[RFC PATCH 0/4] mm/damon: add DAMOS_MIGRATE_{HOT,COLD} destination nodes and weights

[SeongJae Park <sj@kernel.org>]

DAMOS_MIGRATE_{HOT,COLD} action can migrate pages to only single node.
It could be useful to allow it migrates pages to multiple nodes with
different weights.  A work for dynamic interleaving[1] is in progress.
We also discussed this could be useful for memory tiering, e.g., when we
want to move pages to multiple noes of same tier.

Extend the API and ABI interface for specifying the multiple destination
nodes and their weights.

Note that this RFC is a prototype of the interface change for Bijan's
interleaving work[1].  Hence this patch series is only implementing the
interface part, not the real implementation of the migration behavior.

[1] https://lore.kernel.org/20250620180458.5041-1-bijan311@gmail.com
[2] https://lore.kernel.org/20240408175228.91414-1-sj@kernel.org

SeongJae Park (4):
  mm/damon: add struct damos_migrate_dest
  mm/damon/core: add damos->migrate_dest field
  mm/damon/sysfs-schemes: implement DAMOS action destinations directory
  mm/damon/sysfs-schemes: set damos->migrate_dest

 include/linux/damon.h    |  29 ++++-
 mm/damon/core.c          |   4 +
 mm/damon/sysfs-schemes.c | 253 ++++++++++++++++++++++++++++++++++++++-
 3 files changed, 282 insertions(+), 4 deletions(-)


base-commit: 78745efafbb93197e476717385616ed57ea2df22
-- 
2.39.5