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Date: Tue, 27 May 2014 15:09:26 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Vlastimil Babka <vbabka@suse.cz>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>,
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        Mike Marciniszyn <infinipath@intel.com>
Subject: Re: [RFC][PATCH 0/5] VM_PINNED
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On Tue, May 27, 2014 at 01:50:47PM +0200, Vlastimil Babka wrote:
> > What if VM_PINNED will require VM_LOCKED?
> > I.e. user must mlock it before pining and cannot munlock vma while it's pinned.
> 
> Mlocking makes sense, as pages won't be uselessly scanned on
> non-evictable LRU, no? (Or maybe I just don't see that something else
> prevents then from being there already).

We can add VM_PINNED logic to page_check_reference() and
try_to_unmap_one() to avoid the scanning if that's a problem. But that's
additional bits.