mm/memcg: remove return value of mem_cgroup_scan_tasks()

No user checks the return value of mem_cgroup_scan_tasks(). Make the
return value void.

Link: https://lkml.kernel.org/r/20230616063030.977586-1-zhangpeng362@huawei.com
Signed-off-by: ZhangPeng <zhangpeng362@huawei.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Nanyong Sun <sunnanyong@huawei.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index c3d3a0c093156d6e1dc881c7d376f07a059a83b7..5818af8eca5a538dce3abbdef6464d5d5f3a1cb7 100644 (file)
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -820,8 +820,8 @@ struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *,
                                   struct mem_cgroup *,
                                   struct mem_cgroup_reclaim_cookie *);
 void mem_cgroup_iter_break(struct mem_cgroup *, struct mem_cgroup *);
-int mem_cgroup_scan_tasks(struct mem_cgroup *,
-                         int (*)(struct task_struct *, void *), void *);
+void mem_cgroup_scan_tasks(struct mem_cgroup *memcg,
+                          int (*)(struct task_struct *, void *), void *arg);
 
 static inline unsigned short mem_cgroup_id(struct mem_cgroup *memcg)
 {
@@ -1364,10 +1364,9 @@ static inline void mem_cgroup_iter_break(struct mem_cgroup *root,
 {
 }
 
-static inline int mem_cgroup_scan_tasks(struct mem_cgroup *memcg,
+static inline void mem_cgroup_scan_tasks(struct mem_cgroup *memcg,
                int (*fn)(struct task_struct *, void *), void *arg)
 {
-       return 0;
 }
 
 static inline unsigned short mem_cgroup_id(struct mem_cgroup *memcg)

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index cf06b1c9b3bb5b1b68255b607721b8492967c66e..a834b1edcde9e525231bcc36b3e705928d10ef04 100644 (file)
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1259,13 +1259,13 @@ static void invalidate_reclaim_iterators(struct mem_cgroup *dead_memcg)
  *
  * This function iterates over tasks attached to @memcg or to any of its
  * descendants and calls @fn for each task. If @fn returns a non-zero
- * value, the function breaks the iteration loop and returns the value.
- * Otherwise, it will iterate over all tasks and return 0.
+ * value, the function breaks the iteration loop. Otherwise, it will iterate
+ * over all tasks and return 0.
  *
  * This function must not be called for the root memory cgroup.
  */
-int mem_cgroup_scan_tasks(struct mem_cgroup *memcg,
-                         int (*fn)(struct task_struct *, void *), void *arg)
+void mem_cgroup_scan_tasks(struct mem_cgroup *memcg,
+                          int (*fn)(struct task_struct *, void *), void *arg)
 {
        struct mem_cgroup *iter;
        int ret = 0;
@@ -1285,7 +1285,6 @@ int mem_cgroup_scan_tasks(struct mem_cgroup *memcg,
                        break;
                }
        }
-       return ret;
 }
 
 #ifdef CONFIG_DEBUG_VM