Re: [v3 PATCH 2/4] mm: move mem_cgroup_uncharge out of __page_cache_release()

From: Yang Shi
Date: Tue Jun 25 2019 - 11:49:48 EST




On 6/25/19 2:35 AM, Kirill A. Shutemov wrote:
On Mon, Jun 24, 2019 at 09:54:05AM -0700, Yang Shi wrote:

On 6/13/19 10:13 AM, Yang Shi wrote:

On 6/13/19 4:39 AM, Kirill A. Shutemov wrote:
On Thu, Jun 13, 2019 at 05:56:47AM +0800, Yang Shi wrote:
The later patch would make THP deferred split shrinker memcg aware, but
it needs page->mem_cgroup information in THP destructor, which
is called
after mem_cgroup_uncharge() now.

So, move mem_cgroup_uncharge() from __page_cache_release() to compound
page destructor, which is called by both THP and other compound pages
except HugeTLB. And call it in __put_single_page() for single order
page.
If I read the patch correctly, it will change behaviour for pages with
NULL_COMPOUND_DTOR. Have you considered it? Are you sure it will not
break
anything?
Hi Kirill,

Did this solve your concern? Any more comments on this series?
Everyting looks good now. You can use my

Acked-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>

for the series.

Thanks!