Re: [PATCH v2 0/7] mm: Page fault enhancements

From: Linus Torvalds
Date: Thu Sep 05 2019 - 17:11:28 EST


On Thu, Sep 5, 2019 at 3:15 AM Peter Xu <peterx@xxxxxxxxxx> wrote:
>
> This series is split out of userfaultfd-wp series to only cover the
> general page fault changes, since it seems to make sense itself.

The series continues to look sane to me, but I'd like VM people to
take a look. I see a few reviewed-by's, it would be nice to see more
comments from people. I'd like to see Andrea in particular say "yeah,
this looks all good to me".

Also a question on how this will get to me - it smells like Andrew's
-mm tree to me, both from a VM and a userfaultfd angle (and looking
around, at least a couple of previous patches by Peter have gone that
way).

And it would be lovely to have actual _numbers_ for the alleged
latency improvements. I 100% believe them, but still, numbers rule.

Talking about latency, what about that retry loop in gup()? That's the
one I'm not at all convinced about. It doesn't check for signals, so
if there is some retry logic, it loops forever. Hmm?

Linus