leandrof/linux
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

net_sched: red: split red_parms into parms and vars

Browse Source 
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>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2012-01-05 02:25:16 +00:00 committed by David S. Miller
parent 18cb809850
commit eeca6688d6
4 changed files with 117 additions and 95 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

98
include/net/red.h
View File

@ -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;

40
net/sched/sch_choke.c
View File

@ -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);

45
net/sched/sch_gred.c
View File

@ -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)

29
net/sched/sch_red.c
View File

@ -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);
}