Commit e98e4456 authored by Eyal Birger's avatar Eyal Birger Committed by Steffen Klassert
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xfrm interface: store xfrmi contexts in a hash by if_id 



xfrmi_lookup() is called on every packet. Using a single list for
looking up if_id becomes a bottleneck when having many xfrm interfaces.

Signed-off-by: default avatarEyal Birger <eyal.birger@gmail.com>
Signed-off-by: default avatarSteffen Klassert <steffen.klassert@secunet.com>
parent 2749c697

net/xfrm/xfrm_interface.c

+20 −9
Original line number Diff line number Diff line
@@ -49,20 +49,28 @@ static struct rtnl_link_ops xfrmi_link_ops __read_mostly; 
static unsigned int xfrmi_net_id __read_mostly;

static const struct net_device_ops xfrmi_netdev_ops;



#define XFRMI_HASH_BITS	8

#define XFRMI_HASH_SIZE	BIT(XFRMI_HASH_BITS)



struct xfrmi_net {

	/* lists for storing interfaces in use */

	struct xfrm_if __rcu *xfrmi[1];

	struct xfrm_if __rcu *xfrmi[XFRMI_HASH_SIZE];

};



#define for_each_xfrmi_rcu(start, xi) \

	for (xi = rcu_dereference(start); xi; xi = rcu_dereference(xi->next))



static u32 xfrmi_hash(u32 if_id)

{

	return hash_32(if_id, XFRMI_HASH_BITS);

}



static struct xfrm_if *xfrmi_lookup(struct net *net, struct xfrm_state *x)

{

	struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id);

	struct xfrm_if *xi;



	for_each_xfrmi_rcu(xfrmn->xfrmi[0], xi) {

	for_each_xfrmi_rcu(xfrmn->xfrmi[xfrmi_hash(x->if_id)], xi) {

		if (x->if_id == xi->p.if_id &&

		    (xi->dev->flags & IFF_UP))

			return xi;
@@ -107,7 +115,7 @@ static struct xfrm_if *xfrmi_decode_session(struct sk_buff *skb, 


static void xfrmi_link(struct xfrmi_net *xfrmn, struct xfrm_if *xi)

{

	struct xfrm_if __rcu **xip = &xfrmn->xfrmi[0];

	struct xfrm_if __rcu **xip = &xfrmn->xfrmi[xfrmi_hash(xi->p.if_id)];



	rcu_assign_pointer(xi->next , rtnl_dereference(*xip));

	rcu_assign_pointer(*xip, xi);
@@ -118,7 +126,7 @@ static void xfrmi_unlink(struct xfrmi_net *xfrmn, struct xfrm_if *xi) 
	struct xfrm_if __rcu **xip;

	struct xfrm_if *iter;



	for (xip = &xfrmn->xfrmi[0];

	for (xip = &xfrmn->xfrmi[xfrmi_hash(xi->p.if_id)];

	     (iter = rtnl_dereference(*xip)) != NULL;

	     xip = &iter->next) {

		if (xi == iter) {
@@ -162,7 +170,7 @@ static struct xfrm_if *xfrmi_locate(struct net *net, struct xfrm_if_parms *p) 
	struct xfrm_if *xi;

	struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id);



	for (xip = &xfrmn->xfrmi[0];

	for (xip = &xfrmn->xfrmi[xfrmi_hash(p->if_id)];

	     (xi = rtnl_dereference(*xip)) != NULL;

	     xip = &xi->next)

		if (xi->p.if_id == p->if_id)
@@ -761,12 +769,15 @@ static void __net_exit xfrmi_exit_batch_net(struct list_head *net_exit_list) 
		struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id);

		struct xfrm_if __rcu **xip;

		struct xfrm_if *xi;

		int i;



		for (xip = &xfrmn->xfrmi[0];

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

			for (xip = &xfrmn->xfrmi[i];

			     (xi = rtnl_dereference(*xip)) != NULL;

			     xip = &xi->next)

				unregister_netdevice_queue(xi->dev, &list);

		}

	}

	unregister_netdevice_many(&list);

	rtnl_unlock();

}