diff options
| author | Eric Dumazet <edumazet@google.com> | 2012-10-28 22:33:23 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2012-11-03 14:59:04 -0400 |
| commit | 6da025fa23bb10c82f80de319c837ed2b02306e4 (patch) | |
| tree | 64992521a7fa74c04eff45fffc88dd56dfb10ba7 | |
| parent | b26ddd813031666293c95e84c997eb8b1f97bd38 (diff) | |
| download | linux-6da025fa23bb10c82f80de319c837ed2b02306e4.tar.gz linux-6da025fa23bb10c82f80de319c837ed2b02306e4.tar.bz2 linux-6da025fa23bb10c82f80de319c837ed2b02306e4.zip | |
ipv4: avoid a test in ip_rt_put()
We can save a test in ip_rt_put(), considering dst_release() accepts
a NULL parameter, and dst is first element in rtable.
Add a BUILD_BUG_ON() to catch any change that could break this
assertion.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Cong Wang <amwang@redhat.com>
Acked-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | include/net/route.h | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/include/net/route.h b/include/net/route.h index bc40b633a5c4..2ea40c1b5e00 100644 --- a/include/net/route.h +++ b/include/net/route.h @@ -198,10 +198,13 @@ struct in_ifaddr; extern void fib_add_ifaddr(struct in_ifaddr *); extern void fib_del_ifaddr(struct in_ifaddr *, struct in_ifaddr *); -static inline void ip_rt_put(struct rtable * rt) +static inline void ip_rt_put(struct rtable *rt) { - if (rt) - dst_release(&rt->dst); + /* dst_release() accepts a NULL parameter. + * We rely on dst being first structure in struct rtable + */ + BUILD_BUG_ON(offsetof(struct rtable, dst) != 0); + dst_release(&rt->dst); } #define IPTOS_RT_MASK (IPTOS_TOS_MASK & ~3) |