From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: Re: [PATCH] ipv6: replace write lock with read lock when get route info Date: Wed, 12 Sep 2012 09:45:07 +0200 Message-ID: <1347435907.13103.693.camel@edumazet-glaptop> References: <1347427553-17781-1-git-send-email-roy.qing.li@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org To: roy.qing.li@gmail.com Return-path: Received: from mail-ee0-f46.google.com ([74.125.83.46]:49840 "EHLO mail-ee0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751654Ab2ILHpM (ORCPT ); Wed, 12 Sep 2012 03:45:12 -0400 Received: by eekc1 with SMTP id c1so995768eek.19 for ; Wed, 12 Sep 2012 00:45:11 -0700 (PDT) In-Reply-To: <1347427553-17781-1-git-send-email-roy.qing.li@gmail.com> Sender: netdev-owner@vger.kernel.org List-ID: On Wed, 2012-09-12 at 13:25 +0800, roy.qing.li@gmail.com wrote: > From: Li RongQing > > geting route info does not write rt->rt6i_table, so replace > write lock with read lock > > Signed-off-by: Li RongQing > --- > net/ipv6/route.c | 8 ++++---- > 1 files changed, 4 insertions(+), 4 deletions(-) > > diff --git a/net/ipv6/route.c b/net/ipv6/route.c > index 399613b..8be1d86 100644 > --- a/net/ipv6/route.c > +++ b/net/ipv6/route.c > @@ -1837,7 +1837,7 @@ static struct rt6_info *rt6_get_route_info(struct net *net, > if (!table) > return NULL; > > - write_lock_bh(&table->tb6_lock); > + read_lock_bh(&table->tb6_lock); > fn = fib6_locate(&table->tb6_root, prefix ,prefixlen, NULL, 0); > if (!fn) > goto out; > @@ -1853,7 +1853,7 @@ static struct rt6_info *rt6_get_route_info(struct net *net, > break; > } > out: > - write_unlock_bh(&table->tb6_lock); > + read_unlock_bh(&table->tb6_lock); > return rt; > } > > @@ -1896,7 +1896,7 @@ struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr, struct net_dev > if (!table) > return NULL; > > - write_lock_bh(&table->tb6_lock); > + read_lock_bh(&table->tb6_lock); > for (rt = table->tb6_root.leaf; rt; rt=rt->dst.rt6_next) { > if (dev == rt->dst.dev && > ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) && > @@ -1905,7 +1905,7 @@ struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr, struct net_dev > } > if (rt) > dst_hold(&rt->dst); > - write_unlock_bh(&table->tb6_lock); > + read_unlock_bh(&table->tb6_lock); > return rt; > } > Why dont you also change addrconf_get_prefix_route() ?