[PATCH v2] mm: Make mem_cgroup_id_get_many() __maybe_unused

[PATCH v2] mm: Make mem_cgroup_id_get_many() __maybe_unused

[Vincenzo Frascino]

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@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
---
 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

Re: [PATCH v2] mm: Make mem_cgroup_id_get_many() __maybe_unused

[Johannes Weiner]

On Thu, Mar 05, 2020 at 04:43:54PM +0000, Vincenzo Frascino wrote:
> 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@cmpxchg.org>
> Cc: Michal Hocko <mhocko@kernel.org>
> Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>

Acked-by: Johannes Weiner <hannes@cmpxchg.org>

Thanks Vincenzo.

Re: [PATCH v2] mm: Make mem_cgroup_id_get_many() __maybe_unused

[Chris Down]

Vincenzo Frascino writes:
>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@cmpxchg.org>
>Cc: Michal Hocko <mhocko@kernel.org>
>Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
>Cc: Andrew Morton <akpm@linux-foundation.org>
>Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>

Thanks, I didn't notice you've already posted it before replying on v1 :-)

Acked-by: Chris Down <chris@chrisdown.name>

>---
> 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
>
>