Commit e35a8ee5 authored by John Fastabend's avatar John Fastabend Committed by David S. Miller
Browse files

net: sched: fw use RCU 



RCU'ify fw classifier.

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 70da9f0b

net/sched/cls_fw.c

+77 −34
Original line number Diff line number Diff line
@@ -33,17 +33,20 @@ 


struct fw_head {

	u32			mask;

	struct fw_filter	*ht[HTSIZE];

	struct fw_filter __rcu	*ht[HTSIZE];

	struct rcu_head		rcu;

};



struct fw_filter {

	struct fw_filter	*next;

	struct fw_filter __rcu	*next;

	u32			id;

	struct tcf_result	res;

#ifdef CONFIG_NET_CLS_IND

	int			ifindex;

#endif /* CONFIG_NET_CLS_IND */

	struct tcf_exts		exts;

	struct tcf_proto	*tp;

	struct rcu_head		rcu;

};



static u32 fw_hash(u32 handle)
@@ -56,14 +59,16 @@ static u32 fw_hash(u32 handle) 
static int fw_classify(struct sk_buff *skb, const struct tcf_proto *tp,

			  struct tcf_result *res)

{

	struct fw_head *head = tp->root;

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

	struct fw_filter *f;

	int r;

	u32 id = skb->mark;



	if (head != NULL) {

		id &= head->mask;

		for (f = head->ht[fw_hash(id)]; f; f = f->next) {



		for (f = rcu_dereference_bh(head->ht[fw_hash(id)]); f;

		     f = rcu_dereference_bh(f->next)) {

			if (f->id == id) {

				*res = f->res;

#ifdef CONFIG_NET_CLS_IND
@@ -92,13 +97,14 @@ static int fw_classify(struct sk_buff *skb, const struct tcf_proto *tp, 


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

{

	struct fw_head *head = tp->root;

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

	struct fw_filter *f;



	if (head == NULL)

		return 0;



	for (f = head->ht[fw_hash(handle)]; f; f = f->next) {

	f = rtnl_dereference(head->ht[fw_hash(handle)]);

	for (; f; f = rtnl_dereference(f->next)) {

		if (f->id == handle)

			return (unsigned long)f;

	}
@@ -114,8 +120,11 @@ static int fw_init(struct tcf_proto *tp) 
	return 0;

}



static void fw_delete_filter(struct tcf_proto *tp, struct fw_filter *f)

static void fw_delete_filter(struct rcu_head *head)

{

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

	struct tcf_proto *tp = f->tp;



	tcf_unbind_filter(tp, &f->res);

	tcf_exts_destroy(tp, &f->exts);

	kfree(f);
@@ -123,7 +132,7 @@ static void fw_delete_filter(struct tcf_proto *tp, struct fw_filter *f) 


static void fw_destroy(struct tcf_proto *tp)

{

	struct fw_head *head = tp->root;

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

	struct fw_filter *f;

	int h;
@@ -131,29 +140,33 @@ static void fw_destroy(struct tcf_proto *tp) 
		return;



	for (h = 0; h < HTSIZE; h++) {

		while ((f = head->ht[h]) != NULL) {

			head->ht[h] = f->next;

			fw_delete_filter(tp, f);

		while ((f = rtnl_dereference(head->ht[h])) != NULL) {

			RCU_INIT_POINTER(head->ht[h],

					 rtnl_dereference(f->next));

			call_rcu(&f->rcu, fw_delete_filter);

		}

	}

	kfree(head);

	RCU_INIT_POINTER(tp->root, NULL);

	kfree_rcu(head, rcu);

}



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

{

	struct fw_head *head = tp->root;

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

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

	struct fw_filter **fp;

	struct fw_filter __rcu **fp;

	struct fw_filter *pfp;



	if (head == NULL || f == NULL)

		goto out;



	for (fp = &head->ht[fw_hash(f->id)]; *fp; fp = &(*fp)->next) {

		if (*fp == f) {

			tcf_tree_lock(tp);

			*fp = f->next;

			tcf_tree_unlock(tp);

			fw_delete_filter(tp, f);

	fp = &head->ht[fw_hash(f->id)];



	for (pfp = rtnl_dereference(*fp); pfp;

	     fp = &pfp->next, pfp = rtnl_dereference(*fp)) {

		if (pfp == f) {

			RCU_INIT_POINTER(*fp, rtnl_dereference(f->next));

			call_rcu(&f->rcu, fw_delete_filter);

			return 0;

