[PATCH v6 03/16] memcg: enable accounting for inet_bin_bucket cache

From: Vasily Averin
Date: Mon Jul 26 2021 - 15:00:31 EST


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: Vasily Averin <vvs@xxxxxxxxxxxxx>
---
net/dccp/proto.c | 2 +-
net/ipv4/tcp.c | 4 +++-
2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/net/dccp/proto.c b/net/dccp/proto.c
index 7eb0fb2..abb5c59 100644
--- a/net/dccp/proto.c
+++ b/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;

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index d5ab5f2..5c0605e 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -4509,7 +4509,9 @@ 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.
--
1.8.3.1