Re: [PATCH v8 0/8] mm: Hot page tracking and promotion infrastructure
From: Gregory Price
Date: Fri Sep 25 2026 - 13:04:25 EST
On Fri, Sep 25, 2026 at 09:30:51AM -0700, Davidlohr Bueso wrote:
> > +/**
> > + * damos_add_folios - Add a list of folios as highest priority target for given
> > + * damos.
> > + * @scheme: DAMOS scheme for the specific access-aware operation.
> > + * @folios: List of folios to apply the access-aware operation.
> > + *
> > + * If a kernel component finds folios that eligible for a specific memory
> > + * management operation (e.g., CXL-promotion or demotion), execution of the
> > + * operation can be requested to be done by DAMOS using this function. The
> > + * execution of the operation will be asynchronously done by DAMOS worker
> > + * thread. DAMOS features for resource control (DAMOS quotas) will also be
> > + * applied.
> > + */
> > +void damos_add_folios(struct damos *scheme, struct list_head *folios)
>
> Considering chmu alone would not justify a generic mm interface, I am more and more
> inclined to go with the chmu <-> DAMON option (I recall your presentation) + do
> NUMAB async (1 and 2) and that would solve most problems in a practical manner.
>
The major pushback on NUMAB async has been that there is no good way to
charge this work to the cgroup.
Shakeel recently posted something that might help:
https://lore.kernel.org/linux-mm/20260924184714.912181-1-shakeel.butt@xxxxxxxxx/#t
But the approach does not generalize for everyone (see Tejun's response,
net rx). May be worth a look for folks.
~Gregory