Commit 77ef013a authored by David Ahern's avatar David Ahern Committed by David S. Miller
Browse files

net: mpls: Convert number of nexthops to u8 



Number of nexthops and number of alive nexthops are tracked using an
unsigned int. A route should never have more than 255 nexthops so
convert both to u8. Update all references and intermediate variables
to consistently use u8 as well.

Shrinks the size of mpls_route from 32 bytes to 24 bytes with a 2-byte
hole before the nexthops.

Signed-off-by: default avatarDavid Ahern <dsa@cumulusnetworks.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 39eb8cd1

net/mpls/af_mpls.c

+17 −11
Original line number Diff line number Diff line
@@ -197,10 +197,10 @@ static u32 mpls_multipath_hash(struct mpls_route *rt, struct sk_buff *skb) 
static struct mpls_nh *mpls_select_multipath(struct mpls_route *rt,

					     struct sk_buff *skb)

{

	unsigned int alive;

	u32 hash = 0;

	int nh_index = 0;

	int n = 0;

	u8 alive;



	/* No need to look further into packet if there's only

	 * one path
@@ -466,7 +466,7 @@ struct mpls_route_config { 
	int			rc_mp_len;

};



static struct mpls_route *mpls_rt_alloc(int num_nh, u8 max_alen)

static struct mpls_route *mpls_rt_alloc(u8 num_nh, u8 max_alen)

{

	u8 max_alen_aligned = ALIGN(max_alen, VIA_ALEN_ALIGN);

	struct mpls_route *rt;
@@ -744,11 +744,11 @@ errout: 
	return err;

}



static int mpls_count_nexthops(struct rtnexthop *rtnh, int len,

static u8 mpls_count_nexthops(struct rtnexthop *rtnh, int len,

			      u8 cfg_via_alen, u8 *max_via_alen)

{

	int nhs = 0;

	int remaining = len;

	u8 nhs = 0;



	if (!rtnh) {

		*max_via_alen = cfg_via_alen;
@@ -773,7 +773,13 @@ static int mpls_count_nexthops(struct rtnexthop *rtnh, int len, 
						      via_alen);

		}



		/* number of nexthops is tracked by a u8.

		 * Check for overflow.

		 */

		if (nhs == 255)

			return 0;

		nhs++;



		rtnh = rtnh_next(rtnh, &remaining);

	}
@@ -787,8 +793,8 @@ static int mpls_nh_build_multi(struct mpls_route_config *cfg, 
	struct rtnexthop *rtnh = cfg->rc_mp;

	struct nlattr *nla_via, *nla_newdst;

	int remaining = cfg->rc_mp_len;

	int nhs = 0;

	int err = 0;

	u8 nhs = 0;



	change_nexthops(rt) {

		int attrlen;
@@ -842,7 +848,7 @@ static int mpls_route_add(struct mpls_route_config *cfg) 
	int err = -EINVAL;

	u8 max_via_alen;

	unsigned index;

	int nhs;

	u8 nhs;



	index = cfg->rc_label;
@@ -1310,7 +1316,7 @@ static void mpls_ifdown(struct net_device *dev, int event) 
{

	struct mpls_route __rcu **platform_label;

	struct net *net = dev_net(dev);

	unsigned int alive, deleted;

	u8 alive, deleted;

	unsigned index;



	platform_label = rtnl_dereference(net->mpls.platform_label);
@@ -1362,7 +1368,7 @@ static void mpls_ifup(struct net_device *dev, unsigned int flags) 
	struct mpls_route __rcu **platform_label;

	struct net *net = dev_net(dev);

	unsigned index;

	int alive;

	u8 alive;



	platform_label = rtnl_dereference(net->mpls.platform_label);

	for (index = 0; index < net->mpls.platform_labels; index++) {
@@ -1786,8 +1792,8 @@ static int mpls_dump_route(struct sk_buff *skb, u32 portid, u32 seq, int event, 
	} else {

		struct rtnexthop *rtnh;

		struct nlattr *mp;

		int dead = 0;

		int linkdown = 0;

		u8 linkdown = 0;

		u8 dead = 0;



		mp = nla_nest_start(skb, RTA_MULTIPATH);

		if (!mp)

net/mpls/internal.h

+3 −2
Original line number Diff line number Diff line
@@ -127,12 +127,13 @@ struct mpls_route { /* next hop label forwarding entry */ 
	u8			rt_payload_type;

	u8			rt_max_alen;

	u8			rt_ttl_propagate;

	unsigned int		rt_nhn;

	u8			rt_nhn;



	/* rt_nhn_alive is accessed under RCU in the packet path; it

	 * is modified handling netdev events with rtnl lock held

	 */

	unsigned int		rt_nhn_alive;

	u8			rt_nhn_alive;

	u16			rt_reserved1;

	struct mpls_nh		rt_nh[0];

};

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