is_idling(&q->parms))
-		red_end_of_idle_period(&q->parms);
+	if (red_is_idling(&q->vars))
+		red_end_of_idle_period(&q->vars);
 
 	if (gred_wred_mode(t))
 		gred_store_wred_set(t, q);
 
-	switch (red_action(&q->parms, q->parms.qavg + qavg)) {
+	switch (red_action(&q->parms, &q->vars, q->vars.qavg + qavg)) {
 	case RED_DONT_MARK:
 		break;
 
@@ -260,7 +263,7 @@  static struct sk_buff *gred_dequeue(struct Qdisc *sch)
 			q->backlog -= qdisc_pkt_len(skb);
 
 			if (!q->backlog && !gred_wred_mode(t))
-				red_start_of_idle_period(&q->parms);
+				red_start_of_idle_period(&q->vars);
 		}
 
 		return skb;
@@ -293,7 +296,7 @@  static unsigned int gred_drop(struct Qdisc *sch)
 			q->stats.other++;
 
 			if (!q->backlog && !gred_wred_mode(t))
-				red_start_of_idle_period(&q->parms);
+				red_start_of_idle_period(&q->vars);
 		}
 
 		qdisc_drop(skb, sch);
@@ -320,7 +323,7 @@  static void gred_reset(struct Qdisc *sch)
 		if (!q)
 			continue;
 
-		red_restart(&q->parms);
+		red_restart(&q->vars);
 		q->backlog = 0;
 	}
 }
@@ -398,12 +401,12 @@  static inline int gred_change_vq(struct Qdisc *sch, int dp,
 	q->limit = ctl->limit;
 
 	if (q->backlog == 0)
-		red_end_of_idle_period(&q->parms);
+		red_end_of_idle_period(&q->vars);
 
 	red_set_parms(&q->parms,
 		      ctl->qth_min, ctl->qth_max, ctl->Wlog, ctl->Plog,
 		      ctl->Scell_log, stab, max_P);
-
+	red_set_vars(&q->vars);
 	return 0;
 }
 
@@ -563,12 +566,12 @@  static int gred_dump(struct Qdisc *sch, struct sk_buff *skb)
 		opt.bytesin	= q->bytesin;
 
 		if (gred_wred_mode(table)) {
-			q->parms.qidlestart =
-				table->tab[table->def]->parms.qidlestart;
-			q->parms.qavg = table->tab[table->def]->parms.qavg;
+			q->vars.qidlestart =
+				table->tab[table->def]->vars.qidlestart;
+			q->vars.qavg = table->tab[table->def]->vars.qavg;
 		}
 
-		opt.qave = red_calc_qavg(&q->parms, q->parms.qavg);
+		opt.qave = red_calc_qavg(&q->parms, &q->vars, q->vars.qavg);
 
 append_opt:
 		if (nla_append(skb, sizeof(opt), &opt) < 0)
diff --git a/net/sched/sch_red.c b/net/sched/sch_red.c
index ce2256a..a5cc301 100644
--- a/net/sched/sch_red.c
+++ b/net/sched/sch_red.c
@@ -41,6 +41,7 @@  struct red_sched_data {
 	unsigned char		flags;
 	struct timer_list	adapt_timer;
 	struct red_parms	parms;
+	struct red_vars		vars;
 	struct red_stats	stats;
 	struct Qdisc		*qdisc;
 };
@@ -61,12 +62,14 @@  static int red_enqueue(struct sk_buff *skb, struct Qdisc *sch)
 	struct Qdisc *child = q->qdisc;
 	int ret;
 
-	q->parms.qavg = red_calc_qavg(&q->parms, child->qstats.backlog);
+	q->vars.qavg = red_calc_qavg(&q->parms,
+				     &q->vars,
+				     child->qstats.backlog);
 
-	if (red_is_idling(&q->parms))
-		red_end_of_idle_period(&q->parms);
+	if (red_is_idling(&q->vars))
+		red_end_of_idle_period(&q->vars);
 
-	switch (red_action(&q->parms, q->parms.qavg)) {
+	switch (red_action(&q->parms, &q->vars, q->vars.qavg)) {
 	case RED_DONT_MARK:
 		break;
 
@@ -117,8 +120,8 @@  static struct sk_buff *red_dequeue(struct Qdisc *sch)
 		qdisc_bstats_update(sch, skb);
 		sch->q.qlen--;
 	} else {
-		if (!red_is_idling(&q->parms))
-			red_start_of_idle_period(&q->parms);
+		if (!red_is_idling(&q->vars))
+			red_start_of_idle_period(&q->vars);
 	}
 	return skb;
 }
@@ -144,8 +147,8 @@  static unsigned int red_drop(struct Qdisc *sch)
 		return len;
 	}
 
-	if (!red_is_idling(&q->parms))
-		red_start_of_idle_period(&q->parms);
+	if (!red_is_idling(&q->vars))
+		red_start_of_idle_period(&q->vars);
 
 	return 0;
 }
@@ -156,7 +159,7 @@  static void red_reset(struct Qdisc *sch)
 
 	qdisc_reset(q->qdisc);
 	sch->q.qlen = 0;
-	red_restart(&q->parms);
+	red_restart(&q->vars);
 }
 
 static void red_destroy(struct Qdisc *sch)
@@ -212,17 +215,19 @@  static int red_change(struct Qdisc *sch, struct nlattr *opt)
 		q->qdisc = child;
 	}
 
-	red_set_parms(&q->parms, ctl->qth_min, ctl->qth_max, ctl->Wlog,
+	red_set_parms(&q->parms,
+		      ctl->qth_min, ctl->qth_max, ctl->Wlog,
 		      ctl->Plog, ctl->Scell_log,
 		      nla_data(tb[TCA_RED_STAB]),
 		      max_P);
+	red_set_vars(&q->vars);
 
 	del_timer(&q->adapt_timer);
 	if (ctl->flags & TC_RED_ADAPTATIVE)
 		mod_timer(&q->adapt_timer, jiffies + HZ/2);
 
 	if (!q->qdisc->q.qlen)
-		red_start_of_idle_period(&q->parms);
+		red_start_of_idle_period(&q->vars);
 
 	sch_tree_unlock(sch);
 	return 0;
@@ -235,7 +240,7 @@  static inline void red_adaptative_timer(unsigned long arg)
 	spinlock_t *root_lock = qdisc_lock(qdisc_root_sleeping(sch));
 
 	spin_lock(root_lock);
-	red_adaptative_algo(&q->parms);
+	red_adaptative_algo(&q->parms, &q->vars);
 	mod_timer(&q->adapt_timer, jiffies + HZ/2);
 	spin_unlock(root_lock);
 }