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* [RFC PATCH v1.1 00/11] mm/damon: update, optimize, and clean up doc, tests, and code
@ 2026-06-25  5:07 SeongJae Park
  2026-06-25  5:07 ` [RFC PATCH v1.1 01/11] Docs/mm/damon/design: update for DAMOS_QUOTA_NODE_ELIGIBLE_MEM_BP SeongJae Park
                   ` (10 more replies)
  0 siblings, 11 replies; 12+ messages in thread
From: SeongJae Park @ 2026-06-25  5:07 UTC (permalink / raw)
  Cc: SeongJae Park, Liam R. Howlett, Andrew Morton, Brendan Higgins,
	David Gow, David Hildenbrand, Jonathan Corbet, Lorenzo Stoakes,
	Michal Hocko, Mike Rapoport, Shuah Khan, Shuah Khan,
	Suren Baghdasaryan, Vlastimil Babka, damon, kunit-dev, linux-doc,
	linux-kernel, linux-kselftest, linux-mm

Patches 1 and 2 update the design and ABI documents for recently added
DAMON features.  Patches 3-7 add or update more unit and self tests for
DAMON to cover recently changed or added functions and sysfs files.
Patch 8 optimizes damon_commit_target_regions() to skip unnecessary
adjacent ranges setup.  Patches 9-11 clean and fix up recently added
DAMON sysfs interface code for readability.

Changes from RFC
- RFC: https://lore.kernel.org/20260624142008.87180-1-sj@kernel.org
- Rebase directly to latest mm-new.

SeongJae Park (11):
  Docs/mm/damon/design: update for DAMOS_QUOTA_NODE_ELIGIBLE_MEM_BP
  Docs/ABI/damon: document probe files
  mm/damon/tests/core-kunit: test damon_rand()
  selftests/damon/sysfs.sh: test multiple probe dirs creation
  selftests/damon/sysfs.sh: test {core,ops}_filters/ directories
  selftests/damon/sysfs.sh: test dests dir
  selftests/damon/sysfs.sh: test all files in quota goal dir
  mm/damon/core: reduce range setup in damon_commit_target_regions()
  mm/damon/sysfs: split probe setup function out
  mm/damon/sysfs: split out filters setup function
  mm/damon/sysfs: fix typos in probe_{add,rm}_dirs: s/attr/probe/

 .../ABI/testing/sysfs-kernel-mm-damon         |  40 +++++++
 Documentation/mm/damon/design.rst             |   2 +
 mm/damon/core.c                               |  22 +++-
 mm/damon/sysfs.c                              | 102 ++++++++++--------
 mm/damon/tests/core-kunit.h                   |  21 ++++
 tools/testing/selftests/damon/sysfs.sh        |  70 +++++++++++-
 6 files changed, 206 insertions(+), 51 deletions(-)


base-commit: 09ff70563340c38d31012044b9c6c18f225f4fbf
-- 
2.47.3

^ permalink raw reply	[flat|nested] 12+ messages in thread

* [RFC PATCH v1.1 01/11] Docs/mm/damon/design: update for DAMOS_QUOTA_NODE_ELIGIBLE_MEM_BP
  2026-06-25  5:07 [RFC PATCH v1.1 00/11] mm/damon: update, optimize, and clean up doc, tests, and code SeongJae Park
@ 2026-06-25  5:07 ` SeongJae Park
  2026-06-25  5:07 ` [RFC PATCH v1.1 02/11] Docs/ABI/damon: document probe files SeongJae Park
                   ` (9 subsequent siblings)
  10 siblings, 0 replies; 12+ messages in thread
From: SeongJae Park @ 2026-06-25  5:07 UTC (permalink / raw)
  Cc: SeongJae Park, Liam R. Howlett, Andrew Morton, David Hildenbrand,
	Jonathan Corbet, Lorenzo Stoakes, Michal Hocko, Mike Rapoport,
	Shuah Khan, Suren Baghdasaryan, Vlastimil Babka, damon, linux-doc,
	linux-kernel, linux-mm

Commit 9138e27a3bc3 ("mm/damon: add node_eligible_mem_bp goal metric")
introduced DAMOS_QUOTA_NODE_ELIGIBLE_MEM_BP but forgot updating the
DAMON design document for that.  Update.

Signed-off-by: SeongJae Park <sj@kernel.org>
---
 Documentation/mm/damon/design.rst | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Documentation/mm/damon/design.rst b/Documentation/mm/damon/design.rst
index 2da7ca0d3d17a..1ed02f2280790 100644
--- a/Documentation/mm/damon/design.rst
+++ b/Documentation/mm/damon/design.rst
@@ -686,6 +686,8 @@ mechanism tries to make ``current_value`` of ``target_metric`` be same to
   (1/10,000).
 - ``inactive_mem_bp``: Inactive to active + inactive (LRU) memory size ratio in
   bp (1/10,000).
+- ``node_eligible_mem_bp``: Scheme target access pattern-eligible memory ratio
+  of a node in bp (1/10,000).
 
