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Date:   Tue, 24 Nov 2020 18:50:32 -0800 (PST)
From:   Hugh Dickins <hughd@google.com>
To:     Matthew Wilcox <willy@infradead.org>
cc:     Hugh Dickins <hughd@google.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Jan Kara <jack@suse.cz>,
        William Kucharski <william.kucharski@oracle.com>,
        linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, hch@lst.de,
        hannes@cmpxchg.org, yang.shi@linux.alibaba.com,
        dchinner@redhat.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v4 00/16] Overhaul multi-page lookups for THP
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On Wed, 25 Nov 2020, Matthew Wilcox wrote:
> On Tue, Nov 17, 2020 at 11:43:02PM +0000, Matthew Wilcox wrote:
> > On Tue, Nov 17, 2020 at 07:15:13PM +0000, Matthew Wilcox wrote:
> > > I find both of these functions exceptionally confusing.  Does this
> > > make it easier to understand?
> > 
> > Never mind, this is buggy.  I'll send something better tomorrow.
> 
> That took a week, not a day.  *sigh*.  At least this is shorter.

Thanks, I'll give it a try (along with the other 4, on top of the 12:
maybe on -rc5, maybe on today's mmotm, I'll decide that later).

Shorter you say, that's good: I was disheartened by the way it got
more complicated, after your initial truncate_inode_partial_page()
neatness.  Any hints on what was wrong with my simple fixup to that?
(But I didn't spend any more time trying to prove or disprove it.)

Hugh