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Date:   Mon, 28 Sep 2020 14:53:51 +0200
From:   Oscar Salvador <osalvador@suse.de>
To:     David Hildenbrand <david@redhat.com>
Cc:     linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        linux-hyperv@vger.kernel.org, xen-devel@lists.xenproject.org,
        linux-acpi@vger.kernel.org,
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        "K. Y. Srinivasan" <kys@microsoft.com>,
        Haiyang Zhang <haiyangz@microsoft.com>,
        Stephen Hemminger <sthemmin@microsoft.com>,
        Wei Liu <wei.liu@kernel.org>
Subject: Re: [PATCH RFC 4/4] mm/page_alloc: place pages to tail in
 __free_pages_core()
Message-ID: <20200928125346.GA7703@linux>
References: <20200916183411.64756-1-david@redhat.com>
 <20200916183411.64756-5-david@redhat.com>
 <20200928075820.GA4082@linux>
 <a18327c0-b86a-df00-e984-27c26468caf7@redhat.com>
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On Mon, Sep 28, 2020 at 10:36:00AM +0200, David Hildenbrand wrote:
> Hi Oscar!

Hi David :-)

> 
> Old code:
> 
> set_page_refcounted(): sets the refcount to 1.
> __free_pages()
>   -> put_page_testzero(): sets it to 0
>   -> free_the_page()->__free_pages_ok()
> 
> New code:
> 
> set_page_refcounted(): sets the refcount to 1.
> page_ref_dec(page): sets it to 0
> __free_pages_ok():

bleh, I misread the patch, somehow I managed to not see that you replaced
__free_pages with __free_pages_ok.

To be honest, now that we do not need the page's refcount to be 1 for the
put_page_testzero to trigger (and since you are decrementing it anyways),
I think it would be much clear for those two to be gone.

But not strong, so:

Reviewed-by: Oscar Salvador <osalvador@suse.de>

-- 
Oscar Salvador
SUSE L3