2021-05-31 01:57:23

by Bixuan Cui

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Subject: [PATCH -next] mm/mmap_lock: fix warning when CONFIG_TRACING is not defined

Fix the warning: [-Wunused-function]
mm/mmap_lock.c:157:20: warning: ‘get_mm_memcg_path’ defined but not used
static const char *get_mm_memcg_path(struct mm_struct *mm)
^~~~~~~~~~~~~~~~~

Signed-off-by: Bixuan Cui <[email protected]>
---
mm/mmap_lock.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/mmap_lock.c b/mm/mmap_lock.c
index 03ee85c696ef..ec7899b08690 100644
--- a/mm/mmap_lock.c
+++ b/mm/mmap_lock.c
@@ -154,7 +154,7 @@ static inline void put_memcg_path_buf(void)
* The caller must call put_memcg_path_buf() once the buffer is no longer
* needed. This must be done while preemption is still disabled.
*/
-static const char *get_mm_memcg_path(struct mm_struct *mm)
+static const char __maybe_unused *get_mm_memcg_path(struct mm_struct *mm)
{
char *buf = NULL;
struct mem_cgroup *memcg = get_mem_cgroup_from_mm(mm);
--
2.17.1


2021-05-31 02:03:41

by Matthew Wilcox

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Subject: Re: [PATCH -next] mm/mmap_lock: fix warning when CONFIG_TRACING is not defined

On Mon, May 31, 2021 at 09:55:27AM +0800, Bixuan Cui wrote:
> Fix the warning: [-Wunused-function]
> mm/mmap_lock.c:157:20: warning: ‘get_mm_memcg_path’ defined but not used
> static const char *get_mm_memcg_path(struct mm_struct *mm)
> ^~~~~~~~~~~~~~~~~

That seems like the wrong way to fix the warning. Why not put it
under an appropriate ifdef?

> Signed-off-by: Bixuan Cui <[email protected]>
> ---
> mm/mmap_lock.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/mm/mmap_lock.c b/mm/mmap_lock.c
> index 03ee85c696ef..ec7899b08690 100644
> --- a/mm/mmap_lock.c
> +++ b/mm/mmap_lock.c
> @@ -154,7 +154,7 @@ static inline void put_memcg_path_buf(void)
> * The caller must call put_memcg_path_buf() once the buffer is no longer
> * needed. This must be done while preemption is still disabled.
> */
> -static const char *get_mm_memcg_path(struct mm_struct *mm)
> +static const char __maybe_unused *get_mm_memcg_path(struct mm_struct *mm)
> {
> char *buf = NULL;
> struct mem_cgroup *memcg = get_mem_cgroup_from_mm(mm);
> --
> 2.17.1
>
>

2021-05-31 03:37:09

by Bixuan Cui

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Subject: Re: [PATCH -next] mm/mmap_lock: fix warning when CONFIG_TRACING is not defined



On 2021/5/31 10:02, Matthew Wilcox wrote:
>> Fix the warning: [-Wunused-function]
>> mm/mmap_lock.c:157:20: warning: ‘get_mm_memcg_path’ defined but not used
>> static const char *get_mm_memcg_path(struct mm_struct *mm)
>> ^~~~~~~~~~~~~~~~~
> That seems like the wrong way to fix the warning. Why not put it
> under an appropriate ifdef?
It's better than me, I will send a new patch.

Thanks
Bixuan Cui

>