 ``nid`` is optionally required for only ``node_mem_used_bp``,
 ``node_mem_free_bp``, ``node_memcg_used_bp`` and ``node_memcg_free_bp`` to
-- 
2.47.3

^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [RFC PATCH v1.1 02/11] Docs/ABI/damon: document probe files
  2026-06-25  5:07 [RFC PATCH v1.1 00/11] mm/damon: update, optimize, and clean up doc, tests, and code SeongJae Park
  2026-06-25  5:07 ` [RFC PATCH v1.1 01/11] Docs/mm/damon/design: update for DAMOS_QUOTA_NODE_ELIGIBLE_MEM_BP SeongJae Park
@ 2026-06-25  5:07 ` SeongJae Park
  2026-06-25  5:07 ` [RFC PATCH v1.1 03/11] mm/damon/tests/core-kunit: test damon_rand() SeongJae Park
                   ` (8 subsequent siblings)
  10 siblings, 0 replies; 12+ messages in thread
From: SeongJae Park @ 2026-06-25  5:07 UTC (permalink / raw)
  Cc: SeongJae Park, Liam R. Howlett, Andrew Morton, David Hildenbrand,
	Lorenzo Stoakes, Michal Hocko, Mike Rapoport, Suren Baghdasaryan,
	Vlastimil Babka, damon, linux-kernel, linux-mm

DAMON ABI document is not updated for the DAMON probe sysfs files.
Update.

Signed-off-by: SeongJae Park <sj@kernel.org>
---
 .../ABI/testing/sysfs-kernel-mm-damon         | 40 +++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/Documentation/ABI/testing/sysfs-kernel-mm-damon b/Documentation/ABI/testing/sysfs-kernel-mm-damon
index b73e6bc28ea5f..2815f6bc05c18 100644
--- a/Documentation/ABI/testing/sysfs-kernel-mm-damon
+++ b/Documentation/ABI/testing/sysfs-kernel-mm-damon
@@ -157,6 +157,46 @@ Description:	Writing a value to this file sets the maximum number of
 		monitoring regions of the DAMON context as the value.  Reading
 		this file returns the value.
 
+What:		/sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/monitoring_attrs/probes/nr_probes
+Date:		May 2026
+Contact:	SeongJae Park <sj@kernel.org>
+Description:	Writing a number 'N' to this file creates the number of
+		directories for each DAMON probe named '0' to 'N-1' under the
+		probes/ directory.
+
+What:		/sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/monitoring_attrs/probes/<P>/filters/nr_filters
+Date:		May 2026
+Contact:	SeongJae Park <sj@kernel.org>
+Description:	Writing a number 'N' to this file creates the number of
+		directories for each DAMON probe filter named '0' to 'N-1'
+		under the filters/ directory.
+
+What:		/sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/monitoring_attrs/probes/<P>/filters/<F>/type
+Date:		May 2026
+Contact:	SeongJae Park <sj@kernel.org>
+Description:	Writing to and reading from this file sets and gets the type of
+		the memory of the interest.
+
+What:		/sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/monitoring_attrs/probes/<P>/filters/<F>/path
+Date:		May 2026
+Contact:	SeongJae Park <sj@kernel.org>
+Description:	If 'memmcg' is written to the 'type' file, writing to and
+		reading from this file sets and geets the path to the memory
+		cgroup of the interest.
+
+What:		/sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/monitoring_attrs/probes/<P>/filters/<F>/matching
+Date:		May 2026
+Contact:	SeongJae Park <sj@kernel.org>
+Description:	Writing 'Y' or 'N' to this file sets whether the filter is for
+		the memory of the 'type', or all except the 'type'.
+
+What:		/sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/monitoring_attrs/probes/<P>/filters/<F>/allow
+Date:		May 2026
+Contact:	SeongJae Park <sj@kernel.org>
+Description:	Writing 'Y' or 'N' to this file sets whether to allow or reject
+		hitting the probe for the memory that satisfies the 'type' and
+		the 'matching' of the directory.
+
 What:		/sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/targets/nr_targets
 Date:		Mar 2022
 Contact:	SeongJae Park <sj@kernel.org>
-- 
2.47.3

^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [RFC PATCH v1.1 03/11] mm/damon/tests/core-kunit: test damon_rand()
  2026-06-25  5:07 [RFC PATCH v1.1 00/11] mm/damon: update, optimize, and clean up doc, tests, and code SeongJae Park
  2026-06-25  5:07 ` [RFC PATCH v1.1 01/11] Docs/mm/damon/design: update for DAMOS_QUOTA_NODE_ELIGIBLE_MEM_BP SeongJae Park
  2026-06-25  5:07 ` [RFC PATCH v1.1 02/11] Docs/ABI/damon: document probe files SeongJae Park
@ 2026-06-25  5:07 ` SeongJae Park
  2026-06-25  5:07 ` [RFC PATCH v1.1 04/11] selftests/damon/sysfs.sh: test multiple probe dirs creation SeongJae Park
                   ` (7 subsequent siblings)
  10 siblings, 0 replies; 12+ messages in thread
From: SeongJae Park @ 2026-06-25  5:07 UTC (permalink / raw)
  Cc: SeongJae Park, Andrew Morton, Brendan Higgins, David Gow, damon,
	kunit-dev, linux-kernel, linux-kselftest, linux-mm

Commit 9012c4e647df ("mm/damon: replace damon_rand() with a per-ctx
lockless PRNG") optimized DAMON for better performance.  Add a kunit
test for ensuring the pseudo randomness quality.

