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References: <20240608152114.867961-1-lsahn@wewakecorp.com> <20240609140341.14ba3a1c62029771d60059ed@linux-foundation.org>
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From: Leesoo Ahn <lsahn@ooseel.net>
Date: Mon, 10 Jun 2024 12:39:28 +0900
Message-ID: <CANTT7qjthRWX+7m749mU_CmGUO1UEvY6O9yKsStm165Lz=tqAQ@mail.gmail.com>
Subject: Re: [PATCH] mm: sparse: clarify a variable name and its value
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Leesoo Ahn <lsahn@wewakecorp.com>, linux-mm@kvack.org, linux-kernel@vger.kernel.org, 
	Mike Rapoport <rppt@kernel.org>
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2024=EB=85=84 6=EC=9B=94 10=EC=9D=BC (=EC=9B=94) =EC=98=A4=EC=A0=84 6:03, A=
ndrew Morton <akpm@linux-foundation.org>=EB=8B=98=EC=9D=B4 =EC=9E=91=EC=84=
=B1:
>
> On Sun,  9 Jun 2024 00:21:14 +0900 Leesoo Ahn <lsahn@ooseel.net> wrote:
>
> > Setting 'limit' variable to 0 might seem like it means "no limit". But
> > in the memblock API, 0 actually means the 'MEMBLOCK_ALLOC_ACCESSIBLE'
> > enum, which limits the physical address range based on
> > 'memblock.current_limit'. This can be confusing.
>
> Does it?  From my reading, this meaning applies to the range end
> address, in memblock_find_in_range_node()?  If your interpretation is
> correct, this should be documented in the relevant memblock kerneldoc.

IMO, regardless of memblock documentation, it better uses
MEMBLOCK_ALLOC_ACCESSIBLE enum instead of 0 as a value for the variable.

Best regards,
Leesoo