Commit 70da9f0b authored by John Fastabend's avatar John Fastabend Committed by David S. Miller
Browse files

net: sched: cls_flow use RCU 



Signed-off-by: default avatarJohn Fastabend <john.r.fastabend@intel.com>
Acked-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 952313bd

net/sched/cls_flow.c

+84 −61
Original line number Diff line number Diff line
@@ -34,12 +34,14 @@ 


struct flow_head {

	struct list_head	filters;

	struct rcu_head		rcu;

};



struct flow_filter {

	struct list_head	list;

	struct tcf_exts		exts;

	struct tcf_ematch_tree	ematches;

	struct tcf_proto	*tp;

	struct timer_list	perturb_timer;

	u32			perturb_period;

	u32			handle;
@@ -54,6 +56,7 @@ struct flow_filter { 
	u32			divisor;

	u32			baseclass;

	u32			hashrnd;

	struct rcu_head		rcu;

};



static inline u32 addr_fold(void *addr)
@@ -276,14 +279,14 @@ static u32 flow_key_get(struct sk_buff *skb, int key, struct flow_keys *flow) 
static int flow_classify(struct sk_buff *skb, const struct tcf_proto *tp,

			 struct tcf_result *res)

{

	struct flow_head *head = tp->root;

	struct flow_head *head = rcu_dereference_bh(tp->root);

	struct flow_filter *f;

	u32 keymask;

	u32 classid;

	unsigned int n, key;

	int r;



	list_for_each_entry(f, &head->filters, list) {

	list_for_each_entry_rcu(f, &head->filters, list) {

		u32 keys[FLOW_KEY_MAX + 1];

		struct flow_keys flow_keys;
@@ -346,13 +349,23 @@ static const struct nla_policy flow_policy[TCA_FLOW_MAX + 1] = { 
	[TCA_FLOW_PERTURB]	= { .type = NLA_U32 },

};



static void flow_destroy_filter(struct rcu_head *head)

{

	struct flow_filter *f = container_of(head, struct flow_filter, rcu);



	del_timer_sync(&f->perturb_timer);

	tcf_exts_destroy(f->tp, &f->exts);

	tcf_em_tree_destroy(f->tp, &f->ematches);

	kfree(f);

}



static int flow_change(struct net *net, struct sk_buff *in_skb,

		       struct tcf_proto *tp, unsigned long base,

		       u32 handle, struct nlattr **tca,

		       unsigned long *arg, bool ovr)

{

	struct flow_head *head = tp->root;

	struct flow_filter *f;

	struct flow_head *head = rtnl_dereference(tp->root);

	struct flow_filter *fold, *fnew;

	struct nlattr *opt = tca[TCA_OPTIONS];

	struct nlattr *tb[TCA_FLOW_MAX + 1];

	struct tcf_exts e;
@@ -401,20 +414,42 @@ static int flow_change(struct net *net, struct sk_buff *in_skb, 
	if (err < 0)

		goto err1;



	f = (struct flow_filter *)*arg;

	if (f != NULL) {

	err = -ENOBUFS;

	fnew = kzalloc(sizeof(*fnew), GFP_KERNEL);

	if (!fnew)

		goto err2;



	fold = (struct flow_filter *)*arg;

	if (fold) {

		err = -EINVAL;

		if (f->handle != handle && handle)

		if (fold->handle != handle && handle)

			goto err2;



		mode = f->mode;

		/* Copy fold into fnew */

		fnew->handle = fold->handle;

		fnew->keymask = fold->keymask;

		fnew->tp = fold->tp;



		fnew->handle = fold->handle;

		fnew->nkeys = fold->nkeys;

		fnew->keymask = fold->keymask;

		fnew->mode = fold->mode;

		fnew->mask = fold->mask;

		fnew->xor = fold->xor;

		fnew->rshift = fold->rshift;

		fnew->addend = fold->addend;

		fnew->divisor = fold->divisor;

		fnew->baseclass = fold->baseclass;

		fnew->hashrnd = fold->hashrnd;



		mode = fold->mode;

		if (tb[TCA_FLOW_MODE])

			mode = nla_get_u32(tb[TCA_FLOW_MODE]);

		if (mode != FLOW_MODE_HASH && nkeys > 1)

			goto err2;



		if (mode == FLOW_MODE_HASH)

			perturb_period = f->perturb_period;

			perturb_period = fold->perturb_period;

		if (tb[TCA_FLOW_PERTURB]) {

			if (mode != FLOW_MODE_HASH)

				goto err2;
@@ -444,83 +479,70 @@ static int flow_change(struct net *net, struct sk_buff *in_skb, 
		if (TC_H_MIN(baseclass) == 0)

			baseclass = TC_H_MAKE(baseclass, 1);



		err = -ENOBUFS;

		f = kzalloc(sizeof(*f), GFP_KERNEL);

		if (f == NULL)

			goto err2;



		f->handle = handle;

		f->mask	  = ~0U;

		tcf_exts_init(&f->exts, TCA_FLOW_ACT, TCA_FLOW_POLICE);



		get_random_bytes(&f->hashrnd, 4);

		f->perturb_timer.function = flow_perturbation;

		f->perturb_timer.data = (unsigned long)f;

		init_timer_deferrable(&f->perturb_timer);

		fnew->handle = handle;

		fnew->mask  = ~0U;

		fnew->tp = tp;

		get_random_bytes(&fnew->hashrnd, 4);

		tcf_exts_init(&fnew->exts, TCA_FLOW_ACT, TCA_FLOW_POLICE);

