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Date:   Mon, 25 Jan 2021 19:31:05 +0100
From:   Michal Hocko <mhocko@suse.com>
To:     Waiman Long <longman@redhat.com>
Cc:     Matthew Wilcox <willy@infradead.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Alex Shi <alex.shi@linux.alibaba.com>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm/filemap: Adding missing mem_cgroup_uncharge() to
 __add_to_page_cache_locked()
Message-ID: <20210125183105.GW827@dhcp22.suse.cz>
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On Mon 25-01-21 13:23:58, Waiman Long wrote:
> On 1/25/21 1:14 PM, Michal Hocko wrote:
[...]
> > With the proposed simplification by Willy
> > Acked-by: Michal Hocko <mhocko@suse.com>
> 
> Thank for the ack. However, I am a bit confused about what you mean by
> simplification. There is another linux-next patch that changes the condition
> for mem_cgroup_charge() to

This is obviously a fix and I believe should go in the next rc while
secretmem is a new feature which should wait at least to the next merge
window.

> -?????? if (!huge) {
> +?????? if (!huge && !page_is_secretmem(page)) {
> ??????????????? error = mem_cgroup_charge(page, current->mm, gfp);
> 
> That is the main reason why I introduced the boolean variable as I don't
> want to call the external page_is_secretmem() function twice.
> 
> Cheers,
> Longman
> 

-- 
Michal Hocko
SUSE Labs