Commit 910a71ed authored by Steffen Klassert's avatar Steffen Klassert
Browse files

Merge remote-tracking branch 'origin/testing'



Eyal Birger says:

====================
When having many xfrm interfaces, the linear lookup of devices based on
if_id becomes costly.

The first patch refactors xfrmi_decode_session() to use the xi used in
the netdevice priv context instead of looking it up in the list based
on ifindex. This is needed in order to use if_id as the only key used
for xi lookup.

The second patch extends the existing infrastructure - which already
stores the xfrmi contexts in an array of lists - to use a hash of the
if_id.

Example benchmarks:
- running on a KVM based VM
- xfrm tunnel mode between two namespaces
- xfrm interface in one namespace (10.0.0.2)

Before this change set:

Single xfrm interface in namespace:
$ netperf -H 10.0.0.2 -l8 -I95,10 -t TCP_STREAM

MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 10.0.0.2 () port 0 AF_INET : +/-5.000% @ 95% conf.  : demo
Recv   Send    Send
Socket Socket  Message  Elapsed
Size   Size    Size     Time     Throughput
bytes  bytes   bytes    secs.    10^6bits/sec

131072  16384  16384    8.00      298.36

After adding 400 xfrmi interfaces in the same namespace:

$ netperf -H 10.0.0.2 -l8 -I95,10 -t TCP_STREAM

MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 10.0.0.2 () port 0 AF_INET : +/-5.000% @ 95% conf.  : demo
Recv   Send    Send
Socket Socket  Message  Elapsed
Size   Size    Size     Time     Throughput
bytes  bytes   bytes    secs.    10^6bits/sec

131072  16384  16384    8.00      221.77

After this patchset there was no observed change after adding the
xfrmi interfaces.
====================

Signed-off-by: default avatarSteffen Klassert <steffen.klassert@secunet.com>
parents 2d4c7986 e98e4456
Loading
Loading
Loading
Loading
+33 −19
Original line number Diff line number Diff line
@@ -47,21 +47,30 @@ static int xfrmi_dev_init(struct net_device *dev);
static void xfrmi_dev_setup(struct net_device *dev);
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;
@@ -73,8 +82,7 @@ static struct xfrm_if *xfrmi_lookup(struct net *net, struct xfrm_state *x)
static struct xfrm_if *xfrmi_decode_session(struct sk_buff *skb,
					    unsigned short family)
{
	struct xfrmi_net *xfrmn;
	struct xfrm_if *xi;
	struct net_device *dev;
	int ifindex = 0;

	if (!secpath_exists(skb) || !skb->dev)
@@ -88,23 +96,26 @@ static struct xfrm_if *xfrmi_decode_session(struct sk_buff *skb,
		ifindex = inet_sdif(skb);
		break;
	}
	if (!ifindex)
		ifindex = skb->dev->ifindex;

	xfrmn = net_generic(xs_net(xfrm_input_state(skb)), xfrmi_net_id);
	if (ifindex) {
		struct net *net = xs_net(xfrm_input_state(skb));

	for_each_xfrmi_rcu(xfrmn->xfrmi[0], xi) {
		if (ifindex == xi->dev->ifindex &&
			(xi->dev->flags & IFF_UP))
				return xi;
		dev = dev_get_by_index_rcu(net, ifindex);
	} else {
		dev = skb->dev;
	}

	if (!dev || !(dev->flags & IFF_UP))
		return NULL;
	if (dev->netdev_ops != &xfrmi_netdev_ops)
		return NULL;

	return netdev_priv(dev);
}

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);
@@ -115,7 +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) {
@@ -159,7 +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)
@@ -758,12 +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();
}