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Message-ID: <1d075dad-d0f3-c4c3-d169-89e7b166ea53@suse.cz>
Date:   Thu, 24 Nov 2022 10:00:38 +0100
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Subject: Re: [PATCH 03/12] mm, slub: disable SYSFS support with
 CONFIG_SLUB_TINY
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To:     Roman Gushchin <roman.gushchin@linux.dev>
Cc:     Christoph Lameter <cl@linux.com>,
        David Rientjes <rientjes@google.com>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>,
        Pekka Enberg <penberg@kernel.org>,
        Hyeonggon Yoo <42.hyeyoo@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Matthew Wilcox <willy@infradead.org>, patches@lists.linux.dev,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org
References: <20221121171202.22080-1-vbabka@suse.cz>
 <20221121171202.22080-4-vbabka@suse.cz>
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From:   Vlastimil Babka <vbabka@suse.cz>
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On 11/24/22 02:12, Roman Gushchin wrote:
> On Mon, Nov 21, 2022 at 06:11:53PM +0100, Vlastimil Babka wrote:
>> Currently SLUB enables its sysfs support depending unconditionally on
>> the general CONFIG_SYSFS setting. To reduce the configuration
>> combination space, make CONFIG_SLUB_TINY disable SLUB's sysfs support by
>> reusing the existing SLAB_SUPPORTS_SYSFS define. It is unlikely that
>> real tiny systems would combine CONFIG_SLUB_TINY with CONFIG_SYSFS, but
>> a randconfig might.
> 
> Hm, don't we want to introduce CONFIG_SLAB_SYSFS instead?
> I believe many users don't really need it, even if they don't
> need CONFIG_SLUB_TINY and they do have CONFIG_SYSFS.

Dunno, adding more and more config options is generally frowned upon. Also
tools might be using it to get more details than /proc/slabinfo does - i.e.
tools/vm/slabinfo.c

> Thanks!