Commit b696722d authored Jun 14, 2024 by Hyeongtak Ji Committed by Andrew Morton Jul 03, 2024

mm/damon/paddr: introduce DAMOS_MIGRATE_HOT action for promotion

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>

parent b51820eb

include/linux/damon.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -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,

mm/damon/paddr.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -486,6 +486,7 @@ static unsigned long damon_pa_apply_scheme(struct damon_ctx *ctx,
		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 damon_ctx *context,
		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:

mm/damon/sysfs-schemes.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -1458,6 +1458,7 @@ static const char * const damon_sysfs_damos_action_strs[] = {
		"nohugepage",
		"lru_prio",
		"lru_deprio",
		"migrate_hot",
		"migrate_cold",
		"stat",
		};