From 8c02207a064ddf66ae1d4ba1fbb9a50d1a127bd7 Mon Sep 17 00:00:00 2001
From: SJ Park <sj@kernel.org>
Date: Tue, 30 Jun 2026 07:17:23 -0700
Subject: [PATCH] mm/damon/sysfs: split probe setup function out

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.

Link: https://lore.kernel.org/20260630141726.92246-10-sj@kernel.org
Signed-off-by: SJ Park <sj@kernel.org>
Cc: Brendan Higgins <brendan.higgins@linux.dev>
Cc: David Hildenbrand <david@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.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 e3526a263e20..02afd37b04df 100644
--- a/mm/damon/sysfs.c
+++ b/mm/damon/sysfs.c
@@ -1909,47 +1909,59 @@ 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)
+{
+	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];
+		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;
+			}
+		}
+		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;
+	int i, err;
 
 	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;
+		struct damon_sysfs_probe *sys_probe;
+		struct damon_probe *p;
 
-		if (!sys_filters)
-			continue;
-		c = damon_new_probe();
-		if (!c)
+		p = damon_new_probe();
+		if (!p)
 			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;
-				}
-			}
-			damon_add_filter(c, filter);
-		}
+		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;
 }