mem_cgroup_id_get_many() is currently used only when MMU or MEMCG_SWAP configuration options are enabled. Having them disabled triggers the following warning at compile time: linux/mm/memcontrol.c:4797:13: warning: ‘mem_cgroup_id_get_many’ defined but not used [-Wunused-function] static void mem_cgroup_id_get_many(struct mem_cgroup *memcg, unsigned int n) Make mem_cgroup_id_get_many() __maybe_unused to address the issue. Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxxxx> Cc: Vladimir Davydov <vdavydov.dev@xxxxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@xxxxxxx> --- mm/memcontrol.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index d09776cd6e10..2b9533ed52f5 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -4794,7 +4794,8 @@ static void mem_cgroup_id_remove(struct mem_cgroup *memcg) } } -static void mem_cgroup_id_get_many(struct mem_cgroup *memcg, unsigned int n) +static void __maybe_unused mem_cgroup_id_get_many(struct mem_cgroup *memcg, + unsigned int n) { refcount_add(n, &memcg->id.ref); } -- 2.25.1