		}

	}
@@ -171,7 +184,7 @@ static int 
fw_change_attrs(struct net *net, struct tcf_proto *tp, struct fw_filter *f,

	struct nlattr **tb, struct nlattr **tca, unsigned long base, bool ovr)

{

	struct fw_head *head = tp->root;

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

	struct tcf_exts e;

	u32 mask;

	int err;
@@ -220,7 +233,7 @@ static int fw_change(struct net *net, struct sk_buff *in_skb, 
		     struct nlattr **tca,

		     unsigned long *arg, bool ovr)

{

	struct fw_head *head = tp->root;

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

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

	struct nlattr *opt = tca[TCA_OPTIONS];

	struct nlattr *tb[TCA_FW_MAX + 1];
@@ -233,10 +246,42 @@ static int fw_change(struct net *net, struct sk_buff *in_skb, 
	if (err < 0)

		return err;



	if (f != NULL) {

	if (f) {

		struct fw_filter *pfp, *fnew;

		struct fw_filter __rcu **fp;



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

			return -EINVAL;

		return fw_change_attrs(net, tp, f, tb, tca, base, ovr);



		fnew = kzalloc(sizeof(struct fw_filter), GFP_KERNEL);

		if (!fnew)

			return -ENOBUFS;



		fnew->id = f->id;

		fnew->res = f->res;

#ifdef CONFIG_NET_CLS_IND

		fnew->ifindex = f->ifindex;

#endif /* CONFIG_NET_CLS_IND */

		fnew->tp = f->tp;



		err = fw_change_attrs(net, tp, fnew, tb, tca, base, ovr);

		if (err < 0) {

			kfree(fnew);

			return err;

		}



		fp = &head->ht[fw_hash(fnew->id)];

		for (pfp = rtnl_dereference(*fp); pfp;

		     fp = &pfp->next, pfp = rtnl_dereference(*fp))

			if (pfp == f)

				break;



		RCU_INIT_POINTER(fnew->next, rtnl_dereference(pfp->next));

		rcu_assign_pointer(*fp, fnew);

		call_rcu(&f->rcu, fw_delete_filter);



		*arg = (unsigned long)fnew;

		return err;

	}



	if (!handle)
@@ -252,9 +297,7 @@ static int fw_change(struct net *net, struct sk_buff *in_skb, 
			return -ENOBUFS;

		head->mask = mask;



		tcf_tree_lock(tp);

		tp->root = head;

		tcf_tree_unlock(tp);

		rcu_assign_pointer(tp->root, head);

	}



	f = kzalloc(sizeof(struct fw_filter), GFP_KERNEL);
@@ -263,15 +306,14 @@ static int fw_change(struct net *net, struct sk_buff *in_skb, 


	tcf_exts_init(&f->exts, TCA_FW_ACT, TCA_FW_POLICE);

	f->id = handle;

	f->tp = tp;



	err = fw_change_attrs(net, tp, f, tb, tca, base, ovr);

	if (err < 0)

		goto errout;



	f->next = head->ht[fw_hash(handle)];

	tcf_tree_lock(tp);

	head->ht[fw_hash(handle)] = f;

	tcf_tree_unlock(tp);

	RCU_INIT_POINTER(f->next, head->ht[fw_hash(handle)]);

	rcu_assign_pointer(head->ht[fw_hash(handle)], f);



	*arg = (unsigned long)f;

	return 0;
@@ -283,7 +325,7 @@ static int fw_change(struct net *net, struct sk_buff *in_skb, 


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

{

	struct fw_head *head = tp->root;

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

	int h;



	if (head == NULL)
@@ -295,7 +337,8 @@ static void fw_walk(struct tcf_proto *tp, struct tcf_walker *arg) 
	for (h = 0; h < HTSIZE; h++) {

		struct fw_filter *f;



		for (f = head->ht[h]; f; f = f->next) {

		for (f = rtnl_dereference(head->ht[h]); f;

		     f = rtnl_dereference(f->next)) {

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

				arg->count++;

				continue;
@@ -312,7 +355,7 @@ static void fw_walk(struct tcf_proto *tp, struct tcf_walker *arg) 
static int fw_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,

		   struct sk_buff *skb, struct tcmsg *t)

{

	struct fw_head *head = tp->root;

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

	struct fw_filter *f = (struct fw_filter *)fh;

	unsigned char *b = skb_tail_pointer(skb);

	struct nlattr *nest;