Signed-off-by: SeongJae Park <sj@kernel.org>
---
 mm/damon/tests/core-kunit.h | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/mm/damon/tests/core-kunit.h b/mm/damon/tests/core-kunit.h
index 1cfb8c176b873..756f3b9e2ed3b 100644
--- a/mm/damon/tests/core-kunit.h
+++ b/mm/damon/tests/core-kunit.h
@@ -1460,6 +1460,26 @@ static void damon_test_is_last_region(struct kunit *test)
 	damon_free_target(t);
 }
 
+static void damon_test_rand(struct kunit *test)
+{
+	struct damon_ctx ctx;
+	int counts[10] = {};
+	int i;
+
+	prandom_seed_state(&ctx.rnd_state, get_random_u64());
+	for (i = 0; i < 10000; i++) {
+		unsigned long rnd = damon_rand(&ctx, 0, 10);
+
+		KUNIT_EXPECT_GE(test, rnd, 0);
+		KUNIT_EXPECT_LE(test, rnd, 9);
+		counts[rnd]++;
+	}
+	for (i = 0; i < 10; i++) {
+		KUNIT_EXPECT_GE(test, counts[i], 900);
+		KUNIT_EXPECT_LE(test, counts[i], 1100);
+	}
+}
+
 static struct kunit_case damon_test_cases[] = {
 	KUNIT_CASE(damon_test_target),
 	KUNIT_CASE(damon_test_regions),
@@ -1489,6 +1509,7 @@ static struct kunit_case damon_test_cases[] = {
 	KUNIT_CASE(damon_test_set_filters_default_reject),
 	KUNIT_CASE(damon_test_apply_min_nr_regions),
 	KUNIT_CASE(damon_test_is_last_region),
+	KUNIT_CASE(damon_test_rand),
 	{},
 };
 
-- 
2.47.3

^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [RFC PATCH v1.1 04/11] selftests/damon/sysfs.sh: test multiple probe dirs creation
  2026-06-25  5:07 [RFC PATCH v1.1 00/11] mm/damon: update, optimize, and clean up doc, tests, and code SeongJae Park
                   ` (2 preceding siblings ...)
  2026-06-25  5:07 ` [RFC PATCH v1.1 03/11] mm/damon/tests/core-kunit: test damon_rand() SeongJae Park
@ 2026-06-25  5:07 ` SeongJae Park
  2026-06-25  5:07 ` [RFC PATCH v1.1 05/11] selftests/damon/sysfs.sh: test {core,ops}_filters/ directories SeongJae Park
                   ` (6 subsequent siblings)
  10 siblings, 0 replies; 12+ messages in thread
From: SeongJae Park @ 2026-06-25  5:07 UTC (permalink / raw)
  Cc: SeongJae Park, Shuah Khan, damon, linux-kernel, linux-kselftest,
	linux-mm

DAMON sysfs essential file operations test (sysfs.sh) was extended to
test DAMON probes sysfs directory, by commit 14885da09b0f
("selftests/damon/sysfs.sh: test probes dir").  Unlike other DAMON sysfs
files, it is testing only a single directory case.  Extend it for
multiple directories.

Signed-off-by: SeongJae Park <sj@kernel.org>
---
 tools/testing/selftests/damon/sysfs.sh | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/tools/testing/selftests/damon/sysfs.sh b/tools/testing/selftests/damon/sysfs.sh
index 78f4badb5bebb..0f2ef462a6b6a 100755
--- a/tools/testing/selftests/damon/sysfs.sh
+++ b/tools/testing/selftests/damon/sysfs.sh
@@ -346,8 +346,13 @@ test_probes()
 	ensure_write_succ "$probes_dir/nr_probes" "1" "valid input"
 	test_probe "$probes_dir/0"
 
+	ensure_write_succ "$probes_dir/nr_probes" "2" "valid input"
+	test_probe "$probes_dir/0"
+	test_probe "$probes_dir/1"
+
 	ensure_write_succ "$probes_dir/nr_probes" "0" "valid input"
 	ensure_dir "$probes_dir/0" "not_exist"
+	ensure_dir "$probes_dir/1" "not_exist"
 }
 
 test_monitoring_attrs()
-- 
2.47.3

^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [RFC PATCH v1.1 05/11] selftests/damon/sysfs.sh: test {core,ops}_filters/ directories
  2026-06-25  5:07 [RFC PATCH v1.1 00/11] mm/damon: update, optimize, and clean up doc, tests, and code SeongJae Park
                   ` (3 preceding siblings ...)
  2026-06-25  5:07 ` [RFC PATCH v1.1 04/11] selftests/damon/sysfs.sh: test multiple probe dirs creation SeongJae Park
@ 2026-06-25  5:07 ` SeongJae Park
  2026-06-25  5:07 ` [RFC PATCH v1.1 06/11] selftests/damon/sysfs.sh: test dests dir SeongJae Park
                   ` (5 subsequent siblings)
  10 siblings, 0 replies; 12+ messages in thread
From: SeongJae Park @ 2026-06-25  5:07 UTC (permalink / raw)
  Cc: SeongJae Park, Shuah Khan, damon, linux-kernel, linux-kselftest,
	linux-mm

DAMON sysfs interface essential file operations test (sysf.sh) is not
testing DAMOS {core,ops}_filters directories.  Add the tests.

