linux-kernel - [RFC PATCH v2 03/10] mm/damon/core: support damos

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Message-Id: <20241227210819.63776-4-sj@kernel.org>
Date: Fri, 27 Dec 2024 13:08:12 -0800
From: SeongJae Park <sj@...nel.org>
To: 
Cc: SeongJae Park <sj@...nel.org>,
	Andrew Morton <akpm@...ux-foundation.org>,
	damon@...ts.linux.dev,
	kernel-team@...a.com,
	linux-kernel@...r.kernel.org,
	linux-mm@...ck.org
Subject: [RFC PATCH v2 03/10] mm/damon/core: support damos_filter->pass

DAMON core logic is ignoring damos_filter->pass by assuming the value
will be false.  Respect it by dropping the assumption and reading the
field when making the decision to whether filter out or in a region.

Note that DAMOS action can be applied to any memory if no filter is
installed, and DAMOS filters work only for memory that satisfies the
'type' and 'matching'.  Hence installing pass filters without any block
filter after them makes no filter-behavioral change.

Signed-off-by: SeongJae Park <sj@...nel.org>
---
 mm/damon/core.c             |  6 +++---
 mm/damon/tests/core-kunit.h | 10 +++++-----
 2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/mm/damon/core.c b/mm/damon/core.c
index e54bd19d6f06..71db2c754e6d 100644
--- a/mm/damon/core.c
+++ b/mm/damon/core.c
@@ -1374,7 +1374,7 @@ static void damos_update_stat(struct damos *s,
 	s->stat.sz_ops_filter_passed += sz_ops_filter_passed;
 }
 
-static bool __damos_filter_out(struct damon_ctx *ctx, struct damon_target *t,
+static bool damos_filter_match(struct damon_ctx *ctx, struct damon_target *t,
 		struct damon_region *r, struct damos_filter *filter)
 {
 	bool matched = false;
@@ -1428,8 +1428,8 @@ static bool damos_filter_out(struct damon_ctx *ctx, struct damon_target *t,
 	struct damos_filter *filter;
 
 	damos_for_each_filter(filter, s) {
-		if (__damos_filter_out(ctx, t, r, filter))
-			return true;
+		if (damos_filter_match(ctx, t, r, filter))
+			return !filter->pass;
 	}
 	return false;
 }
diff --git a/mm/damon/tests/core-kunit.h b/mm/damon/tests/core-kunit.h
index cf22e09a3507..8f58d3424c21 100644
--- a/mm/damon/tests/core-kunit.h
+++ b/mm/damon/tests/core-kunit.h
@@ -434,25 +434,25 @@ static void damos_test_filter_out(struct kunit *test)
 	damon_add_region(r, t);
 
 	/* region in the range */
-	KUNIT_EXPECT_TRUE(test, __damos_filter_out(NULL, t, r, f));
+	KUNIT_EXPECT_TRUE(test, damos_filter_match(NULL, t, r, f));
 	KUNIT_EXPECT_EQ(test, damon_nr_regions(t), 1);
 
 	/* region before the range */
 	r->ar.start = DAMON_MIN_REGION * 1;
 	r->ar.end = DAMON_MIN_REGION * 2;
-	KUNIT_EXPECT_FALSE(test, __damos_filter_out(NULL, t, r, f));
+	KUNIT_EXPECT_FALSE(test, damos_filter_match(NULL, t, r, f));
 	KUNIT_EXPECT_EQ(test, damon_nr_regions(t), 1);
 
 	/* region after the range */
 	r->ar.start = DAMON_MIN_REGION * 6;
 	r->ar.end = DAMON_MIN_REGION * 8;
-	KUNIT_EXPECT_FALSE(test, __damos_filter_out(NULL, t, r, f));
+	KUNIT_EXPECT_FALSE(test, damos_filter_match(NULL, t, r, f));
 	KUNIT_EXPECT_EQ(test, damon_nr_regions(t), 1);
 
 	/* region started before the range */
 	r->ar.start = DAMON_MIN_REGION * 1;
 	r->ar.end = DAMON_MIN_REGION * 4;
-	KUNIT_EXPECT_FALSE(test, __damos_filter_out(NULL, t, r, f));
+	KUNIT_EXPECT_FALSE(test, damos_filter_match(NULL, t, r, f));
 	/* filter should have split the region */
 	KUNIT_EXPECT_EQ(test, r->ar.start, DAMON_MIN_REGION * 1);
 	KUNIT_EXPECT_EQ(test, r->ar.end, DAMON_MIN_REGION * 2);
@@ -465,7 +465,7 @@ static void damos_test_filter_out(struct kunit *test)
 	/* region started in the range */
 	r->ar.start = DAMON_MIN_REGION * 2;
 	r->ar.end = DAMON_MIN_REGION * 8;
-	KUNIT_EXPECT_TRUE(test, __damos_filter_out(NULL, t, r, f));
+	KUNIT_EXPECT_TRUE(test, damos_filter_match(NULL, t, r, f));
 	/* filter should have split the region */
 	KUNIT_EXPECT_EQ(test, r->ar.start, DAMON_MIN_REGION * 2);
 	KUNIT_EXPECT_EQ(test, r->ar.end, DAMON_MIN_REGION * 6);
-- 
2.39.5