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Message-ID: <efd4c141-8c09-4787-b820-aecf2ad02ef5@gmail.com>
Date: Mon, 25 Mar 2024 20:40:03 +0800
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Subject: Re: [PATCH v2 13/14] mm/ksm: use folio_set_stable_node in
 try_to_merge_one_page
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To: Matthew Wilcox <willy@infradead.org>, alexs@kernel.org
Cc: Andrea Arcangeli <aarcange@redhat.com>,
 Izik Eidus <izik.eidus@ravellosystems.com>, david@redhat.com,
 Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org,
 linux-kernel@vger.kernel.org, Hugh Dickins <hughd@google.com>,
 Chris Wright <chrisw@sous-sol.org>
References: <20240322083703.232364-1-alexs@kernel.org>
 <20240322083703.232364-14-alexs@kernel.org>
 <Zf5OvWFiYjs_ZCF2@casper.infradead.org>
From: Alex Shi <seakeel@gmail.com>
In-Reply-To: <Zf5OvWFiYjs_ZCF2@casper.infradead.org>
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On 3/23/24 11:38 AM, Matthew Wilcox wrote:
> On Fri, Mar 22, 2024 at 04:37:00PM +0800, alexs@kernel.org wrote:
>> From: "Alex Shi (tencent)" <alexs@kernel.org>
>>
>> Only single page could be reached where we set stable node after write
>> protect, so use folio converted func to replace page's.
>>
>> Signed-off-by: Alex Shi (tencent) <alexs@kernel.org>
>> Cc: Izik Eidus <izik.eidus@ravellosystems.com>
>> Cc: Matthew Wilcox <willy@infradead.org>
>> Cc: Andrea Arcangeli <aarcange@redhat.com>
>> Cc: Hugh Dickins <hughd@google.com>
>> Cc: Chris Wright <chrisw@sous-sol.org>
>> ---
>>  mm/ksm.c | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/mm/ksm.c b/mm/ksm.c
>> index 15a78a9bab59..d7c4cc4a0cc1 100644
>> --- a/mm/ksm.c
>> +++ b/mm/ksm.c
>> @@ -1518,7 +1518,7 @@ static int try_to_merge_one_page(struct vm_area_struct *vma,
>>  			 * PageAnon+anon_vma to PageKsm+NULL stable_node:
>>  			 * stable_tree_insert() will update stable_node.
>>  			 */
>> -			set_page_stable_node(page, NULL);
>> +			folio_set_stable_node(page_folio(page), NULL);
>>  			mark_page_accessed(page);
> 
> I'd rather you did a conversion of try_to_merge_one_page() instead of
> just this.  It'll be a fun one because you'll have to recalculate the
> folio after calling split_huge_page().

Hi Willy,

Definitely right, the merge series funcs need more careful changes. :)
I'd like to left them for late changes.

Thanks