From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: [PATCH] tunnels: add __rcu annotations Date: Tue, 26 Oct 2010 09:01:26 +0200 Message-ID: <1288076486.3296.85.camel@edumazet-laptop> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: netdev To: David Miller Return-path: Received: from mail-wy0-f174.google.com ([74.125.82.174]:63715 "EHLO mail-wy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755914Ab0JZHBe (ORCPT ); Tue, 26 Oct 2010 03:01:34 -0400 Received: by wyf28 with SMTP id 28so4262324wyf.19 for ; Tue, 26 Oct 2010 00:01:32 -0700 (PDT) Sender: netdev-owner@vger.kernel.org List-ID: Add __rcu annotations to : (struct ip_tunnel)->prl (struct ip_tunnel_prl_entry)->next (struct xfrm_tunnel)->next struct xfrm_tunnel *tunnel4_handlers struct xfrm_tunnel *tunnel64_handlers And use appropriate rcu primitives to reduce sparse warnings if CONFIG_SPARSE_RCU_POINTER=y Signed-off-by: Eric Dumazet --- include/net/ipip.h | 4 ++-- include/net/xfrm.h | 2 +- net/ipv4/tunnel4.c | 29 +++++++++++++++++++---------- 3 files changed, 22 insertions(+), 13 deletions(-) diff --git a/include/net/ipip.h b/include/net/ipip.h index 0403fe4..a32654d 100644 --- a/include/net/ipip.h +++ b/include/net/ipip.h @@ -34,12 +34,12 @@ struct ip_tunnel { #ifdef CONFIG_IPV6_SIT_6RD struct ip_tunnel_6rd_parm ip6rd; #endif - struct ip_tunnel_prl_entry *prl; /* potential router list */ + struct ip_tunnel_prl_entry __rcu *prl; /* potential router list */ unsigned int prl_count; /* # of entries in PRL */ }; struct ip_tunnel_prl_entry { - struct ip_tunnel_prl_entry *next; + struct ip_tunnel_prl_entry __rcu *next; __be32 addr; u16 flags; struct rcu_head rcu_head; diff --git a/include/net/xfrm.h b/include/net/xfrm.h index ffcd478..bcfb6b2 100644 --- a/include/net/xfrm.h +++ b/include/net/xfrm.h @@ -1264,7 +1264,7 @@ struct xfrm_tunnel { int (*handler)(struct sk_buff *skb); int (*err_handler)(struct sk_buff *skb, u32 info); - struct xfrm_tunnel *next; + struct xfrm_tunnel __rcu *next; int priority; }; diff --git a/net/ipv4/tunnel4.c b/net/ipv4/tunnel4.c index 9a17bd2..ac3b3ee 100644 --- a/net/ipv4/tunnel4.c +++ b/net/ipv4/tunnel4.c @@ -14,27 +14,32 @@ #include #include -static struct xfrm_tunnel *tunnel4_handlers __read_mostly; -static struct xfrm_tunnel *tunnel64_handlers __read_mostly; +static struct xfrm_tunnel __rcu *tunnel4_handlers __read_mostly; +static struct xfrm_tunnel __rcu *tunnel64_handlers __read_mostly; static DEFINE_MUTEX(tunnel4_mutex); -static inline struct xfrm_tunnel **fam_handlers(unsigned short family) +static inline struct xfrm_tunnel __rcu **fam_handlers(unsigned short family) { return (family == AF_INET) ? &tunnel4_handlers : &tunnel64_handlers; } int xfrm4_tunnel_register(struct xfrm_tunnel *handler, unsigned short family) { - struct xfrm_tunnel **pprev; + struct xfrm_tunnel __rcu **pprev; + struct xfrm_tunnel *t; + int ret = -EEXIST; int priority = handler->priority; mutex_lock(&tunnel4_mutex); - for (pprev = fam_handlers(family); *pprev; pprev = &(*pprev)->next) { - if ((*pprev)->priority > priority) + for (pprev = fam_handlers(family); + (t = rcu_dereference_protected(*pprev, + lockdep_is_held(&tunnel4_mutex))) != NULL; + pprev = &t->next) { + if (t->priority > priority) break; - if ((*pprev)->priority == priority) + if (t->priority == priority) goto err; } @@ -52,13 +57,17 @@ EXPORT_SYMBOL(xfrm4_tunnel_register); int xfrm4_tunnel_deregister(struct xfrm_tunnel *handler, unsigned short family) { - struct xfrm_tunnel **pprev; + struct xfrm_tunnel __rcu **pprev; + struct xfrm_tunnel *t; int ret = -ENOENT; mutex_lock(&tunnel4_mutex); - for (pprev = fam_handlers(family); *pprev; pprev = &(*pprev)->next) { - if (*pprev == handler) { + for (pprev = fam_handlers(family); + (t = rcu_dereference_protected(*pprev, + lockdep_is_held(&tunnel4_mutex))) != NULL; + pprev = &t->next) { + if (t == handler) { *pprev = handler->next; ret = 0; break;