Re: [Patch v1 1/4] drm/amdgpu/userq: no need to use local variable ret

["Christian König" <christian.koenig@amd.com>]

On 3/26/26 13:26, Khatri, Sunil wrote:
> 
> On 26-03-2026 05:38 pm, Christian König wrote:
>> On 3/26/26 09:55, Sunil Khatri wrote:
>>> In function amdgpu_userq_evict use the function return
>>> value in the if condition instead.
>>>
>>> Signed-off-by: Sunil Khatri <sunil.khatri@amd.com>
>>> ---
>>>  drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c | 8 ++------
>>>  1 file changed, 2 insertions(+), 6 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c
>>> index aa0e6eea9436..2a1832fce6d2 100644
>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c
>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c
>>> @@ -1308,17 +1308,13 @@ void
>>>  amdgpu_userq_evict(struct amdgpu_userq_mgr *uq_mgr)
>>>  {
>>>  	struct amdgpu_device *adev = uq_mgr->adev;
>>> -	int ret;
>>>  
>>>  	/* Wait for any pending userqueue fence work to finish */
>>> -	ret = amdgpu_userq_wait_for_signal(uq_mgr);
>>> -	if (ret)
>>> +	if (amdgpu_userq_wait_for_signal(uq_mgr))
>>>  		dev_err(adev->dev, "Not evicting userqueue, timeout waiting for work\n");
>> That actually looks like a pretty bad idea. Instead we should start printing the error code.
> Sure could add an error code in the logging.
>> But before we do that I would rather like to know why amdgpu_userq_wait_for_signal() can fail?
> dma_fence_wait_timeout is what could fail and we are returning -ETIMEDOUT. We could totally avoid checking for the error here completely as we are already printing the error in
> the called function below.
> ret=dma_fence_wait_timeout(f, true, msecs_to_jiffies(100));

*sigh* I explicitly NAKed that timeout before. Please change that to the maximum.

Additional to that please drop the extra call to dma_fence_is_signaled() before the wait, such stuff is completely superfluous.

Then the second parameter to dma_fence_wait_timeout should be false, this way we can't be interrupted any more and don't need to check the return value for errors.

Thanks for take a look at that,
Christian.

>                 if(ret<=0) {
>                         drm_file_err(uq_mgr->file, "Timed out waiting for fence=%llu:%llu\n",
>                                      f->context, f->seqno);
>         return-ETIMEDOUT;
>                 }
>> That should never happen in the first place.
>>
>> Regards,
>> Christian.
>>
>>>  
>>> -	ret = amdgpu_userq_evict_all(uq_mgr);
>>> -	if (ret)
>>> +	if (amdgpu_userq_evict_all(uq_mgr))
>>>  		dev_err(adev->dev, "Failed to evict userqueue\n");
> Here also the below function returns error and printing error too. We could avoid the return value here too as we are already printing the error.
> amdgpu_userq_preempt_helper(queue);
>                 if(r)
>                         ret=r;
> 
> 
> Regards
> Sunil Khatri
> 
>>> -
>>>  }
>>>  
>>>  int amdgpu_userq_mgr_init(struct amdgpu_userq_mgr *userq_mgr, struct drm_file *file_priv,