[PATCH 2/2] drm/amdgpu: cleanup debugfs for amdgpu rings

[Das, Nirmoy]

On 9/5/2021 10:03 AM, Sharma, Shashank wrote:
>
>
> On 9/3/2021 9:44 PM, Das, Nirmoy wrote:
>> Hi Shashank,
>>
>> On 9/3/2021 5:51 PM, Das, Nirmoy wrote:
>>>
>>> On 9/3/2021 5:26 PM, Sharma, Shashank wrote:
>>>>
>>>>
>>>> On 9/3/2021 1:39 PM, Das, Nirmoy wrote:
>>>>>
>>>>> On 9/3/2021 8:36 AM, Sharma, Shashank wrote:
>>>>>>
>>>>>>
>>>>>> On 9/2/2021 5:14 PM, Nirmoy Das wrote:
>>>>>>> Use debugfs_create_file_size API for creating ring debugfs
>>>>>>> file, also cleanup surrounding code.
>>>>>>>
>>>>>>> Signed-off-by: Nirmoy Das <nirmoy.das at amd.com>
>>>>>>> ---
>>>>>>>   drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c |  4 +---
>>>>>>>   drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c    | 16 +++++-----------
>>>>>>>   drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h    |  8 +-------
>>>>>>>   3 files changed, 7 insertions(+), 21 deletions(-)
>>>>>>>
>>>>>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c 
>>>>>>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
>>>>>>> index 077f9baf74fe..dee56ab19a8f 100644
>>>>>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
>>>>>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
>>>>>>> @@ -1734,9 +1734,7 @@ int amdgpu_debugfs_init(struct 
>>>>>>> amdgpu_device *adev)
>>>>>>>           if (!ring)
>>>>>>>               continue;
>>>>>>>   -        if (amdgpu_debugfs_ring_init(adev, ring)) {
>>>>>>> -            DRM_ERROR("Failed to register debugfs file for 
>>>>>>> rings !\n");
>>>>>>> -        }
>>>>>>> +        amdgpu_debugfs_ring_init(adev, ring);
>>>>>>>       }
>>>>>>>         amdgpu_ras_debugfs_create_all(adev);
>>>>>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c 
>>>>>>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c
>>>>>>> index f40753e1a60d..968521d80514 100644
>>>>>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c
>>>>>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c
>>>>>>> @@ -415,26 +415,20 @@ static const struct file_operations 
>>>>>>> amdgpu_debugfs_ring_fops = {
>>>>>>>     #endif
>>>>>>>   -int amdgpu_debugfs_ring_init(struct amdgpu_device *adev,
>>>>>>> +void amdgpu_debugfs_ring_init(struct amdgpu_device *adev,
>>>>>>>                    struct amdgpu_ring *ring)
>>>>>>>   {
>>>>>>>   #if defined(CONFIG_DEBUG_FS)
>>>>>>>       struct drm_minor *minor = adev_to_drm(adev)->primary;
>>>>>>> -    struct dentry *ent, *root = minor->debugfs_root;
>>>>>>> +    struct dentry *root = minor->debugfs_root;
>>>>>>>       char name[32];
>>>>>>>         sprintf(name, "amdgpu_ring_%s", ring->name);
>>>>>>>   -    ent = debugfs_create_file(name,
>>>>>>> -                  S_IFREG | S_IRUGO, root,
>>>>>>> -                  ring, &amdgpu_debugfs_ring_fops);
>>>>>>> -    if (IS_ERR(ent))
>>>>>>> -        return -ENOMEM;
>>>>>>
>>>>>> Why are we doing this ? Why to make it void from int ?
>>>>>
>>>>>
>>>>> We tend to ignore debugfs return values as those are not serious 
>>>>> errors. This to sync with rest of our
>>>>>
>>>>> debugfs calls.
>>>>>
>>>>>
>>>>> Regards,
>>>>>
>>>>> Nirmoy
>>>>>
>>>>
>>>>
>>>> I am not suere if completely removing the provision of return value 
>>>> is a good way of doing it, we can always ignore it at the caller 
>>>> side, isn't it ?
>>
>>
>>
>> I just realized while making the change debugfs_create_file_size() is 
>> void return, so we don't have anything useful to return in 
>> amdgpu_debugfs_ring_init()
>>
>>
>
> Ah, it makes better sense now. Probably just a mention in the body of 
> the message that we are moving from debugfs_create_file() to 
> debugfs_create_file_size(), will make this change of return type more 
> logical.


Yes, I have that "Use debugfs_create_file_size API for creating ring 
debugfs file,..."


Nirmoy

>
> - Shashank
>
>> Regards,
>>
>> Nirmoy
>>
>>
>>>
>>>
>>> Yes, we are currently throwing an error msg and ignoring it. I don't 
>>> have a strong opinion regarding this, I will send a v2 restoring 
>>> previous behavior.
>>>
>>>
>>> Thanks,
>>>
>>> Nirmoy
>>>
>>>
>>>>
>>>> - Shashank
>>>>
>>>>>>
>>>>>> - Shashank
>>>>>>
>>>>>>
>>>>>>> -
>>>>>>> -    i_size_write(ent->d_inode, ring->ring_size + 12);
>>>>>>> -    ring->ent = ent;
>>>>>>> +    debugfs_create_file_size(name, S_IFREG | S_IRUGO, root, ring,
>>>>>>> +                 &amdgpu_debugfs_ring_fops,
>>>>>>> +                 ring->ring_size + 12);
>>>>>>>   #endif
>>>>>>> -    return 0;
>>>>>>>   }
>>>>>>>     /**
>>>>>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h 
>>>>>>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h
>>>>>>> index 88d80eb3fea1..c29fbce0a5b4 100644
>>>>>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h
>>>>>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h
>>>>>>> @@ -253,10 +253,6 @@ struct amdgpu_ring {
>>>>>>>       bool            has_compute_vm_bug;
>>>>>>>       bool            no_scheduler;
>>>>>>>       int            hw_prio;
>>>>>>> -
>>>>>>> -#if defined(CONFIG_DEBUG_FS)
>>>>>>> -    struct dentry *ent;
>>>>>>> -#endif
>>>>>>>   };
>>>>>>>     #define amdgpu_ring_parse_cs(r, p, ib) 
>>>>>>> ((r)->funcs->parse_cs((p), (ib)))
>>>>>>> @@ -356,8 +352,6 @@ static inline void 
>>>>>>> amdgpu_ring_write_multiple(struct amdgpu_ring *ring,
>>>>>>>     int amdgpu_ring_test_helper(struct amdgpu_ring *ring);
>>>>>>>   -int amdgpu_debugfs_ring_init(struct amdgpu_device *adev,
>>>>>>> +void amdgpu_debugfs_ring_init(struct amdgpu_device *adev,
>>>>>>>                    struct amdgpu_ring *ring);
>>>>>>> -void amdgpu_debugfs_ring_fini(struct amdgpu_ring *ring);
>>>>>>> -
>>>>>>>   #endif
>>>>>>>