	}



	tcf_exts_change(tp, &f->exts, &e);

	tcf_em_tree_change(tp, &f->ematches, &t);

	fnew->perturb_timer.function = flow_perturbation;

	fnew->perturb_timer.data = (unsigned long)fnew;

	init_timer_deferrable(&fnew->perturb_timer);



	tcf_tree_lock(tp);

	tcf_exts_change(tp, &fnew->exts, &e);

	tcf_em_tree_change(tp, &fnew->ematches, &t);



	if (tb[TCA_FLOW_KEYS]) {

		f->keymask = keymask;

		f->nkeys   = nkeys;

		fnew->keymask = keymask;

		fnew->nkeys   = nkeys;

	}



	f->mode = mode;

	fnew->mode = mode;



	if (tb[TCA_FLOW_MASK])

		f->mask = nla_get_u32(tb[TCA_FLOW_MASK]);

		fnew->mask = nla_get_u32(tb[TCA_FLOW_MASK]);

	if (tb[TCA_FLOW_XOR])

		f->xor = nla_get_u32(tb[TCA_FLOW_XOR]);

		fnew->xor = nla_get_u32(tb[TCA_FLOW_XOR]);

	if (tb[TCA_FLOW_RSHIFT])

		f->rshift = nla_get_u32(tb[TCA_FLOW_RSHIFT]);

		fnew->rshift = nla_get_u32(tb[TCA_FLOW_RSHIFT]);

	if (tb[TCA_FLOW_ADDEND])

		f->addend = nla_get_u32(tb[TCA_FLOW_ADDEND]);

		fnew->addend = nla_get_u32(tb[TCA_FLOW_ADDEND]);



	if (tb[TCA_FLOW_DIVISOR])

		f->divisor = nla_get_u32(tb[TCA_FLOW_DIVISOR]);

		fnew->divisor = nla_get_u32(tb[TCA_FLOW_DIVISOR]);

	if (baseclass)

		f->baseclass = baseclass;

		fnew->baseclass = baseclass;



	f->perturb_period = perturb_period;

	del_timer(&f->perturb_timer);

	fnew->perturb_period = perturb_period;

	if (perturb_period)

		mod_timer(&f->perturb_timer, jiffies + perturb_period);

		mod_timer(&fnew->perturb_timer, jiffies + perturb_period);



	if (*arg == 0)

		list_add_tail(&f->list, &head->filters);

		list_add_tail_rcu(&fnew->list, &head->filters);

	else

		list_replace_rcu(&fnew->list, &fold->list);



	tcf_tree_unlock(tp);

	*arg = (unsigned long)fnew;



	*arg = (unsigned long)f;

	if (fold)

		call_rcu(&fold->rcu, flow_destroy_filter);

	return 0;



err2:

	tcf_em_tree_destroy(tp, &t);

	kfree(fnew);

err1:

	tcf_exts_destroy(tp, &e);

	return err;

}



static void flow_destroy_filter(struct tcf_proto *tp, struct flow_filter *f)

{

	del_timer_sync(&f->perturb_timer);

	tcf_exts_destroy(tp, &f->exts);

	tcf_em_tree_destroy(tp, &f->ematches);

	kfree(f);

}



static int flow_delete(struct tcf_proto *tp, unsigned long arg)

{

	struct flow_filter *f = (struct flow_filter *)arg;



	tcf_tree_lock(tp);

	list_del(&f->list);

	tcf_tree_unlock(tp);

	flow_destroy_filter(tp, f);

	list_del_rcu(&f->list);

	call_rcu(&f->rcu, flow_destroy_filter);

	return 0;

}
@@ -532,28 +554,29 @@ static int flow_init(struct tcf_proto *tp) 
	if (head == NULL)

		return -ENOBUFS;

	INIT_LIST_HEAD(&head->filters);

	tp->root = head;

	rcu_assign_pointer(tp->root, head);

	return 0;

}



static void flow_destroy(struct tcf_proto *tp)

{

	struct flow_head *head = tp->root;

	struct flow_head *head = rtnl_dereference(tp->root);

	struct flow_filter *f, *next;



	list_for_each_entry_safe(f, next, &head->filters, list) {

		list_del(&f->list);

		flow_destroy_filter(tp, f);

		list_del_rcu(&f->list);

		call_rcu(&f->rcu, flow_destroy_filter);

	}

	kfree(head);

	RCU_INIT_POINTER(tp->root, NULL);

	kfree_rcu(head, rcu);

}



static unsigned long flow_get(struct tcf_proto *tp, u32 handle)

{

	struct flow_head *head = tp->root;

	struct flow_head *head = rtnl_dereference(tp->root);

	struct flow_filter *f;



	list_for_each_entry(f, &head->filters, list)

	list_for_each_entry_rcu(f, &head->filters, list)

		if (f->handle == handle)

			return (unsigned long)f;

	return 0;
@@ -626,10 +649,10 @@ static int flow_dump(struct net *net, struct tcf_proto *tp, unsigned long fh, 


static void flow_walk(struct tcf_proto *tp, struct tcf_walker *arg)

{

	struct flow_head *head = tp->root;

	struct flow_head *head = rtnl_dereference(tp->root);

	struct flow_filter *f;



	list_for_each_entry(f, &head->filters, list) {

	list_for_each_entry_rcu(f, &head->filters, list) {

		if (arg->count < arg->skip)

			goto skip;

		if (arg->fn(tp, (unsigned long)f, arg) < 0) {