From: SeongJae Park <sj@kernel.org>
Date: Mon, 18 May 2026 23:41:14 +0000 (-0700)
Subject: mm/damon/sysfs: setup damon_filter->memcg_id from path
X-Git-Url: http://git.ipfire.org/gitweb/?a=commitdiff_plain;h=543ab01db7ace5bb28972ac70f321d55cc4f0214;p=thirdparty%2Flinux.git

mm/damon/sysfs: setup damon_filter->memcg_id from path

Find and set the memcg_id for damon_filter from the user-passed memory
cgroup path when updating the DAMON input parameters.

Link: https://lore.kernel.org/20260518234119.97569-27-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
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: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

diff --git a/include/linux/damon.h b/include/linux/damon.h
index 6a54c601889b..4014fd0d463c 100644
--- a/include/linux/damon.h
+++ b/include/linux/damon.h
@@ -1006,6 +1006,7 @@ static inline unsigned long damon_sz_region(struct damon_region *r)
 struct damon_filter *damon_new_filter(enum damon_filter_type type,
 		bool matching, bool allow);
 void damon_add_filter(struct damon_probe *probe, struct damon_filter *f);
+void damon_destroy_filter(struct damon_filter *f);
 
 struct damon_probe *damon_new_probe(void);
 void damon_add_probe(struct damon_ctx *ctx, struct damon_probe *probe);
diff --git a/mm/damon/core.c b/mm/damon/core.c
index 9a5a835a4d3f..4e223857a0f9 100644
--- a/mm/damon/core.c
+++ b/mm/damon/core.c
@@ -143,7 +143,7 @@ static void damon_free_filter(struct damon_filter *f)
 	kfree(f);
 }
 
-static void damon_destroy_filter(struct damon_filter *f)
+void damon_destroy_filter(struct damon_filter *f)
 {
 	damon_del_filter(f);
 	damon_free_filter(f);
diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c
index 0f6379caf481..2e95e3bac774 100644
--- a/mm/damon/sysfs.c
+++ b/mm/damon/sysfs.c
@@ -1927,6 +1927,17 @@ static int damon_sysfs_set_probes(struct damon_ctx *ctx,
 					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);
 		}
 	}