Re: [PATCH v4] page_alloc: consider highatomic reserve in watermark fast

From: yong w <yongw.pur@gmail.com>
To: jaewon31.kim@samsung.com
Cc: Greg KH <gregkh@linuxfoundation.org>,
	"mhocko@kernel.org" <mhocko@kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"stable@vger.kernel.org" <stable@vger.kernel.org>,
	"wang.yong12@zte.com.cn" <wang.yong12@zte.com.cn>,
	YongTaek Lee <ytk.lee@samsung.com>
Subject: Re: [PATCH v4] page_alloc: consider highatomic reserve in watermark fast
Date: Mon, 19 Sep 2022 21:21:16 +0800	[thread overview]
Message-ID: <CAOH5QeCF2HfGTJHue4GM6r7K3cec4xfReifVOuB_H4Fi6nXupg@mail.gmail.com> (raw)
In-Reply-To: <1891546521.01663549682346.JavaMail.epsvc@epcpadp4>

Jaewon Kim <jaewon31.kim@samsung.com> 于2022年9月19日周一 09:08写道：
>
> >On Wed, Sep 14, 2022 at 08:46:15AM +0800, yong w wrote:
> >> Greg KH <gregkh@linuxfoundation.org> 于2022年9月13日周二 21:54?道：
> >>
> >> >
> >> > On Tue, Sep 13, 2022 at 09:09:47PM +0800, yong wrote:
> >> > > Hello,
> >> > > This patch is required to be patched in linux-5.4.y and linux-4.19.y.
> >> >
> >> > What is "this patch"?  There is no context here :(
> >> >
> >> Sorry, I forgot to quote the original patch. the patch is as follows
> >>
> >>     f27ce0e page_alloc: consider highatomic reserve in watermark fast
> >>
> >> > > In addition to that, the following two patches are somewhat related:
> >> > >
> >> > >       3334a45 mm/page_alloc: use ac->high_zoneidx for classzone_idx
> >> > >       9282012 page_alloc: fix invalid watermark check on a negative value
> >> >
> >> > In what way?  What should be done here by us?
> >> >
> >>
> >> I think these two patches should also be merged.
> >>
> >>     The classzone_idx  parameter is used in the zone_watermark_fast
> >> functionzone, and 3334a45 use ac->high_zoneidx for classzone_idx.
> >>     "9282012 page_alloc: fix invalid watermark check on a negative
> >> value"  fix f27ce0e introduced issues
> >
> >Ok, I need an ack by all the developers involved in those commits, as
> >well as the subsystem maintainer so that I know it's ok to take them.
> >
> >Can you provide a series of backported and tested patches so that they
> >are easy to review?
> >
> >thanks,
> >
> >greg k-h
>
> Hello I didn't know my Act is needed to merge it.
>
> Acked-by: Jaewon Kim <jaewon31.kim@samsung.com>
>
> I don't understand well why the commit f27ce0e has dependency on 3334a45, though.
>
Hello, the classzone_idx is used in the zone_watermark_fast function, and
there will be conflicts when f27ce0e is merged.

Looking back, the following two patches adjust the classzone_idx parameter.
     3334a45 mm/page_alloc: use ac->high_zoneidx for classzone_idx
     97a225e mm/page_alloc: integrate classzone_idx and high_zoneidx
and 3334a45 is the key modification.

Actually, I think 3334a45 can be merged or not.

Thanks.