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Date:   Wed, 11 Dec 2019 12:43:49 -0800
From:   Matthew Wilcox <willy@infradead.org>
To:     Jens Axboe <axboe@kernel.dk>
Cc:     Linus Torvalds <torvalds@linux-foundation.org>,
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Subject: Re: [PATCHSET v3 0/5] Support for RWF_UNCACHED
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On Wed, Dec 11, 2019 at 01:08:32PM -0700, Jens Axboe wrote:
> > The fact that you see that xas_create() so prominently would imply
> > perhaps add_to_swap_cache(), which certainly implies that the page
> > shrinking isn't hitting the file pages...
> 
> That's presumably misleading, as it's just lookups. But yes,
> confusing...

While xas_create() could be called directly, it's more often called
through xas_store() ... which would be called if we're storing a shadow
entry to replace a page, which this workload would presumably be doing.