Commit b8b9618a authored by David S. Miller's avatar David S. Miller
Browse files

Merge branch 'net-sched-gred-introduce-per-virtual-queue-attributes' 



Jakub Kicinski says:

====================
net: sched: gred: introduce per-virtual queue attributes

This series updates the GRED Qdisc.  The Qdisc matches nfp offload very
well, but before we can offload it there are a number of improvements
to make.

First few patches add extack messages to the Qdisc and pass extack
to netlink validation.

Next a new netlink attribute group is added, to allow GRED to be
extended more easily.  Currently GRED passes C structures as attributes,
and even an array of C structs for virtual queue configuration.  User
space has hard coded the expected length of that array, so adding new
fields is not possible.

New two-level attribute group is added:

  [TCA_GRED_VQ_LIST]
    [TCA_GRED_VQ_ENTRY]
      [TCA_GRED_VQ_DP]
      [TCA_GRED_VQ_FLAGS]
      [TCA_GRED_VQ_STAT_*]
    [TCA_GRED_VQ_ENTRY]
      [TCA_GRED_VQ_DP]
      [TCA_GRED_VQ_FLAGS]
      [TCA_GRED_VQ_STAT_*]
    [TCA_GRED_VQ_ENTRY]
       ...

Statistics are dump only. Patch 4 switches the byte counts to be 64 bit,
and patch 5 introduces the new stats attributes for dump.  Patch 6
switches RED flags to be per-virtual queue, and patch 7 allows them
to be dumped and set at virtual queue granularity.
====================

Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parents 9c549a6b 72111015

include/uapi/linux/pkt_sched.h

+27 −0
Original line number Diff line number Diff line
@@ -291,11 +291,38 @@ enum { 
       TCA_GRED_DPS,

       TCA_GRED_MAX_P,

       TCA_GRED_LIMIT,

       TCA_GRED_VQ_LIST,	/* nested TCA_GRED_VQ_ENTRY */

       __TCA_GRED_MAX,

};



#define TCA_GRED_MAX (__TCA_GRED_MAX - 1)



enum {

	TCA_GRED_VQ_ENTRY_UNSPEC,

	TCA_GRED_VQ_ENTRY,	/* nested TCA_GRED_VQ_* */

	__TCA_GRED_VQ_ENTRY_MAX,

};

#define TCA_GRED_VQ_ENTRY_MAX (__TCA_GRED_VQ_ENTRY_MAX - 1)



enum {

	TCA_GRED_VQ_UNSPEC,

	TCA_GRED_VQ_PAD,

	TCA_GRED_VQ_DP,			/* u32 */

	TCA_GRED_VQ_STAT_BYTES,		/* u64 */

	TCA_GRED_VQ_STAT_PACKETS,	/* u32 */

	TCA_GRED_VQ_STAT_BACKLOG,	/* u32 */

	TCA_GRED_VQ_STAT_PROB_DROP,	/* u32 */

	TCA_GRED_VQ_STAT_PROB_MARK,	/* u32 */

	TCA_GRED_VQ_STAT_FORCED_DROP,	/* u32 */

	TCA_GRED_VQ_STAT_FORCED_MARK,	/* u32 */

	TCA_GRED_VQ_STAT_PDROP,		/* u32 */

	TCA_GRED_VQ_STAT_OTHER,		/* u32 */

	TCA_GRED_VQ_FLAGS,		/* u32 */

	__TCA_GRED_VQ_MAX

};



#define TCA_GRED_VQ_MAX (__TCA_GRED_VQ_MAX - 1)



struct tc_gred_qopt {

	__u32		limit;        /* HARD maximal queue length (bytes)    */

	__u32		qth_min;      /* Min average length threshold (bytes) */

net/sched/sch_gred.c

+254 −27
Original line number Diff line number Diff line
@@ -29,13 +29,16 @@ 
#define GRED_DEF_PRIO (MAX_DPs / 2)

#define GRED_VQ_MASK (MAX_DPs - 1)



#define GRED_VQ_RED_FLAGS	(TC_RED_ECN | TC_RED_HARDDROP)



struct gred_sched_data;

struct gred_sched;



struct gred_sched_data {

	u32		limit;		/* HARD maximal queue length	*/

	u32		DP;		/* the drop parameters */

	u32		bytesin;	/* bytes seen on virtualQ so far*/

	u32		red_flags;	/* virtualQ version of red_flags */

	u64		bytesin;	/* bytes seen on virtualQ so far*/

	u32		packetsin;	/* packets seen on virtualQ so far*/

	u32		backlog;	/* bytes on the virtualQ */

	u8		prio;		/* the prio of this vq */
@@ -139,14 +142,27 @@ static inline void gred_store_wred_set(struct gred_sched *table, 
	table->wred_set.qidlestart = q->vars.qidlestart;

