memcg: enable accounting for inet_bin_bucket cache

net namespace can create up to 64K tcp and dccp ports and force kernel
to allocate up to several megabytes of memory per netns
for inet_bind_bucket objects.

It makes sense to account for them to restrict the host's memory
consumption from inside the memcg-limited container.
Signed-off-by: NVasily Averin <vvs@virtuozzo.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/dccp/proto.c

@@ -1126,7 +1126,7 @@ static int __init dccp_init(void)
 	dccp_hashinfo.bind_bucket_cachep =
 		kmem_cache_create("dccp_bind_bucket",
 				  sizeof(struct inet_bind_bucket), 0,
-				  SLAB_HWCACHE_ALIGN, NULL);
+				  SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT, NULL);
 	if (!dccp_hashinfo.bind_bucket_cachep)
 		goto out_free_hashinfo2;
 

net/ipv4/tcp.c

@@ -4512,7 +4512,9 @@ void __init tcp_init(void)
 	tcp_hashinfo.bind_bucket_cachep =
 		kmem_cache_create("tcp_bind_bucket",
 				  sizeof(struct inet_bind_bucket), 0,
-				  SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
+				  SLAB_HWCACHE_ALIGN | SLAB_PANIC |
+				  SLAB_ACCOUNT,
+				  NULL);
 
 	/* Size and allocate the main established and bind bucket
 	 * hash tables.