Re: [PATCH 00/14] Small step toward KSM for file back page.

[Jerome Glisse]

On Wed, Oct 07, 2020 at 04:20:13AM +0100, Matthew Wilcox wrote:
> On Tue, Oct 06, 2020 at 09:05:49PM -0400, jglisse@xxxxxxxxxx wrote:
> > The present patchset just add mapping argument to the various vfs call-
> > backs. It does not make use of that new parameter to avoid regression.
> > I am posting this whole things as small contain patchset as it is rather
> > big and i would like to make progress step by step.
> 
> Well, that's the problem.  This patch set is gigantic and unreviewable.
> And it has no benefits.  The idea you present here was discussed at
> LSFMM in Utah and I recall absolutely nobody being in favour of it.
> You claim many wonderful features will be unlocked by this, but I think
> they can all be achieved without doing any of this very disruptive work.

You have any ideas on how to achieve them without such change ? I will
be more than happy for a simpler solution but i fail to see how you can
work around the need for a pointer inside struct page. Given struct
page can not grow it means you need to be able to overload one of the
existing field, at least i do not see any otherway.

Cheers,
Jérôme