}



static inline int gred_use_ecn(struct gred_sched *t)

static int gred_use_ecn(struct gred_sched_data *q)

{

	return t->red_flags & TC_RED_ECN;

	return q->red_flags & TC_RED_ECN;

}



static inline int gred_use_harddrop(struct gred_sched *t)

static int gred_use_harddrop(struct gred_sched_data *q)

{

	return t->red_flags & TC_RED_HARDDROP;

	return q->red_flags & TC_RED_HARDDROP;

}



static bool gred_per_vq_red_flags_used(struct gred_sched *table)

{

	unsigned int i;



	/* Local per-vq flags couldn't have been set unless global are 0 */

	if (table->red_flags)

		return false;

	for (i = 0; i < MAX_DPs; i++)

		if (table->tab[i] && table->tab[i]->red_flags)

			return true;

	return false;

}



static int gred_enqueue(struct sk_buff *skb, struct Qdisc *sch,
@@ -212,7 +228,7 @@ static int gred_enqueue(struct sk_buff *skb, struct Qdisc *sch, 


	case RED_PROB_MARK:

		qdisc_qstats_overlimit(sch);

		if (!gred_use_ecn(t) || !INET_ECN_set_ce(skb)) {

		if (!gred_use_ecn(q) || !INET_ECN_set_ce(skb)) {

			q->stats.prob_drop++;

			goto congestion_drop;

		}
@@ -222,7 +238,7 @@ static int gred_enqueue(struct sk_buff *skb, struct Qdisc *sch, 


	case RED_HARD_MARK:

		qdisc_qstats_overlimit(sch);

		if (gred_use_harddrop(t) || !gred_use_ecn(t) ||

		if (gred_use_harddrop(q) || !gred_use_ecn(q) ||

		    !INET_ECN_set_ce(skb)) {

			q->stats.forced_drop++;

			goto congestion_drop;
@@ -300,10 +316,12 @@ static inline void gred_destroy_vq(struct gred_sched_data *q) 
	kfree(q);

}



static inline int gred_change_table_def(struct Qdisc *sch, struct nlattr *dps)

static int gred_change_table_def(struct Qdisc *sch, struct nlattr *dps,

				 struct netlink_ext_ack *extack)

{

	struct gred_sched *table = qdisc_priv(sch);

	struct tc_gred_sopt *sopt;

	bool red_flags_changed;

	int i;



	if (!dps)
@@ -311,13 +329,28 @@ static inline int gred_change_table_def(struct Qdisc *sch, struct nlattr *dps) 


	sopt = nla_data(dps);



	if (sopt->DPs > MAX_DPs || sopt->DPs == 0 ||

	    sopt->def_DP >= sopt->DPs)

	if (sopt->DPs > MAX_DPs) {

		NL_SET_ERR_MSG_MOD(extack, "number of virtual queues too high");

		return -EINVAL;

	}

	if (sopt->DPs == 0) {

		NL_SET_ERR_MSG_MOD(extack,

				   "number of virtual queues can't be 0");

		return -EINVAL;

	}

	if (sopt->def_DP >= sopt->DPs) {

		NL_SET_ERR_MSG_MOD(extack, "default virtual queue above virtual queue count");

		return -EINVAL;

	}

	if (sopt->flags && gred_per_vq_red_flags_used(table)) {

		NL_SET_ERR_MSG_MOD(extack, "can't set per-Qdisc RED flags when per-virtual queue flags are used");

		return -EINVAL;

	}



	sch_tree_lock(sch);

	table->DPs = sopt->DPs;

	table->def = sopt->def_DP;

	red_flags_changed = table->red_flags != sopt->flags;

	table->red_flags = sopt->flags;



	/*
@@ -337,6 +370,12 @@ static inline int gred_change_table_def(struct Qdisc *sch, struct nlattr *dps) 
		gred_disable_wred_mode(table);

	}



	if (red_flags_changed)

		for (i = 0; i < table->DPs; i++)

			if (table->tab[i])

				table->tab[i]->red_flags =

					table->red_flags & GRED_VQ_RED_FLAGS;



	for (i = table->DPs; i < MAX_DPs; i++) {

		if (table->tab[i]) {

			pr_warn("GRED: Warning: Destroying shadowed VQ 0x%x\n",
@@ -352,19 +391,23 @@ static inline int gred_change_table_def(struct Qdisc *sch, struct nlattr *dps) 
static inline int gred_change_vq(struct Qdisc *sch, int dp,

				 struct tc_gred_qopt *ctl, int prio,

				 u8 *stab, u32 max_P,

				 struct gred_sched_data **prealloc)

				 struct gred_sched_data **prealloc,

				 struct netlink_ext_ack *extack)

