Re: [PATCH] memcg: accounting for objects allocated for new netdevice

Michal Koutný
2022-04-27T14:01:53Z

Hello Vasily.

On Wed, Apr 27, 2022 at 01:37:50PM +0300, Vasily Averin <vvs-GEFAQzZX7r8dnm+yROfE0A@public.gmane.org> wrote:
> diff --git a/fs/kernfs/mount.c b/fs/kernfs/mount.c
> index cfa79715fc1a..2881aeeaa880 100644
> --- a/fs/kernfs/mount.c
> +++ b/fs/kernfs/mount.c
> @@ -391,7 +391,7 @@ void __init kernfs_init(void)
> {
> kernfs_node_cache = kmem_cache_create("kernfs_node_cache",
> sizeof(struct kernfs_node),
> - 0, SLAB_PANIC, NULL);
> + 0, SLAB_PANIC | SLAB_ACCOUNT, NULL);

kernfs accounting you say?
kernfs backs up also cgroups, so the parent-child accounting comes to my
mind.
See the temporary switch to parent memcg in mem_cgroup_css_alloc().

(I mean this makes some sense but I'd suggest unlumping the kernfs into
a separate path for possible discussion and its not-only-netdevice
effects.)

Thanks,
Michal