Signed-off-by: SeongJae Park <sj@kernel.org>
---
 tools/testing/selftests/damon/sysfs.sh | 28 ++++++++++++++++++++++----
 1 file changed, 24 insertions(+), 4 deletions(-)

diff --git a/tools/testing/selftests/damon/sysfs.sh b/tools/testing/selftests/damon/sysfs.sh
index 0f2ef462a6b6a..07a33995be852 100755
--- a/tools/testing/selftests/damon/sysfs.sh
+++ b/tools/testing/selftests/damon/sysfs.sh
@@ -103,10 +103,28 @@ test_filter()
 {
 	filter_dir=$1
 	ensure_file "$filter_dir/type" "exist" "600"
-	ensure_write_succ "$filter_dir/type" "anon" "valid input"
-	ensure_write_succ "$filter_dir/type" "memcg" "valid input"
-	ensure_write_succ "$filter_dir/type" "addr" "valid input"
-	ensure_write_succ "$filter_dir/type" "target" "valid input"
+
+	local dir_name=$(basename "$(dirname "$filter_dir")")
+	if  [ "$dir_name" = "filters" ] || [ "$dir_name" = "ops_filters" ]
+	then
+		ensure_write_succ "$filter_dir/type" "anon" "valid input"
+		ensure_write_succ "$filter_dir/type" "memcg" "valid input"
+	fi
+	if  [ "$dir_name" = "filters" ] || [ "$dir_name" = "core_filters" ]
+	then
+		ensure_write_succ "$filter_dir/type" "addr" "valid input"
+		ensure_write_succ "$filter_dir/type" "target" "valid input"
+	fi
+	if [ "$dir_name" = "core_filters" ]
+	then
+		ensure_write_fail "$filter_dir/type" "anon" "ops type"
+		ensure_write_fail "$filter_dir/type" "memcg" "ops type"
+	fi
+	if [ "$dir_name"  = "ops_filters" ]
+	then
+		ensure_write_fail "$filter_dir/type" "addr" "core type"
+		ensure_write_fail "$filter_dir/type" "target" "core type"
+	fi
 	ensure_write_fail "$filter_dir/type" "foo" "invalid input"
 	ensure_file "$filter_dir/matching" "exist" "600"
 	ensure_file "$filter_dir/memcg_path" "exist" "600"
@@ -208,6 +226,8 @@ test_scheme()
 	test_quotas "$scheme_dir/quotas"
 	test_watermarks "$scheme_dir/watermarks"
 	test_filters "$scheme_dir/filters"
+	test_filters "$scheme_dir/core_filters"
+	test_filters "$scheme_dir/ops_filters"
 	test_stats "$scheme_dir/stats"
 	test_tried_regions "$scheme_dir/tried_regions"
 }
-- 
2.47.3

^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [RFC PATCH v1.1 06/11] selftests/damon/sysfs.sh: test dests dir
  2026-06-25  5:07 [RFC PATCH v1.1 00/11] mm/damon: update, optimize, and clean up doc, tests, and code SeongJae Park
                   ` (4 preceding siblings ...)
  2026-06-25  5:07 ` [RFC PATCH v1.1 05/11] selftests/damon/sysfs.sh: test {core,ops}_filters/ directories SeongJae Park
@ 2026-06-25  5:07 ` SeongJae Park
  2026-06-25  5:07 ` [RFC PATCH v1.1 07/11] selftests/damon/sysfs.sh: test all files in quota goal dir SeongJae Park
                   ` (4 subsequent siblings)
  10 siblings, 0 replies; 12+ messages in thread
From: SeongJae Park @ 2026-06-25  5:07 UTC (permalink / raw)
  Cc: SeongJae Park, Shuah Khan, damon, linux-kernel, linux-kselftest,
	linux-mm

DAMON selftest interface essential file operations test (sysfs.sh) is
not testing DAMOS dests/ directory.  Add the test.

