Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754010AbdFGXHy (ORCPT ); Wed, 7 Jun 2017 19:07:54 -0400 Received: from wtarreau.pck.nerim.net ([62.212.114.60]:50955 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752965AbdFGXHv (ORCPT ); Wed, 7 Jun 2017 19:07:51 -0400 From: Willy Tarreau To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, linux@roeck-us.net Cc: Li RongQing , Stephen Hemminger , Eric Dumazet , "David S . Miller" , Willy Tarreau Subject: [PATCH 3.10 238/250] ipv6: fix the use of pcpu_tstats in ip6_tunnel Date: Thu, 8 Jun 2017 01:00:24 +0200 Message-Id: <1496876436-32402-239-git-send-email-w@1wt.eu> X-Mailer: git-send-email 2.8.0.rc2.1.gbe9624a In-Reply-To: <1496876436-32402-1-git-send-email-w@1wt.eu> References: <1496876436-32402-1-git-send-email-w@1wt.eu> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2031 Lines: 65 From: Li RongQing commit abb6013cca147ad940b0e9fee260d2d9e93b7018 upstream. 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 Signed-off-by: Willy Tarreau --- 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 61a8995..efc77ac 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; @@ -832,8 +841,10 @@ 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); -- 2.8.0.rc2.1.gbe9624a