Re: [PATCH -next v2] drm/amdgpu: return 'ret' in amdgpu_pmu_init

From: Julia Lawall
Date: Sat Jun 22 2019 - 09:06:20 EST




On Sat, 22 Jun 2019, Mao Wenan wrote:

> There is one warning:
> drivers/gpu/drm/amd/amdgpu/amdgpu_pmu.c: In function âamdgpu_pmu_initâ:
> drivers/gpu/drm/amd/amdgpu/amdgpu_pmu.c:249:6: warning: variable âretâ set but not used [-Wunused-but-set-variable]
> int ret = 0;
> ^
> amdgpu_pmu_init() is called by amdgpu_device_init() in drivers/gpu/drm/amd/amdgpu/amdgpu_device.c,
> which will use the return value. So it returns 'ret' for caller.
> amdgpu_device_init()
> r = amdgpu_pmu_init(adev);
>
> Fixes: 9c7c85f7ea1f ("drm/amdgpu: add pmu counters")
>
> Signed-off-by: Mao Wenan <maowenan@xxxxxxxxxx>
> ---
> v1->v2: change the subject for this patch; change the indenting when it calls init_pmu_by_type; use the value 'ret' in
> amdgpu_pmu_init().
> drivers/gpu/drm/amd/amdgpu/amdgpu_pmu.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_pmu.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_pmu.c
> index 0e6dba9..145e720 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_pmu.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_pmu.c
> @@ -252,8 +252,8 @@ int amdgpu_pmu_init(struct amdgpu_device *adev)
> case CHIP_VEGA20:
> /* init df */
> ret = init_pmu_by_type(adev, df_v3_6_attr_groups,
> - "DF", "amdgpu_df", PERF_TYPE_AMDGPU_DF,
> - DF_V3_6_MAX_COUNTERS);
> + "DF", "amdgpu_df", PERF_TYPE_AMDGPU_DF,
> + DF_V3_6_MAX_COUNTERS);
>
> /* other pmu types go here*/

I don't know what is the impact of the other pmu types that are planned
for the future. Perhaps it would be better to abort the function
immediately in the case of a failure.

julia

> break;
> @@ -261,7 +261,7 @@ int amdgpu_pmu_init(struct amdgpu_device *adev)
> return 0;
> }
>
> - return 0;
> + return ret;
> }
>
>
> --
> 2.7.4
>
>