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Date:   Fri, 30 Jul 2021 08:51:27 +0200
From:   Michal Hocko <mhocko@suse.com>
To:     Miaohe Lin <linmiaohe@huawei.com>
Cc:     hannes@cmpxchg.org, vdavydov.dev@gmail.com,
        akpm@linux-foundation.org, shakeelb@google.com, guro@fb.com,
        willy@infradead.org, alexs@kernel.org, richard.weiyang@gmail.com,
        songmuchun@bytedance.com, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, cgroups@vger.kernel.org
Subject: Re: [PATCH 3/5] mm, memcg: save some atomic ops when flush is
 already true
Message-ID: <YQOhbwhJWuk5NOro@dhcp22.suse.cz>
References: <20210729125755.16871-1-linmiaohe@huawei.com>
 <20210729125755.16871-4-linmiaohe@huawei.com>
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On Thu 29-07-21 20:57:53, Miaohe Lin wrote:
> Add 'else' to save some atomic ops in obj_stock_flush_required() when
> flush is already true. No functional change intended here.
> 
> Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>

Acked-by: Michal Hocko <mhocko@suse.com>

> ---
>  mm/memcontrol.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index a03e24e57cd9..5b4592d1e0f2 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -2231,7 +2231,7 @@ static void drain_all_stock(struct mem_cgroup *root_memcg)
>  		if (memcg && stock->nr_pages &&
>  		    mem_cgroup_is_descendant(memcg, root_memcg))
>  			flush = true;
> -		if (obj_stock_flush_required(stock, root_memcg))
> +		else if (obj_stock_flush_required(stock, root_memcg))
>  			flush = true;
>  		rcu_read_unlock();
>  
> -- 
> 2.23.0

-- 
Michal Hocko
SUSE Labs