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Message-ID: <c9d0f1b9-dbc7-ddf2-18f9-2b1a991d4932@linux.alibaba.com>
Date:   Mon, 30 May 2022 18:14:45 +0800
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Subject: Re: [RFC PATCH 2/3] hugetlb: do not update address in
 huge_pmd_unshare
To:     Mike Kravetz <mike.kravetz@oracle.com>,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org
Cc:     Muchun Song <songmuchun@bytedance.com>,
        Michal Hocko <mhocko@suse.com>, Peter Xu <peterx@redhat.com>,
        Naoya Horiguchi <naoya.horiguchi@linux.dev>,
        James Houghton <jthoughton@google.com>,
        Mina Almasry <almasrymina@google.com>,
        "Aneesh Kumar K . V" <aneesh.kumar@linux.vnet.ibm.com>,
        Anshuman Khandual <anshuman.khandual@arm.com>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        Christian Borntraeger <borntraeger@linux.ibm.com>,
        Andrew Morton <akpm@linux-foundation.org>
References: <20220527225849.284839-1-mike.kravetz@oracle.com>
 <20220527225849.284839-3-mike.kravetz@oracle.com>
From:   Baolin Wang <baolin.wang@linux.alibaba.com>
In-Reply-To: <20220527225849.284839-3-mike.kravetz@oracle.com>
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On 5/28/2022 6:58 AM, Mike Kravetz wrote:
> As an optimization for loops sequentially processing hugetlb address
> ranges, huge_pmd_unshare would update a passed address if it unshared a
> pmd.  Updating a loop control variable outside the loop like this is
> generally a bad idea.  These loops are now using hugetlb_mask_last_hp
> to optimize scanning when non-present ptes are discovered.  The same
> can be done when huge_pmd_unshare returns 1 indicating a pmd was
> unshared.
> 
> Remove address update from huge_pmd_unshare.  Change the passed argument
> type and update all callers.  In loops sequentially processing addresses
> use hugetlb_mask_last_hp to update address if pmd is unshared.
> 
> Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>

LGTM. Please feel free to add:
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>