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Date:   Mon, 12 Jun 2023 13:56:42 -0700
From:   Andrew Morton <akpm@linux-foundation.org>
To:     David Hildenbrand <david@redhat.com>
Cc:     Zhaoyang Huang <huangzhaoyang@gmail.com>,
        "zhaoyang.huang" <zhaoyang.huang@unisoc.com>,
        Matthew Wilcox <willy@infradead.org>,
        Suren Baghdasaryan <surenb@google.com>,
        Minchan Kim <minchan@kernel.org>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, ke.wang@unisoc.com
Subject: Re: [PATCHv5] mm: skip CMA pages when they are not available
Message-Id: <20230612135642.24cef34a2925cdde257c1a50@linux-foundation.org>
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On Mon, 12 Jun 2023 12:01:20 +0200 David Hildenbrand <david@redhat.com> wrote:

> ...
>
> >>
> >> If it's a performance improvement, it would be good to show that it is
> >> an actual improvement worth the churn ...
> > Sorry for the confusion. As for the OOM issue, the previous
> > commit(https://lkml.kernel.org/r/1683782550-25799-1-git-send-email-zhaoyang.huang@unisoc.com)
> > helps to decrease the fail rate from 12/20 to 2/20, which it turn to
> > be 0 when applying this patch.
> 
> Thanks! Can we make that clearer in the patch description? I'm 
> struggling a bit my self to find the right words.
> 
> Something like
> 
> "This change further decreases the chance for wrong OOMs in the presence 
> of a lot of CMA memory."
> 

Great, I added that.

> 
> In any case
> 
> Acked-by: David Hildenbrand <david@redhat.com>
> 

And I'll move this patch into mm-stable.