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Date:   Tue, 24 Mar 2020 12:17:11 -0700 (PDT)
From:   David Rientjes <rientjes@google.com>
To:     "Kirill A. Shutemov" <kirill@shutemov.name>
cc:     Hui Zhu <teawater@gmail.com>, hannes@cmpxchg.org,
        mhocko@kernel.org, vdavydov.dev@gmail.com,
        akpm@linux-foundation.org, hughd@google.com,
        yang.shi@linux.alibaba.com, dan.j.williams@intel.com,
        aneesh.kumar@linux.ibm.com, sean.j.christopherson@intel.com,
        thellstrom@vmware.com, guro@fb.com, shakeelb@google.com,
        chris@chrisdown.name, tj@kernel.org, tglx@linutronix.de,
        linux-kernel@vger.kernel.org, cgroups@vger.kernel.org,
        linux-mm@kvack.org, Hui Zhu <teawaterz@linux.alibaba.com>
Subject: Re: [PATCH] mm, memcg: Add memory.transparent_hugepage_disabled
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On Tue, 24 Mar 2020, Kirill A. Shutemov wrote:

> On Tue, Mar 24, 2020 at 06:31:56PM +0800, Hui Zhu wrote:
> > /sys/kernel/mm/transparent_hugepage/enabled is the only interface to
> > control if the application can use THP in system level.
> 
> No. We have prctl(PR_SET_THP_DISABLE) too.
> 

Yeah, I think this is the key point since this can be inherited across 
fork and thus you already have the ability to disable thp for a process 
where you cannot even modify the binary to do MADV_NOHUGEPAGE.