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Message-ID: <dc453287-015d-fd1c-fe7f-6ee45772d6aa@linux.ibm.com>
Date:   Wed, 26 Oct 2022 13:19:48 +0530
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Subject: Re: [PATCH] mm/vmscan: respect cpuset policy during page demotion
To:     Feng Tang <feng.tang@intel.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Michal Hocko <mhocko@suse.com>, Tejun Heo <tj@kernel.org>,
        Zefan Li <lizefan.x@bytedance.com>,
        Waiman Long <longman@redhat.com>, ying.huang@intel.com,
        linux-mm@kvack.org, cgroups@vger.kernel.org
Cc:     linux-kernel@vger.kernel.org, dave.hansen@intel.com,
        tim.c.chen@intel.com, fengwei.yin@intel.com
References: <20221026074343.6517-1-feng.tang@intel.com>
Content-Language: en-US
From:   Aneesh Kumar K V <aneesh.kumar@linux.ibm.com>
In-Reply-To: <20221026074343.6517-1-feng.tang@intel.com>
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On 10/26/22 1:13 PM, Feng Tang wrote:
> In page reclaim path, memory could be demoted from faster memory tier
> to slower memory tier. Currently, there is no check about cpuset's
> memory policy, that even if the target demotion node is not allowd
> by cpuset, the demotion will still happen, which breaks the cpuset
> semantics.
> 
> So add cpuset policy check in the demotion path and skip demotion
> if the demotion targets are not allowed by cpuset.
> 

What about the vma policy or the task memory policy? Shouldn't we respect
those memory policy restrictions while demoting the page? 

-aneesh