{

	struct gred_sched *table = qdisc_priv(sch);

	struct gred_sched_data *q = table->tab[dp];



	if (!red_check_params(ctl->qth_min, ctl->qth_max, ctl->Wlog))

	if (!red_check_params(ctl->qth_min, ctl->qth_max, ctl->Wlog)) {

		NL_SET_ERR_MSG_MOD(extack, "invalid RED parameters");

		return -EINVAL;

	}



	if (!q) {

		table->tab[dp] = q = *prealloc;

		*prealloc = NULL;

		if (!q)

			return -ENOMEM;

		q->red_flags = table->red_flags & GRED_VQ_RED_FLAGS;

	}



	q->DP = dp;
@@ -384,14 +427,127 @@ static inline int gred_change_vq(struct Qdisc *sch, int dp, 
	return 0;

}



static const struct nla_policy gred_vq_policy[TCA_GRED_VQ_MAX + 1] = {

	[TCA_GRED_VQ_DP]	= { .type = NLA_U32 },

	[TCA_GRED_VQ_FLAGS]	= { .type = NLA_U32 },

};



static const struct nla_policy gred_vqe_policy[TCA_GRED_VQ_ENTRY_MAX + 1] = {

	[TCA_GRED_VQ_ENTRY]	= { .type = NLA_NESTED },

};



static const struct nla_policy gred_policy[TCA_GRED_MAX + 1] = {

	[TCA_GRED_PARMS]	= { .len = sizeof(struct tc_gred_qopt) },

	[TCA_GRED_STAB]		= { .len = 256 },

	[TCA_GRED_DPS]		= { .len = sizeof(struct tc_gred_sopt) },

	[TCA_GRED_MAX_P]	= { .type = NLA_U32 },

	[TCA_GRED_LIMIT]	= { .type = NLA_U32 },

	[TCA_GRED_VQ_LIST]	= { .type = NLA_NESTED },

};



static void gred_vq_apply(struct gred_sched *table, const struct nlattr *entry)

{

	struct nlattr *tb[TCA_GRED_VQ_MAX + 1];

	u32 dp;



	nla_parse_nested(tb, TCA_GRED_VQ_MAX, entry, gred_vq_policy, NULL);



	dp = nla_get_u32(tb[TCA_GRED_VQ_DP]);



	if (tb[TCA_GRED_VQ_FLAGS])

		table->tab[dp]->red_flags = nla_get_u32(tb[TCA_GRED_VQ_FLAGS]);

}



static void gred_vqs_apply(struct gred_sched *table, struct nlattr *vqs)

{

	const struct nlattr *attr;

	int rem;



	nla_for_each_nested(attr, vqs, rem) {

		switch (nla_type(attr)) {

		case TCA_GRED_VQ_ENTRY:

			gred_vq_apply(table, attr);

			break;

		}

	}

}



static int gred_vq_validate(struct gred_sched *table, u32 cdp,

			    const struct nlattr *entry,

			    struct netlink_ext_ack *extack)

{

	struct nlattr *tb[TCA_GRED_VQ_MAX + 1];

	int err;

	u32 dp;



	err = nla_parse_nested(tb, TCA_GRED_VQ_MAX, entry, gred_vq_policy,

			       extack);

	if (err < 0)

		return err;



	if (!tb[TCA_GRED_VQ_DP]) {

		NL_SET_ERR_MSG_MOD(extack, "Virtual queue with no index specified");

		return -EINVAL;

	}

	dp = nla_get_u32(tb[TCA_GRED_VQ_DP]);

	if (dp >= table->DPs) {

		NL_SET_ERR_MSG_MOD(extack, "Virtual queue with index out of bounds");

		return -EINVAL;

	}

	if (dp != cdp && !table->tab[dp]) {

		NL_SET_ERR_MSG_MOD(extack, "Virtual queue not yet instantiated");

		return -EINVAL;

	}



	if (tb[TCA_GRED_VQ_FLAGS]) {

		u32 red_flags = nla_get_u32(tb[TCA_GRED_VQ_FLAGS]);



		if (table->red_flags && table->red_flags != red_flags) {

			NL_SET_ERR_MSG_MOD(extack, "can't change per-virtual queue RED flags when per-Qdisc flags are used");

			return -EINVAL;

