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Date:   Wed, 13 Oct 2021 16:26:28 +0200
From:   Michal Hocko <mhocko@suse.com>
To:     "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc:     linux-mm@kvack.org, akpm@linux-foundation.org,
        Ben Widawsky <ben.widawsky@intel.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Feng Tang <feng.tang@intel.com>,
        Andrea Arcangeli <aarcange@redhat.com>,
        Mel Gorman <mgorman@techsingularity.net>,
        Mike Kravetz <mike.kravetz@oracle.com>,
        Randy Dunlap <rdunlap@infradead.org>,
        Vlastimil Babka <vbabka@suse.cz>,
        Andi Kleen <ak@linux.intel.com>,
        Dan Williams <dan.j.williams@intel.com>,
        Huang Ying <ying.huang@intel.com>, linux-api@vger.kernel.org
Subject: Re: [RFC PATCH] mm/mempolicy: add MPOL_PREFERRED_STRICT memory policy
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On Wed 13-10-21 19:27:03, Aneesh Kumar K.V wrote:
[...]
> Another option is to keep this mbind(2) specific and overload flags to be
> the preferred nodeid.
> 
> mbind(va, len, MPOL_PREFERRED_STRICT, nodemask, max_node, preferred_node);

First of all I do not think you really want to create a new memory
policy for this. Not to mention that PREFERRED_STRICT is kinda weird in
the first place but one could argue that a preference of the first node
to try is not really specific to BIND/PREFERRED_MANY. Overloading flags
is a nogo.

-- 
Michal Hocko
SUSE Labs