damon_nr_accesses_to_accesses_bp() actually converts a positive sample
count to the ratio.  Rename it to better describe what it really does
and not confusing for more general uses.

Also remove the obsolete comment about division-by-zero.  Commit
35d4a3cf70a8 ("mm/damon/ops-common: handle extreme intervals in
damon_hot_score()") modified damon_nr_samples_per_aggr() to always
return non-zero.  Hence no division-by-zero of the note can happen.

Signed-off-by: SJ Park <sj@kernel.org>
---
 mm/damon/core.c             | 17 +++++------------
 mm/damon/tests/core-kunit.h |  8 ++++----
 2 files changed, 9 insertions(+), 16 deletions(-)

diff --git a/mm/damon/core.c b/mm/damon/core.c
index ca530faaa4f83..718268df27fa7 100644
--- a/mm/damon/core.c
+++ b/mm/damon/core.c
@@ -883,25 +883,18 @@ static unsigned int damon_sample_bp_to_count(
 	return bp * damon_nr_samples_per_aggr(attrs) / 10000;
 }
 
-/*
- * Convert nr_accesses to access ratio in bp (per 10,000).
- *
- * Callers should ensure attrs.aggr_interval is not zero, like
- * damon_update_monitoring_results() does .  Otherwise, divide-by-zero would
- * happen.
- */
-static unsigned int damon_nr_accesses_to_accesses_bp(
-		unsigned int nr_accesses, struct damon_attrs *attrs)
+/* convert sample count to ratio in bp (per 10,000) */
+static unsigned int damon_sample_count_to_bp(
+		unsigned int count, struct damon_attrs *attrs)
 {
-	return mult_frac(nr_accesses, 10000, damon_nr_samples_per_aggr(attrs));
+	return mult_frac(count, 10000, damon_nr_samples_per_aggr(attrs));
 }
 
 static unsigned int damon_nr_accesses_for_new_attrs(unsigned int nr_accesses,
 		struct damon_attrs *old_attrs, struct damon_attrs *new_attrs)
 {
 	return damon_sample_bp_to_count(
-			damon_nr_accesses_to_accesses_bp(
-				nr_accesses, old_attrs),
+			damon_sample_count_to_bp(nr_accesses, old_attrs),
 			new_attrs);
 }
 
diff --git a/mm/damon/tests/core-kunit.h b/mm/damon/tests/core-kunit.h
index 0124f83b39b83..86eae3a590354 100644
--- a/mm/damon/tests/core-kunit.h
+++ b/mm/damon/tests/core-kunit.h
@@ -575,7 +575,7 @@ static void damon_test_set_regions(struct kunit *test)
 			}, 3);
 }
 
-static void damon_test_nr_accesses_to_accesses_bp(struct kunit *test)
+static void damon_test_sample_count_to_bp(struct kunit *test)
 {
 	struct damon_attrs attrs = {
 		.sample_interval = 10,
@@ -585,7 +585,7 @@ static void damon_test_nr_accesses_to_accesses_bp(struct kunit *test)
 	/*
 	 * In some cases such as 32bit architectures where UINT_MAX is
 	 * ULONG_MAX, attrs.aggr_interval becomes zero.  Calling
-	 * damon_nr_accesses_to_accesses_bp() in the case will cause
+	 * damon_sample_count_to_bp() in the case will cause
 	 * divide-by-zero.  Such case is prohibited in normal execution since
 	 * the caution is documented on the comment for the function, and
 	 * damon_update_monitoring_results() does the check.  Skip the test in
@@ -594,7 +594,7 @@ static void damon_test_nr_accesses_to_accesses_bp(struct kunit *test)
 	if (!attrs.aggr_interval)
 		kunit_skip(test, "aggr_interval is zero.");
 
-	KUNIT_EXPECT_EQ(test, damon_nr_accesses_to_accesses_bp(123, &attrs), 0);
+	KUNIT_EXPECT_EQ(test, damon_sample_count_to_bp(123, &attrs), 0);
 }
 
 static void damon_test_update_monitoring_result(struct kunit *test)
@@ -1572,7 +1572,7 @@ static struct kunit_case damon_test_cases[] = {
 	KUNIT_CASE(damon_test_split_above_half_progresses),
 	KUNIT_CASE(damon_test_ops_registration),
 	KUNIT_CASE(damon_test_set_regions),
-	KUNIT_CASE(damon_test_nr_accesses_to_accesses_bp),
+	KUNIT_CASE(damon_test_sample_count_to_bp),
 	KUNIT_CASE(damon_test_update_monitoring_result),
 	KUNIT_CASE(damon_test_set_attrs),
 	KUNIT_CASE(damon_test_mvsum),
-- 
2.47.3