+ mm-damon-core-test-add-a-unit-test-for-the-feedback-loop-algorithm.patch added to mm-unstable branch

+ mm-damon-core-test-add-a-unit-test-for-the-feedback-loop-algorithm.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm/damon/core-test: add a unit test for the feedback loop algorithm
has been added to the -mm mm-unstable branch.  Its filename is
     mm-damon-core-test-add-a-unit-test-for-the-feedback-loop-algorithm.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-damon-core-test-add-a-unit-test-for-the-feedback-loop-algorithm.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: SeongJae Park <sj@kernel.org>
Subject: mm/damon/core-test: add a unit test for the feedback loop algorithm
Date: Thu, 30 Nov 2023 02:36:48 +0000

Implement a simple kunit test for testing the behavior of the feedback
loop algorithm for the aim-oriented feedback-friven DAMOS aggressiveness
auto tuning.

Link: https://lkml.kernel.org/r/20231130023652.50284-6-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Brendan Higgins <brendanhiggins@google.com>
Cc: David Gow <davidgow@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/damon/core-test.h |   32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

--- a/mm/damon/core-test.h~mm-damon-core-test-add-a-unit-test-for-the-feedback-loop-algorithm
+++ a/mm/damon/core-test.h
@@ -446,6 +446,37 @@ static void damos_test_filter_out(struct
 	damos_free_filter(f);
 }
 
+static void damon_test_feed_loop_next_input(struct kunit *test)
+{
+	unsigned long last_input = 900000, current_score = 200;
+
+	/*
+	 * If current score is lower than the goal, which is always 10,000
+	 * (read the comment on damon_feed_loop_next_input()'s comment), next
+	 * input should be higher than the last input.
+	 */
+	KUNIT_EXPECT_GT(test,
+			damon_feed_loop_next_input(last_input, current_score),
+			last_input);
+
+	/*
+	 * If current score is higher than the goal, next input should be lower
+	 * than the last input.
+	 */
+	current_score = 250000000;
+	KUNIT_EXPECT_LT(test,
+			damon_feed_loop_next_input(last_input, current_score),
+			last_input);
+
+	/*
+	 * The next input depends on the distance between the current score and
+	 * the goal
+	 */
+	KUNIT_EXPECT_GT(test,
+			damon_feed_loop_next_input(last_input, 200),
+			damon_feed_loop_next_input(last_input, 2000));
+}
+
 static struct kunit_case damon_test_cases[] = {
 	KUNIT_CASE(damon_test_target),
 	KUNIT_CASE(damon_test_regions),
@@ -461,6 +492,7 @@ static struct kunit_case damon_test_case
 	KUNIT_CASE(damon_test_moving_sum),
 	KUNIT_CASE(damos_test_new_filter),
 	KUNIT_CASE(damos_test_filter_out),
+	KUNIT_CASE(damon_test_feed_loop_next_input),
 	{},
 };
 
_

Patches currently in -mm which might be from sj@kernel.org are

mm-damon-core-copy-nr_accesses-when-splitting-region.patch
mm-damon-sysfs-schemes-add-timeout-for-update_schemes_tried_regions.patch
mm-damon-core-test-test-damon_split_region_ats-access-rate-copying.patch
mm-damon-core-implement-goal-oriented-feedback-driven-quota-auto-tuning.patch
mm-damon-sysfs-schemes-implement-files-for-scheme-quota-goals-setup.patch
mm-damon-sysfs-schemes-commit-damos-quota-goals-user-input-to-damos.patch
mm-damon-sysfs-schemes-implement-a-command-for-scheme-quota-goals-only-commit.patch
mm-damon-core-test-add-a-unit-test-for-the-feedback-loop-algorithm.patch
selftests-damon-test-quota-goals-directory.patch
docs-mm-damon-design-document-damos-quota-auto-tuning.patch
docs-abi-damon-document-damos-quota-goals.patch
docs-admin-guide-mm-damon-usage-document-for-quota-goals.patch