Re: [RFC PATCH 0/3] mm/compaction: honour compact_unevictable_allowed in mlock race and alloc_contig path

From: Lorenzo Stoakes

Date: Wed Jul 08 2026 - 02:42:17 EST


On Wed, Jul 08, 2026 at 07:31:26AM +0100, Lorenzo Stoakes wrote:
> Errr... how does this relate to your other, non-RFC patch series [0] "mm: honour
> compact_unevictable_allowed in mlock and CMA paths"?
>
> Why did you send this separately and why do you not mention the other series
> here or there?
>
> And why is one RFC and the other not?
>
> You really need to add more context like this, I spent quite a bit of time
> reviewing [0] and don't want to find out that actually you are abandoning that
> for this or something?...

Oh hang on... this is old, and [0] is new, my bad.

It just got pinged up my mail client because of recent replies :>)

Thanks, Lorenzo

>
> On Thu, Jun 04, 2026 at 10:38:09AM +0800, Wandun Chen wrote:
> > From: Wandun Chen <chenwandun@xxxxxxxxxxx>
> >
> > vm.compact_unevictable_allowed=0 is meant to keep compaction from
> > touching unevictable folios. In practice there are still two paths
> > where it does not take effect. This series fixes them and adds a
> > tracepoint to make such issues easier to diagnose in the future.
> >
> > Wandun Chen (3):
> > mm/compaction: skip isolate mlocked folios when
> > compact_unevictable_allowed=0
> > mm/compaction: add per-folio isolation tracepoint
> > mm/compaction: respect compact_unevictable_allowed in alloc_contig
> > path
> >
> > include/linux/compaction.h | 6 ++++++
> > include/trace/events/compaction.h | 26 ++++++++++++++++++++++++++
> > mm/compaction.c | 14 +++++++++++---
> > mm/internal.h | 1 +
> > mm/page_alloc.c | 2 ++
> > 5 files changed, 46 insertions(+), 3 deletions(-)
> >
> > --
> > 2.43.0
> >
>
> Thanks, Lorenzo
>
> [0]:https://lore.kernel.org/all/20260707125925.3725177-1-chenwandun1@xxxxxxxxx/