Re: [PATCH 06/10] cgroup: convert memcg controller to the new cftypeinterface

From: KAMEZAWA Hiroyuki
Date: Mon Mar 19 2012 - 00:28:02 EST


(2012/03/17 8:35), Tejun Heo wrote:

> Convert memcg to use the new cftype based interface. memcg is rather
> special in that
>
> * memsw_cgroup_files creation is dependent on do_swap_account.
>
> * ->populate() is abused for mem_cgroup_sockets_init().
>
> memsw_cgroup_files is converted to use CGROUP_SUBSYS_CFTYPES_COND(),
> where the condition is really_do_swap_account.
>
> ->populate() is preserved for register_kmem_files() invocation but I
> strongly urge moving the initialization to the tail of ->create(). If
> there's something which can't be done from ->create(), which isn't
> clear from the comment, please let me know.
>

Okay, then, cgroup files are created in kernel/cgroup.c and memcg just
registers entries.



> Signed-off-by: Tejun Heo <tj@xxxxxxxxxx>
> Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
> Cc: Michal Hocko <mhocko@xxxxxxx>
> Cc: Balbir Singh <bsingharora@xxxxxxxxx>
> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx>
> Cc: Glauber Costa <glommer@xxxxxxxxxxxxx>
> Cc: Hugh Dickins <hughd@xxxxxxxxxx>
> Cc: Greg Thelen <gthelen@xxxxxxxxxx>
> ---
> mm/memcontrol.c | 31 ++++++-------------------------
> net/ipv4/tcp_memcontrol.c | 8 ++++----
> 2 files changed, 10 insertions(+), 29 deletions(-)
>
> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index ae2f0a8..f2221ce 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -4665,7 +4665,9 @@ static struct cftype mem_cgroup_files[] = {
> .mode = S_IRUGO,
> },
> #endif
> + { }, /* terminate */
> };
> +CGROUP_SUBSYS_CFTYPES(mem_cgroup_subsys, mem_cgroup_files);
>
> #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
> static struct cftype memsw_cgroup_files[] = {
> @@ -4694,20 +4696,10 @@ static struct cftype memsw_cgroup_files[] = {
> .trigger = mem_cgroup_reset,
> .read_u64 = mem_cgroup_read,
> },
> + { } /* terminate */
> };
> -
> -static int register_memsw_files(struct cgroup *cont, struct cgroup_subsys *ss)
> -{
> - if (!do_swap_account)
> - return 0;
> - return cgroup_add_files(cont, ss, memsw_cgroup_files,
> - ARRAY_SIZE(memsw_cgroup_files));
> -};
> -#else
> -static int register_memsw_files(struct cgroup *cont, struct cgroup_subsys *ss)
> -{
> - return 0;
> -}
> +CGROUP_SUBSYS_CFTYPES_COND(mem_cgroup_subsys, memsw_cgroup_files,
> + really_do_swap_account);


I'm sorry but why you use really_do_swap_account instead of do_swap_account ?

Thanks,
-Kame

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/