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Date:   Thu, 19 Jan 2023 10:07:23 +0100
From:   Michal Hocko <mhocko@suse.com>
To:     Minchan Kim <minchan@kernel.org>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        Suren Baghdasaryan <surenb@google.com>,
        Matthew Wilcox <willy@infradead.org>,
        linux-mm <linux-mm@kvack.org>,
        LKML <linux-kernel@vger.kernel.org>,
        SeongJae Park <sj@kernel.org>
Subject: Re: [PATCH 1/3] mm: return the number of pages successfully paged out
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On Wed 18-01-23 14:27:23, Minchan Kim wrote:
[...]
> Let me know if you have other concern or suggestion.

I would propose to use a tracepoint to track this on the madvise side.
This way you can both track a per-process effectivity as well a madvise
originator effectivity (if the policy is implemented by a global monitor
then it won't get interfering activity by other users of this
interface). Global counters cannot do neither of that.
-- 
Michal Hocko
SUSE Labs