From e5b4376074e02b783e56a8f7c42d544e18112c4e Mon Sep 17 00:00:00 2001 From: Robert Olsson Date: Thu, 25 Aug 2005 13:01:03 -0700 Subject: [IPV4]: Prepare FIB core for RCU. * RCU versions of hlist_***_rcu * fib_alias partial rcu port just whats needed now. Signed-off-by: Robert Olsson Signed-off-by: Stephen Hemminger Signed-off-by: David S. Miller --- include/linux/list.h | 21 +++++++++++++++++++++ net/ipv4/fib_lookup.h | 1 + net/ipv4/fib_semantics.c | 3 ++- 3 files changed, 24 insertions(+), 1 deletion(-) diff --git a/include/linux/list.h b/include/linux/list.h index 0f2435f92db3..9b9b0eec1e8a 100644 --- a/include/linux/list.h +++ b/include/linux/list.h @@ -634,6 +634,27 @@ static inline void hlist_add_after(struct hlist_node *n, next->next->pprev = &next->next; } +static inline void hlist_add_before_rcu(struct hlist_node *n, + struct hlist_node *next) +{ + n->pprev = next->pprev; + n->next = next; + smp_wmb(); + next->pprev = &n->next; + *(n->pprev) = n; +} + +static inline void hlist_add_after_rcu(struct hlist_node *prev, + struct hlist_node *n) +{ + n->next = prev->next; + n->pprev = &prev->next; + smp_wmb(); + prev->next = n; + if (n->next) + n->next->pprev = &n->next; +} + #define hlist_entry(ptr, type, member) container_of(ptr,type,member) #define hlist_for_each(pos, head) \ diff --git a/net/ipv4/fib_lookup.h b/net/ipv4/fib_lookup.h index b729d97cfa93..ef6609ea0eb7 100644 --- a/net/ipv4/fib_lookup.h +++ b/net/ipv4/fib_lookup.h @@ -7,6 +7,7 @@ struct fib_alias { struct list_head fa_list; + struct rcu_head rcu; struct fib_info *fa_info; u8 fa_tos; u8 fa_type; diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c index 7e4651b3caa8..d41219e8037c 100644 --- a/net/ipv4/fib_semantics.c +++ b/net/ipv4/fib_semantics.c @@ -854,6 +854,7 @@ failure: return NULL; } +/* Note! fib_semantic_match intentionally uses RCU list functions. */ int fib_semantic_match(struct list_head *head, const struct flowi *flp, struct fib_result *res, __u32 zone, __u32 mask, int prefixlen) @@ -861,7 +862,7 @@ int fib_semantic_match(struct list_head *head, const struct flowi *flp, struct fib_alias *fa; int nh_sel = 0; - list_for_each_entry(fa, head, fa_list) { + list_for_each_entry_rcu(fa, head, fa_list) { int err; if (fa->fa_tos && -- cgit v1.2.1