Re: [PATCH v2 1/4] Make place for common balloon code

[Ritesh Harjani <ritesh.list@gmail.com>]

On 22/08/16 12:41PM, Alexander Atanasov wrote:
> File already contains code that is common along balloon
> drivers so rename it to reflect its contents.
> mm/balloon_compaction.c -> mm/balloon_common.c
>
> Signed-off-by: Alexander Atanasov <alexander.atanasov@virtuozzo.com>
> ---
>  MAINTAINERS                                              | 4 ++--
>  arch/powerpc/platforms/pseries/cmm.c                     | 2 +-
>  drivers/misc/vmw_balloon.c                               | 2 +-
>  drivers/virtio/virtio_balloon.c                          | 2 +-
>  include/linux/{balloon_compaction.h => balloon_common.h} | 2 +-
>  mm/Makefile                                              | 2 +-
>  mm/{balloon_compaction.c => balloon_common.c}            | 4 ++--

>  mm/migrate.c                                             | 2 +-
>  mm/vmscan.c                                              | 2 +-
I think we don't need balloon headers in above two files at all.
I don't see any references of balloon functions in them.

I guess this commit removed it -

commit b1123ea6d3b3da25af5c8a9d843bd07ab63213f4
Author: Minchan Kim <minchan@kernel.org>
Date:   Tue Jul 26 15:23:09 2016 -0700

    mm: balloon: use general non-lru movable page feature

    Now, VM has a feature to migrate non-lru movable pages so balloon
    doesn't need custom migration hooks in migrate.c and compaction.c.

    Instead, this patch implements the page->mapping->a_ops->
    {isolate|migrate|putback} functions.

    With that, we could remove hooks for ballooning in general migration
    functions and make balloon compaction simple.

Since I don't often look into this side of code, it's better to confirm :)

-ritesh