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Subject: Re: [PATCHv3] mm/pageblock: throw compiling time error if
 pageblock_bits can not hold MIGRATE_TYPES
References: <1544508709-11358-1-git-send-email-kernelfans@gmail.com>
From: Vlastimil Babka <vbabka@suse.cz>
Message-ID: <f11c25b0-2933-cc1a-aeb4-c7fbb462ac5f@suse.cz>
Date: Fri, 14 Dec 2018 12:22:22 +0100
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Sender: owner-linux-mm@kvack.org
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To: Pingfan Liu <kernelfans@gmail.com>, linux-mm@kvack.org
Cc: Andrew Morton <akpm@linux-foundation.org>, Michal Hocko <mhocko@suse.com>, Pavel Tatashin <pavel.tatashin@microsoft.com>, Oscar Salvador <osalvador@suse.de>, Mike Rapoport <rppt@linux.vnet.ibm.com>, Joonsoo Kim <iamjoonsoo.kim@lge.com>, Alexander Duyck <alexander.h.duyck@linux.intel.com>

On 12/11/18 7:11 AM, Pingfan Liu wrote:
> Currently, NR_PAGEBLOCK_BITS and MIGRATE_TYPES are not associated by code.
> If someone adds extra migrate type, then he may forget to enlarge the
> NR_PAGEBLOCK_BITS. Hence it requires some way to fix.
> NR_PAGEBLOCK_BITS depends on MIGRATE_TYPES, while these macro
> spread on two different .h file with reverse dependency, it is a little
> hard to refer to MIGRATE_TYPES in pageblock-flag.h. This patch tries to
> remind such relation in compiling-time.
> 
> Signed-off-by: Pingfan Liu <kernelfans@gmail.com>

Acked-by: Vlastimil Babka <vbabka@suse.cz>