fib_trie: no need to delay vfree()

Now that vfree() can be called from interrupt contexts, there's no
need to play games with schedule_work() to escape calling vfree()
from RCU callbacks.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv4/fib_trie.c

@@ -125,7 +125,6 @@ struct tnode {
 	unsigned int empty_children;	/* KEYLENGTH bits needed */
 	union {
 		struct rcu_head rcu;
-		struct work_struct work;
 		struct tnode *tnode_free;
 	};
 	struct rt_trie_node __rcu *child[0];
@@ -383,12 +382,6 @@ static struct tnode *tnode_alloc(size_t size)
 		return vzalloc(size);
 }
 
-static void __tnode_vfree(struct work_struct *arg)
-{
-	struct tnode *tn = container_of(arg, struct tnode, work);
-	vfree(tn);
-}
-
 static void __tnode_free_rcu(struct rcu_head *head)
 {
 	struct tnode *tn = container_of(head, struct tnode, rcu);
@@ -397,10 +390,8 @@ static void __tnode_free_rcu(struct rcu_head *head)
 
 	if (size <= PAGE_SIZE)
 		kfree(tn);
-	else {
-		INIT_WORK(&tn->work, __tnode_vfree);
-		schedule_work(&tn->work);
-	}
+	else
+		vfree(tn);
 }
 
 static inline void tnode_free(struct tnode *tn)