+ mm-damon-paddr-introduce-damos_migrate_hot-action-for-promotion.patch added to mm-unstable branch

+ mm-damon-paddr-introduce-damos_migrate_hot-action-for-promotion.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm/damon/paddr: introduce DAMOS_MIGRATE_HOT action for promotion
has been added to the -mm mm-unstable branch.  Its filename is
     mm-damon-paddr-introduce-damos_migrate_hot-action-for-promotion.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-damon-paddr-introduce-damos_migrate_hot-action-for-promotion.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Hyeongtak Ji <hyeongtak.ji@sk.com>
Subject: mm/damon/paddr: introduce DAMOS_MIGRATE_HOT action for promotion
Date: Fri, 14 Jun 2024 12:00:08 +0900

This patch introduces DAMOS_MIGRATE_HOT action, which is similar to
DAMOS_MIGRATE_COLD, but proritizes hot pages.

It migrates pages inside the given region to the 'target_nid' NUMA node
in the sysfs.

Here is one of the example usage of this 'migrate_hot' action.

  $ cd /sys/kernel/mm/damon/admin/kdamonds/<N>
  $ cat contexts/<N>/schemes/<N>/action
  migrate_hot
  $ echo 0 > contexts/<N>/schemes/<N>/target_nid
  $ echo commit > state
  $ numactl -p 2 ./hot_cold 500M 600M &
  $ numastat -c -p hot_cold

  Per-node process memory usage (in MBs)
  PID             Node 0 Node 1 Node 2 Total
  --------------  ------ ------ ------ -----
  701 (hot_cold)     501      0    601  1101

Link: https://lkml.kernel.org/r/20240614030010.751-7-honggyu.kim@sk.com
Signed-off-by: Hyeongtak Ji <hyeongtak.ji@sk.com>
Signed-off-by: Honggyu Kim <honggyu.kim@sk.com>
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Gregory Price <gregory.price@memverge.com>
Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Rakie Kim <rakie.kim@sk.com>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/damon.h    |    2 ++
 mm/damon/paddr.c         |    3 +++
 mm/damon/sysfs-schemes.c |    1 +
 3 files changed, 6 insertions(+)

--- a/include/linux/damon.h~mm-damon-paddr-introduce-damos_migrate_hot-action-for-promotion
+++ a/include/linux/damon.h
@@ -105,6 +105,7 @@ struct damon_target {
  * @DAMOS_NOHUGEPAGE:	Call ``madvise()`` for the region with MADV_NOHUGEPAGE.
  * @DAMOS_LRU_PRIO:	Prioritize the region on its LRU lists.
  * @DAMOS_LRU_DEPRIO:	Deprioritize the region on its LRU lists.
+ * @DAMOS_MIGRATE_HOT:  Migrate the regions prioritizing warmer regions.
  * @DAMOS_MIGRATE_COLD:	Migrate the regions prioritizing colder regions.
  * @DAMOS_STAT:		Do nothing but count the stat.
  * @NR_DAMOS_ACTIONS:	Total number of DAMOS actions
@@ -123,6 +124,7 @@ enum damos_action {
 	DAMOS_NOHUGEPAGE,
 	DAMOS_LRU_PRIO,
 	DAMOS_LRU_DEPRIO,
+	DAMOS_MIGRATE_HOT,
 	DAMOS_MIGRATE_COLD,
 	DAMOS_STAT,		/* Do nothing but only record the stat */
 	NR_DAMOS_ACTIONS,
--- a/mm/damon/paddr.c~mm-damon-paddr-introduce-damos_migrate_hot-action-for-promotion
+++ a/mm/damon/paddr.c
@@ -486,6 +486,7 @@ static unsigned long damon_pa_apply_sche
 		return damon_pa_mark_accessed(r, scheme);
 	case DAMOS_LRU_DEPRIO:
 		return damon_pa_deactivate_pages(r, scheme);
+	case DAMOS_MIGRATE_HOT:
 	case DAMOS_MIGRATE_COLD:
 		return damon_pa_migrate(r, scheme);
 	case DAMOS_STAT:
@@ -508,6 +509,8 @@ static int damon_pa_scheme_score(struct
 		return damon_hot_score(context, r, scheme);
 	case DAMOS_LRU_DEPRIO:
 		return damon_cold_score(context, r, scheme);
+	case DAMOS_MIGRATE_HOT:
+		return damon_hot_score(context, r, scheme);
 	case DAMOS_MIGRATE_COLD:
 		return damon_cold_score(context, r, scheme);
 	default:
--- a/mm/damon/sysfs-schemes.c~mm-damon-paddr-introduce-damos_migrate_hot-action-for-promotion
+++ a/mm/damon/sysfs-schemes.c
@@ -1458,6 +1458,7 @@ static const char * const damon_sysfs_da
 	"nohugepage",
 	"lru_prio",
 	"lru_deprio",
+	"migrate_hot",
 	"migrate_cold",
 	"stat",
 };
_

Patches currently in -mm which might be from hyeongtak.ji@sk.com are

mm-damon-sysfs-schemes-add-target_nid-on-sysfs-schemes.patch
mm-damon-paddr-introduce-damos_migrate_hot-action-for-promotion.patch