Re: [PATCH 00/34] put_user_pages(): miscellaneous call sites

[John Hubbard]

On 8/2/19 1:05 AM, Peter Zijlstra wrote:
> On Thu, Aug 01, 2019 at 07:16:19PM -0700, john.hubbard@xxxxxxxxx wrote:
>
> > This is part a tree-wide conversion, as described in commit fc1d8e7cca2d
> > ("mm: introduce put_user_page*(), placeholder versions"). That commit
> > has an extensive description of the problem and the planned steps to
> > solve it, but the highlites are:
>
> That is one horridly mangled Changelog there :-/ It looks like it's
> partially duplicated.

Yeah. It took so long to merge that I think I was no longer able to
actually see the commit description, after N readings. sigh

> Anyway; no objections to any of that, but I just wanted to mention that
> there are other problems with long term pinning that haven't been
> mentioned, notably they inhibit compaction.
>
> A long time ago I proposed an interface to mark pages as pinned, such
> that we could run compaction before we actually did the pinning.

This is all heading toward marking pages as pinned, so we should finally
get there.  I'll post the RFC for tracking pinned pages shortly.


thanks,
--
John Hubbard
NVIDIA