Re: [PATCH 2/9] mm: alloc_contig_freed_pages() added

Michal Nazarewicz
2011-10-16T08:01:42Z

On Sat, 15 Oct 2011 01:29:33 +0200, Andrew Morton <akpm@linux-foundation.org> wrote:

> On Thu, 06 Oct 2011 15:54:42 +0200
> Marek Szyprowski <m.szyprowski@samsung.com> wrote:
>
>> From: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
>>
>> This commit introduces alloc_contig_freed_pages() function
>
> The "freed" seems redundant to me. Wouldn't "alloc_contig_pages" be a
> better name?

The “freed” is there because the function operates on pages that are in
buddy system, ie. it is given a range of PFNs that are to be removed
from buddy system.

There's also a alloc_contig_range() function (added by next patch)
which frees pages in given range and then calls
alloc_contig_free_pages() to allocate them.

IMO, if there was an alloc_contig_pages() function, it would have to
be one level up (ie. it would figure out where to allocate memory and
then call alloc_contig_range()). (That's really what CMA is doing).

Still, as I think of it now, maybe alloc_contig_free_range() would be
better?