		}

		if (red_flags & ~GRED_VQ_RED_FLAGS) {

			NL_SET_ERR_MSG_MOD(extack,

					   "invalid RED flags specified");

			return -EINVAL;

		}

	}



	return 0;

}



static int gred_vqs_validate(struct gred_sched *table, u32 cdp,

			     struct nlattr *vqs, struct netlink_ext_ack *extack)

{

	const struct nlattr *attr;

	int rem, err;



	err = nla_validate_nested(vqs, TCA_GRED_VQ_ENTRY_MAX,

				  gred_vqe_policy, extack);

	if (err < 0)

		return err;



	nla_for_each_nested(attr, vqs, rem) {

		switch (nla_type(attr)) {

		case TCA_GRED_VQ_ENTRY:

			err = gred_vq_validate(table, cdp, attr, extack);

			if (err)

				return err;

			break;

		default:

			NL_SET_ERR_MSG_MOD(extack, "GRED_VQ_LIST can contain only entry attributes");

			return -EINVAL;

		}

	}



	if (rem > 0) {

		NL_SET_ERR_MSG_MOD(extack, "Trailing data after parsing virtual queue list");

		return -EINVAL;

	}



	return 0;

}



static int gred_change(struct Qdisc *sch, struct nlattr *opt,

		       struct netlink_ext_ack *extack)

{
@@ -406,29 +562,39 @@ static int gred_change(struct Qdisc *sch, struct nlattr *opt, 
	if (opt == NULL)

		return -EINVAL;



	err = nla_parse_nested(tb, TCA_GRED_MAX, opt, gred_policy, NULL);

	err = nla_parse_nested(tb, TCA_GRED_MAX, opt, gred_policy, extack);

	if (err < 0)

		return err;



	if (tb[TCA_GRED_PARMS] == NULL && tb[TCA_GRED_STAB] == NULL) {

		if (tb[TCA_GRED_LIMIT] != NULL)

			sch->limit = nla_get_u32(tb[TCA_GRED_LIMIT]);

		return gred_change_table_def(sch, tb[TCA_GRED_DPS]);

		return gred_change_table_def(sch, tb[TCA_GRED_DPS], extack);

	}



	if (tb[TCA_GRED_PARMS] == NULL ||

	    tb[TCA_GRED_STAB] == NULL ||

	    tb[TCA_GRED_LIMIT] != NULL)

	    tb[TCA_GRED_LIMIT] != NULL) {

		NL_SET_ERR_MSG_MOD(extack, "can't configure Qdisc and virtual queue at the same time");

		return -EINVAL;

	}



	max_P = tb[TCA_GRED_MAX_P] ? nla_get_u32(tb[TCA_GRED_MAX_P]) : 0;



	err = -EINVAL;

	ctl = nla_data(tb[TCA_GRED_PARMS]);

	stab = nla_data(tb[TCA_GRED_STAB]);



	if (ctl->DP >= table->DPs)

		goto errout;

	if (ctl->DP >= table->DPs) {

		NL_SET_ERR_MSG_MOD(extack, "virtual queue index above virtual queue count");

		return -EINVAL;

	}



	if (tb[TCA_GRED_VQ_LIST]) {

		err = gred_vqs_validate(table, ctl->DP, tb[TCA_GRED_VQ_LIST],

					extack);

		if (err)

			return err;

	}



	if (gred_rio_mode(table)) {

		if (ctl->prio == 0) {
@@ -448,9 +614,13 @@ static int gred_change(struct Qdisc *sch, struct nlattr *opt, 
	prealloc = kzalloc(sizeof(*prealloc), GFP_KERNEL);

	sch_tree_lock(sch);



	err = gred_change_vq(sch, ctl->DP, ctl, prio, stab, max_P, &prealloc);

	err = gred_change_vq(sch, ctl->DP, ctl, prio, stab, max_P, &prealloc,

			     extack);

	if (err < 0)

		goto errout_locked;

		goto err_unlock_free;



	if (tb[TCA_GRED_VQ_LIST])

		gred_vqs_apply(table, tb[TCA_GRED_VQ_LIST]);



	if (gred_rio_mode(table)) {

		gred_disable_wred_mode(table);
@@ -458,12 +628,13 @@ static int gred_change(struct Qdisc *sch, struct nlattr *opt, 
			gred_enable_wred_mode(table);

	}



	err = 0;

	sch_tree_unlock(sch);

	kfree(prealloc);

	return 0;



errout_locked:

err_unlock_free:

	sch_tree_unlock(sch);

	kfree(prealloc);

errout:

	return err;

