inetpeer: restore small inet_peer structures
Addition of rcu_head to struct inet_peer added 16bytes on 64bit arches.
Thats a bit unfortunate, since old size was exactly 64 bytes.
This can be solved, using an union between this rcu_head an four fields,
that are normally used only when a refcount is taken on inet_peer.
rcu_head is used only when refcnt=-1, right before structure freeing.
Add a inet_peer_refcheck() function to check this assertion for a while.
We can bring back SLAB_HWCACHE_ALIGN qualifier in kmem cache creation.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 7f9515c..2e41e6f 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -204,10 +204,12 @@
* TIME-WAIT * and initialize rx_opt.ts_recent from it,
* when trying new connection.
*/
- if (peer != NULL &&
- (u32)get_seconds() - peer->tcp_ts_stamp <= TCP_PAWS_MSL) {
- tp->rx_opt.ts_recent_stamp = peer->tcp_ts_stamp;
- tp->rx_opt.ts_recent = peer->tcp_ts;
+ if (peer) {
+ inet_peer_refcheck(peer);
+ if ((u32)get_seconds() - peer->tcp_ts_stamp <= TCP_PAWS_MSL) {
+ tp->rx_opt.ts_recent_stamp = peer->tcp_ts_stamp;
+ tp->rx_opt.ts_recent = peer->tcp_ts;
+ }
}
}
@@ -1351,6 +1353,7 @@
(dst = inet_csk_route_req(sk, req)) != NULL &&
(peer = rt_get_peer((struct rtable *)dst)) != NULL &&
peer->v4daddr == saddr) {
+ inet_peer_refcheck(peer);
if ((u32)get_seconds() - peer->tcp_ts_stamp < TCP_PAWS_MSL &&
(s32)(peer->tcp_ts - req->ts_recent) >
TCP_PAWS_WINDOW) {