On Thu, Aug 11, 2022 at 04:19:13PM +0800, liliguang wrote:
> From: Li Liguang <liliguang@xxxxxxxxx>
>
> Kswapd will reclaim memory when memory pressure is high, the
> annonymous memory will be compressed and stored in the zpool
> if zswap is enabled. The memcg_kmem_bypass() in
> get_obj_cgroup_from_page() will bypass the kernel thread and
> cause the compressed memory not charged to its memory cgroup.
>
> Remove the memcg_kmem_bypass() and properly charge compressed
> memory to its corresponding memory cgroup.
>
> Signed-off-by: Li Liguang <liliguang@xxxxxxxxx>
> ---
> mm/memcontrol.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index b69979c9ced5..6a95ea7c5ee7 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -2971,7 +2971,7 @@ struct obj_cgroup *get_obj_cgroup_from_page(struct page *page)
> {
> struct obj_cgroup *objcg;
>
> - if (!memcg_kmem_enabled() || memcg_kmem_bypass())
> + if (!memcg_kmem_enabled())
> return NULL;
>
> if (PageMemcgKmem(page)) {
> --
> 2.32.0 (Apple Git-132)
>
Hi Li!
The fix looks good to me! As we get objcg pointer from a page and not from
the current task, memcg_kmem_bypass() doesn't makes much sense.
Acked-by: Roman Gushchin <roman.gushchin@xxxxxxxxx>
Probably, we need to add
Fixes: f4840ccfca25 ("zswap: memcg accounting")
Thank you!
