Re: [PATCH] mm: sparse: clarify a variable name and its value

From: Mike Rapoport
Date: Mon Jun 10 2024 - 02:08:50 EST


On Mon, Jun 10, 2024 at 12:39:28PM +0900, Leesoo Ahn wrote:
> 2024년 6월 10일 (월) 오전 6:03, Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>님이 작성:
> >
> > On Sun, 9 Jun 2024 00:21:14 +0900 Leesoo Ahn <lsahn@xxxxxxxxxx> 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.

It is :-P

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

Using MEMBLOCK_ALLOC_ACCESSIBLE is a slight improvement, but renaming the
variable is not, IMO.

> Best regards,
> Leesoo

--
Sincerely yours,
Mike.