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Date:   Tue, 6 Apr 2021 17:21:34 +0300
From:   "Kirill A. Shutemov" <kirill@shutemov.name>
To:     Matthew Wilcox <willy@infradead.org>
Cc:     linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        linux-fsdevel@vger.kernel.org, linux-cachefs@redhat.com,
        linux-afs@lists.infradead.org
Subject: Re: [PATCH v6 01/27] mm: Introduce struct folio
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On Tue, Apr 06, 2021 at 01:48:07PM +0100, Matthew Wilcox wrote:
> Now, maybe we should put this optimisation into the definition of nth_page?

Sounds like a good idea to me.

> > > +struct folio {
> > > +	/* private: don't document the anon union */
> > > +	union {
> > > +		struct {
> > > +	/* public: */
> > > +			unsigned long flags;
> > > +			struct list_head lru;
> > > +			struct address_space *mapping;
> > > +			pgoff_t index;
> > > +			unsigned long private;
> > > +			atomic_t _mapcount;
> > > +			atomic_t _refcount;
> > > +#ifdef CONFIG_MEMCG
> > > +			unsigned long memcg_data;
> > > +#endif
> > 
> > As Christoph, I'm not a fan of this :/
> 
> What would you prefer?

I liked earlier approach with only struct page here. Once we know a field
should never be referenced from raw struct page, we can move it here.

But feel free to ignore my suggestion. It's not show-stopper for me and
reverting is back doesn't worth it.

I went through the patchset and it looks good. You can use my

  Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>

on all of them.

Thanks a lot for doing this.

-- 
 Kirill A. Shutemov