Re: [PATCH 1/1] drm/amdgpu: init debugfs drm driver callback

["Das, Nirmoy" <nirmoy.das@amd.com>]

On 10/5/2021 2:41 PM, Christian König wrote:
>
>
> Am 05.10.21 um 14:20 schrieb Das, Nirmoy:
>> Hi Christian,
>>
>> On 10/5/2021 2:01 PM, Christian König wrote:
>>> Am 05.10.21 um 13:58 schrieb Nirmoy Das:
>>>> drm_dev_register() will try to init driver's debugfs using
>>>> drm_driver.debugfs_init call back function. Use that callback
>>>> also for amdgpu to intialize debugfs.
>>>
>>> Mhm, why is that useful? We rather wanted to get rid of all this DRM 
>>> midlayering.
>>
>>
>> Actually main issue I am trying to solve is:
>>
>> When user disables debugfs with CONFIG_DEBUG_FS_ALLOW_NONE, amdgpu 
>> gets EPERM and throws a DRM_ERROR even though it is not an error as 
>> this is user controllable.
>>
>> Shall I just make all debugfs error logs to DRM_WARN ?
>>
>> ref: 
>> https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgitlab.freedesktop.org%2Fdrm%2Famd%2F-%2Fissues%2F1686%23note_1052168&data=04%7C01%7Cnirmoy.das%40amd.com%7C63032bdca1394c92e88808d987fd867b%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637690345246933980%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=eXyj6wlxD0YGiNsjB4smmRAm2KKGRtq%2FWiDSMzEWTo8%3D&reserved=0
>
> Why not just add an "if (!root) return" at the beginning of 
> amdgpu_debugfs_init() ?


This is fine too, I will resend.


Nirmoy

>
> Regards,
> Christian.
>
>>
>> Regards,
>>
>> Nirmoy
>>
>>>
>>> Christian.
>>>
>>>>
>>>> Signed-off-by: Nirmoy Das <nirmoy.das@amd.com>
>>>> ---
>>>>   drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c | 10 +++++-----
>>>>   drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.h |  2 +-
>>>>   drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c     |  7 +++----
>>>>   3 files changed, 9 insertions(+), 10 deletions(-)
>>>>
>>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c 
>>>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
>>>> index 6611b3c7c149..3076742f8f85 100644
>>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
>>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
>>>> @@ -1611,8 +1611,9 @@ DEFINE_DEBUGFS_ATTRIBUTE(fops_ib_preempt, NULL,
>>>>   DEFINE_DEBUGFS_ATTRIBUTE(fops_sclk_set, NULL,
>>>>               amdgpu_debugfs_sclk_set, "%llu\n");
>>>>   -int amdgpu_debugfs_init(struct amdgpu_device *adev)
>>>> +void amdgpu_debugfs_init(struct drm_minor *minor)
>>>>   {
>>>> +    struct amdgpu_device *adev = drm_to_adev(minor->dev);
>>>>       struct dentry *root = adev_to_drm(adev)->primary->debugfs_root;
>>>>       struct dentry *ent;
>>>>       int r, i;
>>>> @@ -1621,14 +1622,14 @@ int amdgpu_debugfs_init(struct 
>>>> amdgpu_device *adev)
>>>>                     &fops_ib_preempt);
>>>>       if (IS_ERR(ent)) {
>>>>           DRM_ERROR("unable to create amdgpu_preempt_ib debugsfs 
>>>> file\n");
>>>> -        return PTR_ERR(ent);
>>>> +        return;
>>>>       }
>>>>         ent = debugfs_create_file("amdgpu_force_sclk", 0200, root, 
>>>> adev,
>>>>                     &fops_sclk_set);
>>>>       if (IS_ERR(ent)) {
>>>>           DRM_ERROR("unable to create amdgpu_set_sclk debugsfs 
>>>> file\n");
>>>> -        return PTR_ERR(ent);
>>>> +        return;
>>>>       }
>>>>         /* Register debugfs entries for amdgpu_ttm */
>>>> @@ -1682,11 +1683,10 @@ int amdgpu_debugfs_init(struct 
>>>> amdgpu_device *adev)
>>>>       debugfs_create_blob("amdgpu_discovery", 0444, root,
>>>>                   &adev->debugfs_discovery_blob);
>>>>   -    return 0;
>>>>   }
>>>>     #else
>>>> -int amdgpu_debugfs_init(struct amdgpu_device *adev)
>>>> +void amdgpu_debugfs_init(struct drm_minor *minor)
>>>>   {
>>>>       return 0;
>>>>   }
>>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.h 
>>>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.h
>>>> index 371a6f0deb29..06b68e16e35d 100644
>>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.h
>>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.h
>>>> @@ -27,7 +27,7 @@
>>>>    */
>>>>     int amdgpu_debugfs_regs_init(struct amdgpu_device *adev);
>>>> -int amdgpu_debugfs_init(struct amdgpu_device *adev);
>>>> +void amdgpu_debugfs_init(struct drm_minor *minor);
>>>>   void amdgpu_debugfs_fini(struct amdgpu_device *adev);
>>>>   void amdgpu_debugfs_fence_init(struct amdgpu_device *adev);
>>>>   void amdgpu_debugfs_firmware_init(struct amdgpu_device *adev);
>>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c 
>>>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
>>>> index df83b1f438b6..ceda650895db 100644
>>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
>>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
>>>> @@ -2012,10 +2012,6 @@ static int amdgpu_pci_probe(struct pci_dev 
>>>> *pdev,
>>>>               drm_fbdev_generic_setup(adev_to_drm(adev), 32);
>>>>       }
>>>>   -    ret = amdgpu_debugfs_init(adev);
>>>> -    if (ret)
>>>> -        DRM_ERROR("Creating debugfs files failed (%d).\n", ret);
>>>> -
>>>>       return 0;
>>>>     err_pci:
>>>> @@ -2479,6 +2475,9 @@ static const struct drm_driver 
>>>> amdgpu_kms_driver = {
>>>>       .dumb_map_offset = amdgpu_mode_dumb_mmap,
>>>>       .fops = &amdgpu_driver_kms_fops,
>>>>       .release = &amdgpu_driver_release_kms,
>>>> +#if defined(CONFIG_DEBUG_FS)
>>>> +    .debugfs_init = amdgpu_debugfs_init,
>>>> +#endif
>>>>         .prime_handle_to_fd = drm_gem_prime_handle_to_fd,
>>>>       .prime_fd_to_handle = drm_gem_prime_fd_to_handle,
>>>
>