[PATCH v4 14/16] memcg: enable accounting for fasync_cache

From: Vasily Averin
Date: Wed Apr 28 2021 - 02:54:16 EST


fasync_struct is used by almost all character device drivers to set up
the fasync queue, and for regular files by the file lease code.
This structure is quite small but long-living and it can be assigned
for any open file.

It makes sense to account for its allocations to restrict the host's
memory consumption from inside the memcg-limited container.

Signed-off-by: Vasily Averin <vvs@xxxxxxxxxxxxx>
---
fs/fcntl.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/fcntl.c b/fs/fcntl.c
index dfc72f1..7941559 100644
--- a/fs/fcntl.c
+++ b/fs/fcntl.c
@@ -1049,7 +1049,8 @@ static int __init fcntl_init(void)
__FMODE_EXEC | __FMODE_NONOTIFY));

fasync_cache = kmem_cache_create("fasync_cache",
- sizeof(struct fasync_struct), 0, SLAB_PANIC, NULL);
+ sizeof(struct fasync_struct), 0,
+ SLAB_PANIC | SLAB_ACCOUNT, NULL);
return 0;
}

--
1.8.3.1