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Date:   Wed, 14 Nov 2018 14:23:06 +0100
From:   Michal Hocko <mhocko@kernel.org>
To:     David Rientjes <rientjes@google.com>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        Vlastimil Babka <vbabka@suse.cz>,
        Alexey Dobriyan <adobriyan@gmail.com>,
        "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        linux-api@vger.kernel.org
Subject: Re: [RFC PATCH] mm, proc: report PR_SET_THP_DISABLE in proc
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On Thu 18-10-18 09:00:31, Michal Hocko wrote:
> On Wed 17-10-18 12:59:18, David Rientjes wrote:
> > On Wed, 17 Oct 2018, Michal Hocko wrote:
> > 
> > > Do you know of any other userspace except your usecase? Is there
> > > anything fundamental that would prevent a proper API adoption for you?
> > > 
> > 
> > Yes, it would require us to go back in time and build patched binaries. 
> 
> I read that as there is a fundamental problem to update existing
> binaries. If that is the case then there surely is no way around it
> and another sad page in the screwed up APIs book we provide.
> 
> But I was under impression that the SW stack which actually does the
> monitoring is under your controll. Moreover I was under impression that
> you do not use the current vanilla kernel so there is no need for an
> immediate change on your end. It is trivial to come up with a backward
> compatible way to check for the new flag (if it is not present then
> fallback to vma flags).
> 
> I am sorry for pushing here but if this is just a matter of a _single_
> user which _can_ be fixed with a reasonable effort then I would love to
> see the future api unscrewed.

ping
-- 
Michal Hocko
SUSE Labs