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Date:   Thu, 17 Feb 2022 12:54:54 +0800
From:   Peter Xu <peterx@redhat.com>
To:     John Hubbard <jhubbard@nvidia.com>
Cc:     linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        Andrew Morton <akpm@linux-foundation.org>,
        "Kirill A . Shutemov" <kirill@shutemov.name>,
        Matthew Wilcox <willy@infradead.org>,
        Yang Shi <shy828301@gmail.com>,
        Andrea Arcangeli <aarcange@redhat.com>,
        Alistair Popple <apopple@nvidia.com>,
        David Hildenbrand <david@redhat.com>,
        Vlastimil Babka <vbabka@suse.cz>,
        Hugh Dickins <hughd@google.com>
Subject: Re: [PATCH v4 4/4] mm: Rework swap handling of zap_pte_range
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References: <20220216094810.60572-1-peterx@redhat.com>
 <20220216094810.60572-5-peterx@redhat.com>
 <b04fabea-6216-3808-44e8-0a2125bf0230@nvidia.com>
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On Wed, Feb 16, 2022 at 07:25:14PM -0800, John Hubbard wrote:
> On 2/16/22 1:48 AM, Peter Xu wrote:
> > Clean the code up by merging the device private/exclusive swap entry handling
> > with the rest, then we merge the pte clear operation too.
> 
> Maybe also mention that you reduced the code duplication in the 
> is_device_private_entry() area, by letting it fall through to the common
> pte_clear_not_present_full() at the end of the loop? Since you're listing
> the other changes, that one seems worth mentioning.

Isn't that the "we merge the pte clear operation" part? :)

I can add another sentence to it, if it looks better to you:

---8<---
Clean the code up by merging the device private/exclusive swap entry
handling with the rest, then we merge the pte clear operation too.  We do
it by letting the private/exclusive block fall through to the last call to
pte_clear_not_present_full().
---8<---

Thanks for the review,

-- 
Peter Xu