udp: add a counter into udp_hslot
Adds a counter in udp_hslot to keep an accurate count
of sockets present in chain.
This will permit to upcoming UDP lookup algo to chose
the shortest chain when secondary hash is added.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/udp.h b/include/net/udp.h
index 22aa2e7..9167281 100644
--- a/include/net/udp.h
+++ b/include/net/udp.h
@@ -50,8 +50,16 @@
};
#define UDP_SKB_CB(__skb) ((struct udp_skb_cb *)((__skb)->cb))
+/**
+ * struct udp_hslot - UDP hash slot
+ *
+ * @head: head of list of sockets
+ * @count: number of sockets in 'head' list
+ * @lock: spinlock protecting changes to head/count
+ */
struct udp_hslot {
struct hlist_nulls_head head;
+ int count;
spinlock_t lock;
} __attribute__((aligned(2 * sizeof(long))));