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Date:   Thu, 10 Sep 2020 09:23:31 +0200
From:   Michal Hocko <mhocko@suse.com>
To:     Laurent Dufour <ldufour@linux.ibm.com>
Cc:     akpm@linux-foundation.org, David Hildenbrand <david@redhat.com>,
        Oscar Salvador <osalvador@suse.de>, rafael@kernel.org,
        nathanl@linux.ibm.com, cheloha@linux.ibm.com,
        stable@vger.kernel.org,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        linux-mm@kvack.org, LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] mm: don't rely on system state to detect hot-plug
 operations
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On Wed 09-09-20 18:07:15, Laurent Dufour wrote:
> Le 09/09/2020 ? 12:59, Michal Hocko a ?crit?:
> > On Wed 09-09-20 11:21:58, Laurent Dufour wrote:
[...]
> > > For the point a, using the enum allows to know in
> > > register_mem_sect_under_node() if the link operation is due to a hotplug
> > > operation or done at boot time.
> > 
> > Yes, but let me repeat. We have a mess here and different paths check
> > for the very same condition by different ways. We need to unify those.
> 
> What are you suggesting to unify these checks (using a MP_* enum as
> suggested by David, something else)?

We do have system_state check spread at different places. I would use
this one and wrap it behind a helper. Or have I missed any reason why
that wouldn't work for this case?

-- 
Michal Hocko
SUSE Labs