Signed-off-by: SeongJae Park <sj@kernel.org>
---
 tools/testing/selftests/damon/sysfs.sh | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/tools/testing/selftests/damon/sysfs.sh b/tools/testing/selftests/damon/sysfs.sh
index 07a33995be852..ffa8413b5ab3d 100755
--- a/tools/testing/selftests/damon/sysfs.sh
+++ b/tools/testing/selftests/damon/sysfs.sh
@@ -99,6 +99,29 @@ test_stats()
 	done
 }
 
+test_dest()
+{
+	dest_dir=$1
+	ensure_file "$dest_dir/id" "exist"
+	ensure_file "$dest_dir/weight" "exist"
+}
+
+test_dests()
+{
+	dests_dir=$1
+	ensure_file "$dests_dir/nr_dests" "exist" "600"
+	ensure_write_succ "$dests_dir/nr_dests" "1" "valid input"
+	test_dest "$dests_dir/0"
+
+	ensure_write_succ "$dests_dir/nr_dests" "2" "valid input"
+	test_dest "$dests_dir/0"
+	test_dest "$dests_dir/1"
+
+	ensure_write_succ "$dests_dir/nr_dests" "0" "valid input"
+	ensure_dir "$dests_dir/0" "not_exist"
+	ensure_dir "$dests_dir/1" "not_exist"
+}
+
 test_filter()
 {
 	filter_dir=$1
-- 
2.47.3

^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [RFC PATCH v1.1 07/11] selftests/damon/sysfs.sh: test all files in quota goal dir
  2026-06-25  5:07 [RFC PATCH v1.1 00/11] mm/damon: update, optimize, and clean up doc, tests, and code SeongJae Park
                   ` (5 preceding siblings ...)
  2026-06-25  5:07 ` [RFC PATCH v1.1 06/11] selftests/damon/sysfs.sh: test dests dir SeongJae Park
@ 2026-06-25  5:07 ` SeongJae Park
  2026-06-25  5:07 ` [RFC PATCH v1.1 08/11] mm/damon/core: reduce range setup in damon_commit_target_regions() SeongJae Park
                   ` (3 subsequent siblings)
  10 siblings, 0 replies; 12+ messages in thread
From: SeongJae Park @ 2026-06-25  5:07 UTC (permalink / raw)
  Cc: SeongJae Park, Shuah Khan, damon, linux-kernel, linux-kselftest,
	linux-mm

DAMON sysfs interface for DAMOS quota has quite extended since its
initial introduction.  The test case for that in DAMON sysfs interface
essential file operations test (sysfs.sh) has not accordingly extended,
though.  Extend the test case to test all existing files.

Signed-off-by: SeongJae Park <sj@kernel.org>
---
 tools/testing/selftests/damon/sysfs.sh | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/tools/testing/selftests/damon/sysfs.sh b/tools/testing/selftests/damon/sysfs.sh
index ffa8413b5ab3d..15fb9df928818 100755
--- a/tools/testing/selftests/damon/sysfs.sh
+++ b/tools/testing/selftests/damon/sysfs.sh
@@ -199,6 +199,20 @@ test_goal()
 	ensure_dir "$goal_dir" "exist"
 	ensure_file "$goal_dir/target_value" "exist" "600"
 	ensure_file "$goal_dir/current_value" "exist" "600"
+	ensure_file "$goal_dir/target_metric" "exist" "600"
+	local fpath="$goal_dir/target_metric"
+	ensure_write_succ "$fpath" "user_input" "valid input"
+	ensure_write_succ "$fpath" "some_mem_psi_us" "valid input"
+	ensure_write_succ "$fpath" "node_mem_used_bp" "valid input"
+	ensure_write_succ "$fpath" "node_mem_free_bp" "valid input"
+	ensure_write_succ "$fpath" "node_memcg_used_bp" "valid input"
+	ensure_write_succ "$fpath" "node_memcg_free_bp" "valid input"
+	ensure_write_succ "$fpath" "active_mem_bp" "valid input"
+	ensure_write_succ "$fpath" "inactive_mem_bp" "valid input"
+	ensure_write_succ "$fpath" "node_eligible_mem_bp" "valid input"
+	ensure_write_fail "$fpath" "foo" "invalid input"
+	ensure_file "$goal_dir/nid" "exist" "600"
+	ensure_file "$goal_dir/path" "exist" "600"
 }
 
 test_goals()
-- 
2.47.3

^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [RFC PATCH v1.1 08/11] mm/damon/core: reduce range setup in damon_commit_target_regions()
  2026-06-25  5:07 [RFC PATCH v1.1 00/11] mm/damon: update, optimize, and clean up doc, tests, and code SeongJae Park
                   ` (6 preceding siblings ...)
  2026-06-25  5:07 ` [RFC PATCH v1.1 07/11] selftests/damon/sysfs.sh: test all files in quota goal dir SeongJae Park
@ 2026-06-25  5:07 ` SeongJae Park
  2026-06-25  5:07 ` [RFC PATCH v1.1 09/11] mm/damon/sysfs: split probe setup function out SeongJae Park
                   ` (2 subsequent siblings)
  10 siblings, 0 replies; 12+ messages in thread
From: SeongJae Park @ 2026-06-25  5:07 UTC (permalink / raw)
  Cc: SeongJae Park, Andrew Morton, damon, linux-kernel, linux-mm

damon_commit_target_regions() calls damon_set_regions() for updating the
destination target's monitoring target region boundaries.  It sets the
boundaries same to source target's monitoring regions, even if they are
adjacent.  Meanwhile, damon_set_region() sets the destination target
regions exactly the same to the source, only when the target regions are
empty.  When there are existing target regions, only a few regions are
expanded or shrunk to fit on only the boundaries for disjoint regions in
the source.  Hence the adjacent source ranges mean nothing in common
cases.  When there are many regions, such adjacent range setup is only a
waste of time and space.  We recently found [1] it is actually causing
memory overhead.  Setup the ranges for only distinct ranges.

