[RFC PATCH v2.2 06/17] mm/damon/core: commit preps

SJ Park <[email protected]> Mon, 27 Jul 2026 21:12:27 -0700
Newsgroups dev.linux.lists.damon,org.kernel.vger.linux-kernel,org.kvack.linux-mm
Message-ID <[email protected]>
damon_commit_probes() is ignoring damon_prep.  Commit the prep actions,
too.

Signed-off-by: SJ Park <[email protected]>
---
 mm/damon/core.c | 59 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 59 insertions(+)

diff --git a/mm/damon/core.c b/mm/damon/core.c
index e8b5e6e43f9d4..01715648f6e0c 100644
--- a/mm/damon/core.c
+++ b/mm/damon/core.c
@@ -128,11 +128,34 @@ void damon_add_prep(struct damon_probe *p, struct damon_prep *prep)
 	list_add_tail(&prep->list, &p->preps);
 }
 
+static void damon_del_prep(struct damon_prep *p)
+{
+	list_del(&p->list);
+}
+
 static void damon_free_prep(struct damon_prep *p)
 {
 	kfree(p);
 }
 
+static void damon_destroy_prep(struct damon_prep *p)
+{
+	damon_del_prep(p);
+	damon_free_prep(p);
+}
+
+static struct damon_prep *damon_nth_prep(int n, struct damon_probe *p)
+{
+	struct damon_prep *prep;
+	int i = 0;
+
+	damon_for_each_prep(prep, p) {
+		if (i++ == n)
+			return prep;
+	}
+	return NULL;
+}
+
 struct damon_filter *damon_new_filter(enum damon_filter_type type,
 		bool matching, bool allow)
 {
@@ -1687,6 +1710,36 @@ static int damon_commit_targets(
 	return err;
 }
 
+static void damon_commit_prep(struct damon_prep *dst, struct damon_prep *src)
+{
+	dst->action = src->action;
+}
+
+static int damon_commit_preps(struct damon_probe *dst, struct damon_probe *src)
+{
+	struct damon_prep *dst_prep, *next, *src_prep, *new_prep;
+	int i = 0, j = 0;
+
+	damon_for_each_prep_safe(dst_prep, next, dst) {
+		src_prep = damon_nth_prep(i++, src);
+		if (src_prep)
+			damon_commit_prep(dst_prep, src_prep);
+		else
+			damon_destroy_prep(dst_prep);
+	}
+
+	damon_for_each_prep_safe(src_prep, next, src) {
+		if (j++ < i)
+			continue;
+
+		new_prep = damon_new_prep(src_prep->action);
+		if (!new_prep)
+			return -ENOMEM;
+		damon_add_prep(dst, new_prep);
+	}
+	return 0;
+}
+
 static void damon_commit_filter(struct damon_filter *dst,
 		struct damon_filter *src)
 {
@@ -1745,6 +1798,9 @@ static int damon_commit_probes(struct damon_ctx *dst, struct damon_ctx *src)
 		src_probe = damon_nth_probe(i++, src);
 		if (src_probe) {
 			dst_probe->weight = src_probe->weight;
+			err = damon_commit_preps(dst_probe, src_probe);
+			if (err)
+				return err;
 			err = damon_commit_filters(dst_probe, src_probe);
 			if (err)
 				return err;
@@ -1762,6 +1818,9 @@ static int damon_commit_probes(struct damon_ctx *dst, struct damon_ctx *src)
 			return -ENOMEM;
 		damon_add_probe(dst, new_probe);
 		new_probe->weight = src_probe->weight;
+		err = damon_commit_preps(new_probe, src_probe);
+		if (err)
+			return err;
 		err = damon_commit_filters(new_probe, src_probe);
 		if (err)
 			return err;
-- 
2.47.3