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Message-ID: <0c2fac38720710aebe2b667807c647e8a5aa5441.camel@linux.intel.com>
Subject: Re: [PATCH v5 6/9] mm/demotion: Add support for removing node from
 demotion memory tiers
From:   Tim Chen <tim.c.chen@linux.intel.com>
To:     "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>,
        linux-mm@kvack.org, akpm@linux-foundation.org
Cc:     Wei Xu <weixugc@google.com>, Huang Ying <ying.huang@intel.com>,
        Greg Thelen <gthelen@google.com>,
        Yang Shi <shy828301@gmail.com>,
        Davidlohr Bueso <dave@stgolabs.net>,
        Tim C Chen <tim.c.chen@intel.com>,
        Brice Goglin <brice.goglin@gmail.com>,
        Michal Hocko <mhocko@kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Hesham Almatary <hesham.almatary@huawei.com>,
        Dave Hansen <dave.hansen@intel.com>,
        Jonathan Cameron <Jonathan.Cameron@huawei.com>,
        Alistair Popple <apopple@nvidia.com>,
        Dan Williams <dan.j.williams@intel.com>,
        Feng Tang <feng.tang@intel.com>,
        Jagdish Gediya <jvgediya@linux.ibm.com>,
        Baolin Wang <baolin.wang@linux.alibaba.com>,
        David Rientjes <rientjes@google.com>
Date:   Tue, 07 Jun 2022 16:40:00 -0700
In-Reply-To: <20220603134237.131362-7-aneesh.kumar@linux.ibm.com>
References: <20220603134237.131362-1-aneesh.kumar@linux.ibm.com>
         <20220603134237.131362-7-aneesh.kumar@linux.ibm.com>
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On Fri, 2022-06-03 at 19:12 +0530, Aneesh Kumar K.V wrote:
> This patch adds the special string "none" as a supported memtier value
> that we can use to remove a specific node from being using as demotion target.

And also such node will not participate in promotion.  That is, hot memory in it will
not be promoted to other nodes.

> 
> For ex:
> :/sys/devices/system/node/node1# cat memtier
> 1
> :/sys/devices/system/node/node1# cat ../../memtier/memtier1/nodelist
> 1-3
> :/sys/devices/system/node/node1# echo none > memtier
> :/sys/devices/system/node/node1#
> :/sys/devices/system/node/node1# cat memtier
> :/sys/devices/system/node/node1# cat ../../memtier/memtier1/nodelist
> 2-3
> :/sys/devices/system/node/node1#
> 
>