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From:   Yu Zhao <yuzhao@google.com>
Date:   Sun, 8 Aug 2021 11:21:48 -0600
Message-ID: <CAOUHufZYt+QbOmhrjXiwOAWXAXMYAzHy8gUas8MtzxJGNWqxAA@mail.gmail.com>
Subject: Re: [PATCH 3/3] mm: don't remap clean subpages when splitting
 isolated thp
To:     Matthew Wilcox <willy@infradead.org>
Cc:     Linux-MM <linux-mm@kvack.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Hugh Dickins <hughd@google.com>,
        "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>,
        Vlastimil Babka <vbabka@suse.cz>,
        Yang Shi <shy828301@gmail.com>, Zi Yan <ziy@nvidia.com>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Shuang Zhai <zhais@google.com>
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On Tue, Aug 3, 2021 at 5:38 AM Matthew Wilcox <willy@infradead.org> wrote:
>
> On Sat, Jul 31, 2021 at 12:39:38AM -0600, Yu Zhao wrote:
> > +++ b/include/linux/rmap.h
> > @@ -243,7 +243,7 @@ int page_mkclean(struct page *);
> >   */
> >  void page_mlock(struct page *page);
> >
> > -void remove_migration_ptes(struct page *old, struct page *new, bool locked);
> > +void remove_migration_ptes(struct page *old, struct page *new, bool locked, bool unmap_clean);
>
> I'm not a big fan of 'bool, bool'.  Could we use a flag word instead?
>
> #define MIGRATE_REMOVE_LOCKED   1
> #define MIGRATE_UNMAP_CLEAN     2

Will do. Thanks.