Re: [PATCH] memcg: cleanup root memcg checks

2021-02-24 Thread Johannes Weiner
On Tue, Feb 23, 2021 at 12:56:25PM -0800, Shakeel Butt wrote:
> Replace the implicit checking of root memcg with explicit root memcg
> checking i.e. !css->parent with mem_cgroup_is_root().
> 
> Signed-off-by: Shakeel Butt 

Acked-by: Johannes Weiner 


Re: [PATCH] memcg: cleanup root memcg checks

2021-02-24 Thread Michal Hocko
On Tue 23-02-21 12:56:25, Shakeel Butt wrote:
> Replace the implicit checking of root memcg with explicit root memcg
> checking i.e. !css->parent with mem_cgroup_is_root().
>
> Signed-off-by: Shakeel Butt 

Acked-by: Michal Hocko 

Thanks!

> ---
>  mm/memcontrol.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index dcb5665aeb69..79046ad3eec0 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -4141,7 +4141,7 @@ static int mem_cgroup_swappiness_write(struct 
> cgroup_subsys_state *css,
>   if (val > 100)
>   return -EINVAL;
>  
> - if (css->parent)
> + if (!mem_cgroup_is_root(memcg))
>   memcg->swappiness = val;
>   else
>   vm_swappiness = val;
> @@ -4491,7 +4491,7 @@ static int mem_cgroup_oom_control_write(struct 
> cgroup_subsys_state *css,
>   struct mem_cgroup *memcg = mem_cgroup_from_css(css);
>  
>   /* cannot set to root cgroup and only 0 and 1 are allowed */
> - if (!css->parent || !((val == 0) || (val == 1)))
> + if (mem_cgroup_is_root(memcg) || !((val == 0) || (val == 1)))
>   return -EINVAL;
>  
>   memcg->oom_kill_disable = val;
> -- 
> 2.30.0.617.g56c4b15f3c-goog

-- 
Michal Hocko
SUSE Labs


[PATCH] memcg: cleanup root memcg checks

2021-02-23 Thread Shakeel Butt
Replace the implicit checking of root memcg with explicit root memcg
checking i.e. !css->parent with mem_cgroup_is_root().

Signed-off-by: Shakeel Butt 
---
 mm/memcontrol.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index dcb5665aeb69..79046ad3eec0 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -4141,7 +4141,7 @@ static int mem_cgroup_swappiness_write(struct 
cgroup_subsys_state *css,
if (val > 100)
return -EINVAL;
 
-   if (css->parent)
+   if (!mem_cgroup_is_root(memcg))
memcg->swappiness = val;
else
vm_swappiness = val;
@@ -4491,7 +4491,7 @@ static int mem_cgroup_oom_control_write(struct 
cgroup_subsys_state *css,
struct mem_cgroup *memcg = mem_cgroup_from_css(css);
 
/* cannot set to root cgroup and only 0 and 1 are allowed */
-   if (!css->parent || !((val == 0) || (val == 1)))
+   if (mem_cgroup_is_root(memcg) || !((val == 0) || (val == 1)))
return -EINVAL;
 
memcg->oom_kill_disable = val;
-- 
2.30.0.617.g56c4b15f3c-goog