Re: [PATCHv19 00/15] Contiguous Memory Allocator

Mel Gorman
2012-01-30T13:25:16Z

On Fri, Jan 27, 2012 at 04:26:24PM -0800, Andrew Morton wrote:
> On Thu, 26 Jan 2012 15:31:40 +0000
> Arnd Bergmann <arnd@arndb.de> wrote:
>
> > On Thursday 26 January 2012, Marek Szyprowski wrote:
> > > Welcome everyone!
> > >
> > > Yes, that's true. This is yet another release of the Contiguous Memory
> > > Allocator patches. This version mainly includes code cleanups requested
> > > by Mel Gorman and a few minor bug fixes.
> >
> > Hi Marek,
> >
> > Thanks for keeping up this work! I really hope it works out for the
> > next merge window.
>
> Someone please tell me when it's time to start paying attention
> again ;)
>
> These patches don't seem to have as many acked-bys and reviewed-bys as
> I'd expect.

I reviewed the core MM changes and I've acked most of them so the
next release should have a few acks where you expect them. I did not
add a reviewed-by because I did not build and test the thing.

For me, Patch 2 is the only one that must be fixed prior to merging
as it can interfere with pages on a remote per-cpu list which is
dangerous. I know your suggestion will be to delete the per-cpu lists
and be done with it but I am a bit away from doing that just yet.

Patch 8 could do with a bit more care too but it is not a
potential hand grenade like patch 2 and could be fixed as part of
a follow-up. Even if you don't see an ack from me there, it should not
be treated as a show stopper.

I highlighted some issues on how CMA interacts with reclaim but I
think this is a problem specific to CMA and should not prevent it being
merged. I just wanted to be sure that the CMA people were aware of the
potential issues so they will recognise the class of bug if it occurs.

> Given the scope and duration of this, it would be useful
> to gather these up. But please ensure they are real ones - people
> sometimes like to ack things without showing much sign of having
> actually read them.
>

FWIW, the acks I put on the core MM changes are real acks :)

> The patches do seem to have been going round in ever-decreasing circles
> lately and I think we have decided to merge them (yes?) so we may as well
> get on and do that and sort out remaining issues in-tree.
>

I'm a lot happier with the core MM patches than I was when I reviewed
this first around last September or October.

--
Mel Gorman
SUSE Labs