net: dst: remove gc leftovers

#include <net/neighbour.h>

#include <asm/processor.h>

#define DST_GC_MIN	(HZ/10)

#define DST_GC_INC	(HZ/2)

#define DST_GC_MAX	(120*HZ)

/* Each dst_entry has reference count and sits in some parent list(s).

 * When it is removed from parent list, it is "freed" (dst_free).

 * After this it enters dead state (dst->obsolete > 0) and if its refcnt

 * is zero, it can be destroyed immediately, otherwise it is added

 * to gc list and garbage collector periodically checks the refcnt.

 */

struct sk_buff;

struct dst_entry {

#include <net/dst.h>

#include <net/dst_metadata.h>

/*

 * Theory of operations:

 * 1) We use a list, protected by a spinlock, to add

 *    new entries from both BH and non-BH context.

 * 2) In order to keep spinlock held for a small delay,

 *    we use a second list where are stored long lived

 *    entries, that are handled by the garbage collect thread

 *    fired by a workqueue.

 * 3) This list is guarded by a mutex,

 *    so that the gc_task and dst_dev_event() can be synchronized.

 */

/*

 * We want to keep lock & list close together

 * to dirty as few cache lines as possible in __dst_free().

 * As this is not a very strong hint, we dont force an alignment on SMP.

 */

int dst_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb)

{

	kfree_skb(skb);

	 *

	 * When a PMTU/redirect information update invalidates a route,

	 * this is indicated by setting obsolete to DST_OBSOLETE_KILL or

	 * DST_OBSOLETE_DEAD by dst_free().

	 * DST_OBSOLETE_DEAD.

	 */

	if (dst->obsolete != DST_OBSOLETE_FORCE_CHK || rt_is_expired(rt))

		return NULL;