[1] https://lore.kernel.org/20260603112306.58490-1-akinobu.mita@gmail.com

Signed-off-by: SeongJae Park <sj@kernel.org>
---
 mm/damon/core.c | 22 +++++++++++++++++-----
 1 file changed, 17 insertions(+), 5 deletions(-)

diff --git a/mm/damon/core.c b/mm/damon/core.c
index 7e4b9affc5b06..ce5294cb1b4f3 100644
--- a/mm/damon/core.c
+++ b/mm/damon/core.c
@@ -1349,21 +1349,33 @@ static struct damon_target *damon_nth_target(int n, struct damon_ctx *ctx)
 static int damon_commit_target_regions(struct damon_target *dst,
 		struct damon_target *src, unsigned long src_min_region_sz)
 {
-	struct damon_region *src_region;
+	struct damon_region *src_region, *prev = NULL;
 	struct damon_addr_range *ranges;
 	int i = 0, err;
 
-	damon_for_each_region(src_region, src)
-		i++;
+	damon_for_each_region(src_region, src) {
+		if (!prev || prev->ar.end != src_region->ar.start)
+			i++;
+		prev = src_region;
+	}
 	if (!i)
 		return 0;
 
 	ranges = kmalloc_objs(*ranges, i, GFP_KERNEL | __GFP_NOWARN);
 	if (!ranges)
 		return -ENOMEM;
+	prev = NULL;
 	i = 0;
-	damon_for_each_region(src_region, src)
-		ranges[i++] = src_region->ar;
+	damon_for_each_region(src_region, src) {
+		if (!prev) {
+			ranges[i].start = src_region->ar.start;
+		} else if (prev->ar.end != src_region->ar.start) {
+			ranges[i++].end = prev->ar.end;
+			ranges[i].start = src_region->ar.start;
+		}
+		prev = src_region;
+	}
+	ranges[i++].end = damon_last_region(src)->ar.end;
 	err = damon_set_regions(dst, ranges, i, src_min_region_sz);
 	kfree(ranges);
 	return err;
-- 
2.47.3

^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [RFC PATCH v1.1 09/11] mm/damon/sysfs: split probe setup function out
  2026-06-25  5:07 [RFC PATCH v1.1 00/11] mm/damon: update, optimize, and clean up doc, tests, and code SeongJae Park
                   ` (7 preceding siblings ...)
  2026-06-25  5:07 ` [RFC PATCH v1.1 08/11] mm/damon/core: reduce range setup in damon_commit_target_regions() SeongJae Park
@ 2026-06-25  5:07 ` SeongJae Park
  2026-06-25  5:07 ` [RFC PATCH v1.1 10/11] mm/damon/sysfs: split out filters setup function SeongJae Park
  2026-06-25  5:07 ` [RFC PATCH v1.1 11/11] mm/damon/sysfs: fix typos in probe_{add,rm}_dirs: s/attr/probe/ SeongJae Park
  10 siblings, 0 replies; 12+ messages in thread
From: SeongJae Park @ 2026-06-25  5:07 UTC (permalink / raw)
  Cc: SeongJae Park, Andrew Morton, damon, linux-kernel, linux-mm

damon_sysfs_set_probes() function is relatively long.  It has two nested
loop for setting two nested entities, namely probe and filter.  Split
out the probe level setup for readability.

Signed-off-by: SeongJae Park <sj@kernel.org>
---
 mm/damon/sysfs.c | 80 ++++++++++++++++++++++++++++--------------------
 1 file changed, 46 insertions(+), 34 deletions(-)

diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c
index 2e95e3bac774d..982d824f63c21 100644
--- a/mm/damon/sysfs.c
+++ b/mm/damon/sysfs.c
@@ -1899,47 +1899,59 @@ static int damon_sysfs_set_attrs(struct damon_ctx *ctx,
 	return damon_set_attrs(ctx, &attrs);
 }
 
-static int damon_sysfs_set_probes(struct damon_ctx *ctx,
-		struct damon_sysfs_probes *sys_probes)
+static int damon_sysfs_set_probe(struct damon_probe *probe,
+		struct damon_sysfs_probe *sys_probe)
 {
+	struct damon_sysfs_filters *sys_filters;
 	int i;
 
-	for (i = 0; i < sys_probes->nr; i++) {
-		struct damon_sysfs_filters *sys_filters =
-			sys_probes->probes_arr[i]->filters;
-		struct damon_probe *c;
-		int j;
+	sys_filters = sys_probe->filters;
+	if (!sys_filters)
+		return 0;
 
