From mboxrd@z Thu Jan 1 00:00:00 1970 From: Cong Wang Subject: [Patch net-next v2 1/8] ipv6: drop useless rcu_read_lock() in anycast Date: Thu, 11 Sep 2014 15:35:09 -0700 Message-ID: <1410474916-21873-2-git-send-email-xiyou.wangcong@gmail.com> References: <1410474916-21873-1-git-send-email-xiyou.wangcong@gmail.com> Cc: Hannes Frederic Sowa , Hideaki YOSHIFUJI , "David S. Miller" , Cong Wang To: netdev@vger.kernel.org Return-path: Received: from mail-pd0-f179.google.com ([209.85.192.179]:38602 "EHLO mail-pd0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752241AbaIKWfj (ORCPT ); Thu, 11 Sep 2014 18:35:39 -0400 Received: by mail-pd0-f179.google.com with SMTP id g10so15322167pdj.38 for ; Thu, 11 Sep 2014 15:35:39 -0700 (PDT) In-Reply-To: <1410474916-21873-1-git-send-email-xiyou.wangcong@gmail.com> Sender: netdev-owner@vger.kernel.org List-ID: These code is now protected by rtnl lock, rcu read lock is useless now. Signed-off-by: Cong Wang --- include/linux/netdevice.h | 4 ++-- net/core/dev.c | 14 ++++++++------ net/ipv6/anycast.c | 18 ++++++------------ 3 files changed, 16 insertions(+), 20 deletions(-) diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index ba72f6b..17e640a 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -2083,8 +2083,8 @@ void __dev_remove_pack(struct packet_type *pt); void dev_add_offload(struct packet_offload *po); void dev_remove_offload(struct packet_offload *po); -struct net_device *dev_get_by_flags_rcu(struct net *net, unsigned short flags, - unsigned short mask); +struct net_device *__dev_get_by_flags(struct net *net, unsigned short flags, + unsigned short mask); struct net_device *dev_get_by_name(struct net *net, const char *name); struct net_device *dev_get_by_name_rcu(struct net *net, const char *name); struct net_device *__dev_get_by_name(struct net *net, const char *name); diff --git a/net/core/dev.c b/net/core/dev.c index 3c6a967..2595f07 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -897,23 +897,25 @@ struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type) EXPORT_SYMBOL(dev_getfirstbyhwtype); /** - * dev_get_by_flags_rcu - find any device with given flags + * __dev_get_by_flags - find any device with given flags * @net: the applicable net namespace * @if_flags: IFF_* values * @mask: bitmask of bits in if_flags to check * * Search for any interface with the given flags. Returns NULL if a device * is not found or a pointer to the device. Must be called inside - * rcu_read_lock(), and result refcount is unchanged. + * rtnl_lock(), and result refcount is unchanged. */ -struct net_device *dev_get_by_flags_rcu(struct net *net, unsigned short if_flags, - unsigned short mask) +struct net_device *__dev_get_by_flags(struct net *net, unsigned short if_flags, + unsigned short mask) { struct net_device *dev, *ret; + ASSERT_RTNL(); + ret = NULL; - for_each_netdev_rcu(net, dev) { + for_each_netdev(net, dev) { if (((dev->flags ^ if_flags) & mask) == 0) { ret = dev; break; @@ -921,7 +923,7 @@ struct net_device *dev_get_by_flags_rcu(struct net *net, unsigned short if_flags } return ret; } -EXPORT_SYMBOL(dev_get_by_flags_rcu); +EXPORT_SYMBOL(__dev_get_by_flags); /** * dev_valid_name - check if name is okay for network device diff --git a/net/ipv6/anycast.c b/net/ipv6/anycast.c index ff2de7d..3b0429b 100644 --- a/net/ipv6/anycast.c +++ b/net/ipv6/anycast.c @@ -78,7 +78,6 @@ int ipv6_sock_ac_join(struct sock *sk, int ifindex, const struct in6_addr *addr) pac->acl_addr = *addr; rtnl_lock(); - rcu_read_lock(); if (ifindex == 0) { struct rt6_info *rt; @@ -91,11 +90,11 @@ int ipv6_sock_ac_join(struct sock *sk, int ifindex, const struct in6_addr *addr) goto error; } else { /* router, no matching interface: just pick one */ - dev = dev_get_by_flags_rcu(net, IFF_UP, - IFF_UP | IFF_LOOPBACK); + dev = __dev_get_by_flags(net, IFF_UP, + IFF_UP | IFF_LOOPBACK); } } else - dev = dev_get_by_index_rcu(net, ifindex); + dev = __dev_get_by_index(net, ifindex); if (dev == NULL) { err = -ENODEV; @@ -137,7 +136,6 @@ int ipv6_sock_ac_join(struct sock *sk, int ifindex, const struct in6_addr *addr) } error: - rcu_read_unlock(); rtnl_unlock(); if (pac) sock_kfree_s(sk, pac, sizeof(*pac)); @@ -174,11 +172,9 @@ int ipv6_sock_ac_drop(struct sock *sk, int ifindex, const struct in6_addr *addr) spin_unlock_bh(&ipv6_sk_ac_lock); rtnl_lock(); - rcu_read_lock(); - dev = dev_get_by_index_rcu(net, pac->acl_ifindex); + dev = __dev_get_by_index(net, pac->acl_ifindex); if (dev) ipv6_dev_ac_dec(dev, &pac->acl_addr); - rcu_read_unlock(); rtnl_unlock(); sock_kfree_s(sk, pac, sizeof(*pac)); @@ -203,12 +199,11 @@ void ipv6_sock_ac_close(struct sock *sk) prev_index = 0; rtnl_lock(); - rcu_read_lock(); while (pac) { struct ipv6_ac_socklist *next = pac->acl_next; if (pac->acl_ifindex != prev_index) { - dev = dev_get_by_index_rcu(net, pac->acl_ifindex); + dev = __dev_get_by_index(net, pac->acl_ifindex); prev_index = pac->acl_ifindex; } if (dev) @@ -216,7 +211,6 @@ void ipv6_sock_ac_close(struct sock *sk) sock_kfree_s(sk, pac, sizeof(*pac)); pac = next; } - rcu_read_unlock(); rtnl_unlock(); } @@ -341,7 +335,7 @@ int __ipv6_dev_ac_dec(struct inet6_dev *idev, const struct in6_addr *addr) return 0; } -/* called with rcu_read_lock() */ +/* called with rtnl_lock() */ static int ipv6_dev_ac_dec(struct net_device *dev, const struct in6_addr *addr) { struct inet6_dev *idev = __in6_dev_get(dev); -- 1.8.3.1