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Sender: Minchan Kim <minchan.kim@gmail.com>
Date:   Wed, 17 Feb 2021 13:22:05 -0800
From:   Minchan Kim <minchan@kernel.org>
To:     Matthew Wilcox <willy@infradead.org>
Cc:     Michal Hocko <mhocko@suse.com>,
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Subject: Re: [RFC 1/2] mm: disable LRU pagevec during the migration
 temporarily
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On Wed, Feb 17, 2021 at 09:11:43PM +0000, Matthew Wilcox wrote:
> On Wed, Feb 17, 2021 at 12:51:25PM -0800, Minchan Kim wrote:
> > I'd like to avoid atomic operation if we could.
> 
> Why do you think that the spinlock is better?
> 

Michal suggested atomic_inc in writeside and atomic_read in readside.
I wanted to avoid atomic operation in readside path.

You are suggesting atomic for writeside and just read(not atomic_read)
in readside?