2020-03-05 16:44:56

by Vincenzo Frascino

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

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 <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Vladimir Davydov <[email protected]>
Cc: Andrew Morton <[email protected]>
Signed-off-by: Vincenzo Frascino <[email protected]>
---
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

2020-03-05 17:23:33

by Johannes Weiner

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

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 <[email protected]>
> Cc: Michal Hocko <[email protected]>
> Cc: Vladimir Davydov <[email protected]>
> Cc: Andrew Morton <[email protected]>
> Signed-off-by: Vincenzo Frascino <[email protected]>

Acked-by: Johannes Weiner <[email protected]>

Thanks Vincenzo.

2020-03-05 18:37:05

by Chris Down

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

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 <[email protected]>
>Cc: Michal Hocko <[email protected]>
>Cc: Vladimir Davydov <[email protected]>
>Cc: Andrew Morton <[email protected]>
>Signed-off-by: Vincenzo Frascino <[email protected]>

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

Acked-by: Chris Down <[email protected]>

>---
> 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
>
>