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Date:   Thu, 4 Feb 2021 10:37:43 -0800
From:   Roman Gushchin <guro@fb.com>
To:     Muchun Song <songmuchun@bytedance.com>
CC:     <hannes@cmpxchg.org>, <mhocko@kernel.org>,
        <vdavydov.dev@gmail.com>, <akpm@linux-foundation.org>,
        <cgroups@vger.kernel.org>, <linux-mm@kvack.org>,
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Subject: Re: [PATCH v2] mm: memcontrol: replace the loop with a
 list_for_each_entry()
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On Fri, Feb 05, 2021 at 12:30:55AM +0800, Muchun Song wrote:
> The rule of list walk has gone since:
> 
>  commit a9d5adeeb4b2 ("mm/memcontrol: allow to uncharge page without using page->lru field")
> 
> So remove the strange comment and replace the loop with a
> list_for_each_entry().
> 
> There is only one caller of the uncharge_list(). So just fold it into
> mem_cgroup_uncharge_list() and remove it.
> 
> Signed-off-by: Muchun Song <songmuchun@bytedance.com>
> ---
> v2:
>  - Fold uncharge_list() to mem_cgroup_uncharge_list().
> 
>  mm/memcontrol.c | 35 ++++++++---------------------------
>  1 file changed, 8 insertions(+), 27 deletions(-)

Nice cleanup!

Acked-by: Roman Gushchin <guro@fb.com>

Thanks.