memcg: enable accounting for posix_timers_cache slab

A program may create multiple interval timers using timer_create().  For
each timer the kernel preallocates a "queued real-time signal",
Consequently, the number of timers is limited by the RLIMIT_SIGPENDING
resource limit.  The allocated object is quite small, ~250 bytes, but even
the default signal limits allow to consume up to 100 megabytes per user.

It makes sense to account for them to limit the host's memory consumption
from inside the memcg-limited container.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Vasily Averin <[email protected]>
Reviewed-by: Thomas Gleixner <[email protected]>
Reviewed-by: Shakeel Butt <[email protected]>
Cc: Alexander Viro <[email protected]>
Cc: Alexey Dobriyan <[email protected]>
Cc: Andrei Vagin <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Christian Brauner <[email protected]>
Cc: Dmitry Safonov <[email protected]>
Cc: "Eric W. Biederman" <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: "J. Bruce Fields" <[email protected]>
Cc: Jeff Layton <[email protected]>
Cc: Jens Axboe <[email protected]>
Cc: Jiri Slaby <[email protected]>
Cc: Johannes Weiner <[email protected]>
Cc: Kirill Tkhai <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: Roman Gushchin <[email protected]>
Cc: Serge Hallyn <[email protected]>
Cc: Tejun Heo <[email protected]>
Cc: Vladimir Davydov <[email protected]>
Cc: Yutian Yang <[email protected]>
Cc: Zefan Li <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

1 files changed, 2 insertions, 2 deletions

diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index dd5697d7347b..7363f81dc31a 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -273,8 +273,8 @@ static int posix_get_hrtimer_res(clockid_t which_clock, struct timespec64 *tp)
 static __init int init_posix_timers(void)
 {
 	posix_timers_cache = kmem_cache_create("posix_timers_cache",
-					sizeof (struct k_itimer), 0, SLAB_PANIC,
-					NULL);
+					sizeof(struct k_itimer), 0,
+					SLAB_PANIC | SLAB_ACCOUNT, NULL);
 	return 0;
 }
 __initcall(init_posix_timers);