-		if (!sys_filters)
-			continue;
-		c = damon_new_probe();
-		if (!c)
+	for (i = 0; i < sys_filters->nr; i++) {
+		struct damon_sysfs_filter *sys_filter =
+			sys_filters->filters_arr[i];
+		struct damon_filter *filter;
+
+		filter = damon_new_filter(sys_filter->type,
+				sys_filter->matching,
+				sys_filter->allow);
+		if (!filter)
 			return -ENOMEM;
-		damon_add_probe(ctx, c);
-
-		for (j = 0; j < sys_filters->nr; j++) {
-			struct damon_sysfs_filter *sys_filter =
-				sys_filters->filters_arr[j];
-			struct damon_filter *filter;
-
-			filter = damon_new_filter(sys_filter->type,
-					sys_filter->matching,
-					sys_filter->allow);
-			if (!filter)
-				return -ENOMEM;
-			if (filter->type == DAMON_FILTER_TYPE_MEMCG) {
-				int err;
-
-				err = damon_sysfs_memcg_path_to_id(
-						sys_filter->path,
-						&filter->memcg_id);
-				if (err) {
-					damon_destroy_filter(filter);
-					return err;
-				}
+		if (filter->type == DAMON_FILTER_TYPE_MEMCG) {
+			int err;
+
+			err = damon_sysfs_memcg_path_to_id(
+					sys_filter->path,
+					&filter->memcg_id);
+			if (err) {
+				damon_destroy_filter(filter);
+				return err;
 			}
-			damon_add_filter(c, filter);
 		}
+		damon_add_filter(probe, filter);
+	}
+	return 0;
+}
+
+static int damon_sysfs_set_probes(struct damon_ctx *ctx,
+		struct damon_sysfs_probes *sys_probes)
+{
+	int i, err;
+
+	for (i = 0; i < sys_probes->nr; i++) {
+		struct damon_sysfs_probe *sys_probe;
+		struct damon_probe *p;
+
+		p = damon_new_probe();
+		if (!p)
+			return -ENOMEM;
+		damon_add_probe(ctx, p);
+		sys_probe = sys_probes->probes_arr[i];
+		err = damon_sysfs_set_probe(p, sys_probe);
+		if (err)
+			return err;
 	}
 	return 0;
 }
-- 
2.47.3

^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [RFC PATCH v1.1 10/11] mm/damon/sysfs: split out filters setup function
  2026-06-25  5:07 [RFC PATCH v1.1 00/11] mm/damon: update, optimize, and clean up doc, tests, and code SeongJae Park
                   ` (8 preceding siblings ...)
  2026-06-25  5:07 ` [RFC PATCH v1.1 09/11] mm/damon/sysfs: split probe setup function out SeongJae Park
@ 2026-06-25  5:07 ` SeongJae Park
  2026-06-25  5:07 ` [RFC PATCH v1.1 11/11] mm/damon/sysfs: fix typos in probe_{add,rm}_dirs: s/attr/probe/ SeongJae Park
  10 siblings, 0 replies; 12+ messages in thread
From: SeongJae Park @ 2026-06-25  5:07 UTC (permalink / raw)
  Cc: SeongJae Park, Andrew Morton, damon, linux-kernel, linux-mm

damon_sysfs_set_probe() is doing not only probe setup but also filters
setup.  Split out filters setup for readability.

Signed-off-by: SeongJae Park <sj@kernel.org>
---
 mm/damon/sysfs.c | 20 +++++++++++++-------
 1 file changed, 13 insertions(+), 7 deletions(-)

diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c
index 982d824f63c21..f3bb146b204df 100644
--- a/mm/damon/sysfs.c
+++ b/mm/damon/sysfs.c
@@ -1899,16 +1899,11 @@ static int damon_sysfs_set_attrs(struct damon_ctx *ctx,
 	return damon_set_attrs(ctx, &attrs);
 }
 
-static int damon_sysfs_set_probe(struct damon_probe *probe,
-		struct damon_sysfs_probe *sys_probe)
+static int damon_sysfs_set_filters(struct damon_probe *probe,
+		struct damon_sysfs_filters *sys_filters)
 {
-	struct damon_sysfs_filters *sys_filters;
 	int i;
 
-	sys_filters = sys_probe->filters;
-	if (!sys_filters)
-		return 0;
-
 	for (i = 0; i < sys_filters->nr; i++) {
 		struct damon_sysfs_filter *sys_filter =
 			sys_filters->filters_arr[i];
@@ -1935,6 +1930,17 @@ static int damon_sysfs_set_probe(struct damon_probe *probe,
 	return 0;
 }
 
+static int damon_sysfs_set_probe(struct damon_probe *probe,
+		struct damon_sysfs_probe *sys_probe)
+{
+	struct damon_sysfs_filters *sys_filters;
+
+	sys_filters = sys_probe->filters;
+	if (!sys_filters)
+		return 0;
+	return damon_sysfs_set_filters(probe, sys_filters);
+}
+
 static int damon_sysfs_set_probes(struct damon_ctx *ctx,
 		struct damon_sysfs_probes *sys_probes)
 {
-- 
2.47.3

