Merge tag 'v3.10.84' into update
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / packet / af_packet.c
index 1e8ff53dded4528a3c7ddcce6b56686e95699555..56f9bd24ad1a9cb8946c0928da459e420bd43438 100644 (file)
@@ -1150,16 +1150,6 @@ static void packet_sock_destruct(struct sock *sk)
        sk_refcnt_debug_dec(sk);
 }
 
-static int fanout_rr_next(struct packet_fanout *f, unsigned int num)
-{
-       int x = atomic_read(&f->rr_cur) + 1;
-
-       if (x >= num)
-               x = 0;
-
-       return x;
-}
-
 static unsigned int fanout_demux_hash(struct packet_fanout *f,
                                      struct sk_buff *skb,
                                      unsigned int num)
@@ -1171,13 +1161,9 @@ static unsigned int fanout_demux_lb(struct packet_fanout *f,
                                    struct sk_buff *skb,
                                    unsigned int num)
 {
-       int cur, old;
+       unsigned int val = atomic_inc_return(&f->rr_cur);
 
-       cur = atomic_read(&f->rr_cur);
-       while ((old = atomic_cmpxchg(&f->rr_cur, cur,
-                                    fanout_rr_next(f, num))) != cur)
-               cur = old;
-       return cur;
+       return val % num;
 }
 
 static unsigned int fanout_demux_cpu(struct packet_fanout *f,
@@ -1217,7 +1203,7 @@ static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev,
                             struct packet_type *pt, struct net_device *orig_dev)
 {
        struct packet_fanout *f = pt->af_packet_priv;
-       unsigned int num = f->num_members;
+       unsigned int num = ACCESS_ONCE(f->num_members);
        struct packet_sock *po;
        unsigned int idx;