Re: [PATCH] memcg: cleanup root memcg checks
From: Michal Hocko
Date: Wed Feb 24 2021 - 04:32:24 EST
On Tue 23-02-21 12:56:25, Shakeel Butt wrote:
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Replace the implicit checking of root memcg with explicit root memcg
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checking i.e. !css->parent with mem_cgroup_is_root().
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Signed-off-by: Shakeel Butt <shakeelb@xxxxxxxxxx>
Acked-by: Michal Hocko <mhocko@xxxxxxxx>
Thanks!
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---
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mm/memcontrol.c | 4 ++--
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1 file changed, 2 insertions(+), 2 deletions(-)
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diff --git a/mm/memcontrol.c b/mm/memcontrol.c
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index dcb5665aeb69..79046ad3eec0 100644
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--- a/mm/memcontrol.c
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+++ b/mm/memcontrol.c
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@@ -4141,7 +4141,7 @@ static int mem_cgroup_swappiness_write(struct cgroup_subsys_state *css,
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if (val > 100)
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return -EINVAL;
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- if (css->parent)
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+ if (!mem_cgroup_is_root(memcg))
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memcg->swappiness = val;
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else
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vm_swappiness = val;
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@@ -4491,7 +4491,7 @@ static int mem_cgroup_oom_control_write(struct cgroup_subsys_state *css,
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struct mem_cgroup *memcg = mem_cgroup_from_css(css);
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/* cannot set to root cgroup and only 0 and 1 are allowed */
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- if (!css->parent || !((val == 0) || (val == 1)))
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+ if (mem_cgroup_is_root(memcg) || !((val == 0) || (val == 1)))
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return -EINVAL;
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memcg->oom_kill_disable = val;
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--
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2.30.0.617.g56c4b15f3c-goog
--
Michal Hocko
SUSE Labs