^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [RFC PATCH v1.1 11/11] mm/damon/sysfs: fix typos in probe_{add,rm}_dirs: s/attr/probe/
  2026-06-25  5:07 [RFC PATCH v1.1 00/11] mm/damon: update, optimize, and clean up doc, tests, and code SeongJae Park
                   ` (9 preceding siblings ...)
  2026-06-25  5:07 ` [RFC PATCH v1.1 10/11] mm/damon/sysfs: split out filters setup function SeongJae Park
@ 2026-06-25  5:07 ` SeongJae Park
  10 siblings, 0 replies; 12+ messages in thread
From: SeongJae Park @ 2026-06-25  5:07 UTC (permalink / raw)
  Cc: SeongJae Park, Andrew Morton, damon, linux-kernel, linux-mm

damon_sysfs_probe_{add,rm}_dirs names a variable for damon_sysf_probe
as 'attr'.  Probably a trivial copy-pasta error, but it makes the code
not pleasant to read.  Fix those.

Signed-off-by: SeongJae Park <sj@kernel.org>
---
 mm/damon/sysfs.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c
index f3bb146b204df..36d71f1675426 100644
--- a/mm/damon/sysfs.c
+++ b/mm/damon/sysfs.c
@@ -1068,7 +1068,7 @@ static struct damon_sysfs_probe *damon_sysfs_probe_alloc(void)
 	return kzalloc_obj(struct damon_sysfs_probe);
 }
 
-static int damon_sysfs_probe_add_dirs(struct damon_sysfs_probe *attr)
+static int damon_sysfs_probe_add_dirs(struct damon_sysfs_probe *probe)
 {
 	struct damon_sysfs_filters *filters;
 	int err;
@@ -1076,22 +1076,22 @@ static int damon_sysfs_probe_add_dirs(struct damon_sysfs_probe *attr)
 	filters = damon_sysfs_filters_alloc();
 	if (!filters)
 		return -ENOMEM;
-	attr->filters = filters;
+	probe->filters = filters;
 
 	err = kobject_init_and_add(&filters->kobj, &damon_sysfs_filters_ktype,
-			&attr->kobj, "filters");
+			&probe->kobj, "filters");
 	if (err) {
 		kobject_put(&filters->kobj);
-		attr->filters = NULL;
+		probe->filters = NULL;
 	}
 	return err;
 }
 
-static void damon_sysfs_probe_rm_dirs(struct damon_sysfs_probe *attr)
+static void damon_sysfs_probe_rm_dirs(struct damon_sysfs_probe *probe)
 {
-	if (attr->filters) {
-		damon_sysfs_filters_rm_dirs(attr->filters);
-		kobject_put(&attr->filters->kobj);
+	if (probe->filters) {
+		damon_sysfs_filters_rm_dirs(probe->filters);
+		kobject_put(&probe->filters->kobj);
 	}
 }
 
-- 
2.47.3

^ permalink raw reply related	[flat|nested] 12+ messages in thread

end of thread, other threads:[~2026-06-25  5:08 UTC | newest]

Thread overview: 12+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2026-06-25  5:07 [RFC PATCH v1.1 00/11] mm/damon: update, optimize, and clean up doc, tests, and code SeongJae Park
2026-06-25  5:07 ` [RFC PATCH v1.1 01/11] Docs/mm/damon/design: update for DAMOS_QUOTA_NODE_ELIGIBLE_MEM_BP SeongJae Park
2026-06-25  5:07 ` [RFC PATCH v1.1 02/11] Docs/ABI/damon: document probe files SeongJae Park
2026-06-25  5:07 ` [RFC PATCH v1.1 03/11] mm/damon/tests/core-kunit: test damon_rand() SeongJae Park
2026-06-25  5:07 ` [RFC PATCH v1.1 04/11] selftests/damon/sysfs.sh: test multiple probe dirs creation SeongJae Park
2026-06-25  5:07 ` [RFC PATCH v1.1 05/11] selftests/damon/sysfs.sh: test {core,ops}_filters/ directories SeongJae Park
2026-06-25  5:07 ` [RFC PATCH v1.1 06/11] selftests/damon/sysfs.sh: test dests dir SeongJae Park
2026-06-25  5:07 ` [RFC PATCH v1.1 07/11] selftests/damon/sysfs.sh: test all files in quota goal dir SeongJae Park
2026-06-25  5:07 ` [RFC PATCH v1.1 08/11] mm/damon/core: reduce range setup in damon_commit_target_regions() SeongJae Park
2026-06-25  5:07 ` [RFC PATCH v1.1 09/11] mm/damon/sysfs: split probe setup function out SeongJae Park
2026-06-25  5:07 ` [RFC PATCH v1.1 10/11] mm/damon/sysfs: split out filters setup function SeongJae Park
2026-06-25  5:07 ` [RFC PATCH v1.1 11/11] mm/damon/sysfs: fix typos in probe_{add,rm}_dirs: s/attr/probe/ SeongJae Park

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