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Date:   Tue, 15 Sep 2020 12:18:14 -0400
From:   Peter Xu <peterx@redhat.com>
To:     Oleg Nesterov <oleg@redhat.com>
Cc:     linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        "Maya B . Gokhale" <gokhale2@llnl.gov>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Yang Shi <yang.shi@linux.alibaba.com>,
        Marty Mcfadden <mcfadden8@llnl.gov>,
        Kirill Shutemov <kirill@shutemov.name>,
        Jann Horn <jannh@google.com>, Jan Kara <jack@suse.cz>,
        Kirill Tkhai <ktkhai@virtuozzo.com>,
        Andrea Arcangeli <aarcange@redhat.com>,
        Christoph Hellwig <hch@lst.de>,
        Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH 1/4] mm: Trial do_wp_page() simplification
Message-ID: <20200915161814.GC2949@xz-x1>
References: <20200821234958.7896-1-peterx@redhat.com>
 <20200821234958.7896-2-peterx@redhat.com>
 <20200915150349.GA22415@redhat.com>
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On Tue, Sep 15, 2020 at 05:03:49PM +0200, Oleg Nesterov wrote:
> > -		if (reuse_swap_page(vmf->page, &total_map_swapcount)) {
> 
> It seems that nobody else calls reuse_swap_page() with total_map_swapcount != NULL.

Seems correct.  Though maybe we could postpone the cleanup later, until the
fallouts of the cow rework settle (just in case we'd like to bring some
mapcount logic back).  Thanks,

-- 
Peter Xu