Re: [RFC PATCH 0/2] zram: objects charge to mem_cgroup

From: Michal Hocko
Date: Fri Jul 07 2023 - 03:57:16 EST


On Fri 07-07-23 12:46:13, Zhongkun He wrote:
> This is a new solution to charge ZRAM objects,more simple than
> previous one[1],The compressed RAM is currently charged to
> kernel,not to any memory cgroup.
>
> As we know, zram can be used in two ways, direct and
> indirect, this patchset can charge memory in both cases.
> Direct zram usage by process within a cgroup will fail
> to charge if there is no memory. Indirect zram usage by
> process within a cgroup via swap in PF_MEMALLOC context,
> will charge successfully.

Please state the objective you are trying to achieve by this patchset.
It is always good to summarize the previous discussion and mention what
is done differently or how previous review feedback has been addressed
but the overall idea/purpose should be always explicit.

Please elaborate more about both.

> [1]
> https://lore.kernel.org/all/20230615034830.1361853-1-hezhongkun.hzk@xxxxxxxxxxxxx/
>
> Zhongkun He (2):
> memcg: Add support for zram object charge
> zram: charge the compressed RAM to the page's memcgroup
>
> drivers/block/zram/zram_drv.c | 43 +++++++++++++++++++++++++++++++++++
> drivers/block/zram/zram_drv.h | 1 +
> include/linux/memcontrol.h | 10 ++++++++
> mm/memcontrol.c | 23 +++++++++++++++++++
> 4 files changed, 77 insertions(+)
>
> --
> 2.25.1

--
Michal Hocko
SUSE Labs