Message-ID: <59630801-42b4-22e8-0ef6-5a5b8636dfbd@redhat.com>
Date:   Fri, 3 Feb 2023 17:04:01 +0100
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Subject: Re: [RFC v3 2/4] mm: move PG_slab flag to page_type
To:     Matthew Wilcox <willy@infradead.org>,
        Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc:     Vlastimil Babka <vbabka@suse.cz>, Christoph Lameter <cl@linux.com>,
        Pekka Enberg <penberg@kernel.org>,
        David Rientjes <rientjes@google.com>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Roman Gushchin <roman.gushchin@linux.dev>,
        =?UTF-8?B?SE9SSUdVQ0hJIE5BT1lBKOWggOWPoyDnm7TkuZ8p?= 
        <naoya.horiguchi@nec.com>, Joe Perches <joe@perches.com>,
        Petr Mladek <pmladek@suse.com>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        Alexander Potapenko <glider@google.com>,
        Marco Elver <elver@google.com>
References: <20221218101901.373450-1-42.hyeyoo@gmail.com>
 <20221218101901.373450-3-42.hyeyoo@gmail.com>
 <15fda061-72d9-2ee9-0e9f-6f0f732a7382@suse.cz> <Y9dI88l2YJZfZ8ny@hyeyoo>
 <Y9dRlNhh6O99tg4E@casper.infradead.org>
Content-Language: en-US
From:   David Hildenbrand <david@redhat.com>
Organization: Red Hat
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On 30.01.23 06:11, Matthew Wilcox wrote:
> On Mon, Jan 30, 2023 at 01:34:59PM +0900, Hyeonggon Yoo wrote:
>>> Seems like quite some changes to page_type to accomodate SLAB, which is
>>> hopefully going away soon(TM). Could we perhaps avoid that?
>>
>> If it could be done with less changes, I'll try to avoid that.
> 
> Let me outline the idea I had for removing PG_slab:
> 
> Observe that PG_reserved and PG_slab are mutually exclusive.  Also,

I recall that there are SetPageReserved() calls on pages allocated via slab.

-- 
Thanks,

David / dhildenb