From abb6013cca147ad940b0e9fee260d2d9e93b7018 Mon Sep 17 00:00:00 2001 From: Li RongQing Date: Thu, 2 Jan 2014 13:20:12 +0800 Subject: [PATCH] ipv6: fix the use of pcpu_tstats in ip6_tunnel when read/write the 64bit data, the correct lock should be hold. Fixes: 87b6d218f3adb ("tunnel: implement 64 bits statistics") Cc: Stephen Hemminger Cc: Eric Dumazet Signed-off-by: Li RongQing Signed-off-by: David S. Miller --- net/ipv6/ip6_tunnel.c | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-) diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c index d6062325db08..7881965a8248 100644 --- a/net/ipv6/ip6_tunnel.c +++ b/net/ipv6/ip6_tunnel.c @@ -103,16 +103,25 @@ struct ip6_tnl_net { static struct net_device_stats *ip6_get_stats(struct net_device *dev) { - struct pcpu_tstats sum = { 0 }; + struct pcpu_tstats tmp, sum = { 0 }; int i; for_each_possible_cpu(i) { + unsigned int start; const struct pcpu_tstats *tstats = per_cpu_ptr(dev->tstats, i); - sum.rx_packets += tstats->rx_packets; - sum.rx_bytes += tstats->rx_bytes; - sum.tx_packets += tstats->tx_packets; - sum.tx_bytes += tstats->tx_bytes; + do { + start = u64_stats_fetch_begin_bh(&tstats->syncp); + tmp.rx_packets = tstats->rx_packets; + tmp.rx_bytes = tstats->rx_bytes; + tmp.tx_packets = tstats->tx_packets; + tmp.tx_bytes = tstats->tx_bytes; + } while (u64_stats_fetch_retry_bh(&tstats->syncp, start)); + + sum.rx_packets += tmp.rx_packets; + sum.rx_bytes += tmp.rx_bytes; + sum.tx_packets += tmp.tx_packets; + sum.tx_bytes += tmp.tx_bytes; } dev->stats.rx_packets = sum.rx_packets; dev->stats.rx_bytes = sum.rx_bytes; @@ -824,8 +833,10 @@ static int ip6_tnl_rcv(struct sk_buff *skb, __u16 protocol, } tstats = this_cpu_ptr(t->dev->tstats); + u64_stats_update_begin(&tstats->syncp); tstats->rx_packets++; tstats->rx_bytes += skb->len; + u64_stats_update_end(&tstats->syncp); netif_rx(skb); -- 2.34.1