}
@@ -476,12 +647,15 @@ static int gred_init(struct Qdisc *sch, struct nlattr *opt, 
	if (!opt)

		return -EINVAL;



	err = nla_parse_nested(tb, TCA_GRED_MAX, opt, gred_policy, NULL);

	err = nla_parse_nested(tb, TCA_GRED_MAX, opt, gred_policy, extack);

	if (err < 0)

		return err;



	if (tb[TCA_GRED_PARMS] || tb[TCA_GRED_STAB])

	if (tb[TCA_GRED_PARMS] || tb[TCA_GRED_STAB]) {

		NL_SET_ERR_MSG_MOD(extack,

				   "virtual queue configuration can't be specified at initialization time");

		return -EINVAL;

	}



	if (tb[TCA_GRED_LIMIT])

		sch->limit = nla_get_u32(tb[TCA_GRED_LIMIT]);
@@ -489,13 +663,13 @@ static int gred_init(struct Qdisc *sch, struct nlattr *opt, 
		sch->limit = qdisc_dev(sch)->tx_queue_len

		             * psched_mtu(qdisc_dev(sch));



	return gred_change_table_def(sch, tb[TCA_GRED_DPS]);

	return gred_change_table_def(sch, tb[TCA_GRED_DPS], extack);

}



static int gred_dump(struct Qdisc *sch, struct sk_buff *skb)

{

	struct gred_sched *table = qdisc_priv(sch);

	struct nlattr *parms, *opts = NULL;

	struct nlattr *parms, *vqs, *opts = NULL;

	int i;

	u32 max_p[MAX_DPs];

	struct tc_gred_sopt sopt = {
@@ -522,6 +696,7 @@ static int gred_dump(struct Qdisc *sch, struct sk_buff *skb) 
	if (nla_put_u32(skb, TCA_GRED_LIMIT, sch->limit))

		goto nla_put_failure;



	/* Old style all-in-one dump of VQs */

	parms = nla_nest_start(skb, TCA_GRED_PARMS);

	if (parms == NULL)

		goto nla_put_failure;
@@ -572,6 +747,58 @@ append_opt: 


	nla_nest_end(skb, parms);



	/* Dump the VQs again, in more structured way */

	vqs = nla_nest_start(skb, TCA_GRED_VQ_LIST);

	if (!vqs)

		goto nla_put_failure;



	for (i = 0; i < MAX_DPs; i++) {

		struct gred_sched_data *q = table->tab[i];

		struct nlattr *vq;



		if (!q)

			continue;



		vq = nla_nest_start(skb, TCA_GRED_VQ_ENTRY);

		if (!vq)

			goto nla_put_failure;



		if (nla_put_u32(skb, TCA_GRED_VQ_DP, q->DP))

			goto nla_put_failure;



		if (nla_put_u32(skb, TCA_GRED_VQ_FLAGS, q->red_flags))

			goto nla_put_failure;



		/* Stats */

		if (nla_put_u64_64bit(skb, TCA_GRED_VQ_STAT_BYTES, q->bytesin,

				      TCA_GRED_VQ_PAD))

			goto nla_put_failure;

		if (nla_put_u32(skb, TCA_GRED_VQ_STAT_PACKETS, q->packetsin))

			goto nla_put_failure;

		if (nla_put_u32(skb, TCA_GRED_VQ_STAT_BACKLOG,

				gred_backlog(table, q, sch)))

			goto nla_put_failure;

		if (nla_put_u32(skb, TCA_GRED_VQ_STAT_PROB_DROP,

				q->stats.prob_drop))

			goto nla_put_failure;

		if (nla_put_u32(skb, TCA_GRED_VQ_STAT_PROB_MARK,

				q->stats.prob_mark))

			goto nla_put_failure;

		if (nla_put_u32(skb, TCA_GRED_VQ_STAT_FORCED_DROP,

				q->stats.forced_drop))

			goto nla_put_failure;

		if (nla_put_u32(skb, TCA_GRED_VQ_STAT_FORCED_MARK,

				q->stats.forced_mark))

			goto nla_put_failure;

		if (nla_put_u32(skb, TCA_GRED_VQ_STAT_PDROP, q->stats.pdrop))

			goto nla_put_failure;

		if (nla_put_u32(skb, TCA_GRED_VQ_STAT_OTHER, q->stats.other))

			goto nla_put_failure;



		nla_nest_end(skb, vq);

	}

	nla_nest_end(skb, vqs);



	return nla_nest_end(skb, opts);



nla_put_failure:

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