[PATCH v2] drm/amdgpu: lock the eviction fence for wq signals it

[Yadav, Arvind]

Reviewed-by: Arvind Yadav <Arvind.Yadav at amd.com>

On 5/14/2025 9:02 PM, Alex Deucher wrote:
> On Sun, May 11, 2025 at 10:21 PM Prike Liang <Prike.Liang at amd.com> wrote:
>> Lock and refer to the eviction fence before the eviction fence
>> schedules work queue tries to signal it.
>>
>> Suggested-by: Christian König <christian.koenig at amd.com>
>> Signed-off-by: Prike Liang <Prike.Liang at amd.com>
> Acked-by: Alex Deucher <alexander.deucher at amd.com>
>
>> ---
>>   drivers/gpu/drm/amd/amdgpu/amdgpu_eviction_fence.c | 8 +++++++-
>>   1 file changed, 7 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_eviction_fence.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_eviction_fence.c
>> index 1a7469543db5..d5f176fef357 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_eviction_fence.c
>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_eviction_fence.c
>> @@ -108,12 +108,18 @@ amdgpu_eviction_fence_suspend_worker(struct work_struct *work)
>>          struct amdgpu_eviction_fence *ev_fence;
>>
>>          mutex_lock(&uq_mgr->userq_mutex);
>> +       spin_lock(&evf_mgr->ev_fence_lock);
>>          ev_fence = evf_mgr->ev_fence;
>> -       if (!ev_fence)
>> +       spin_unlock(&evf_mgr->ev_fence_lock);
>> +
>> +       if (ev_fence)
>> +               dma_fence_get(&ev_fence->base);
>> +       else
>>                  goto unlock;
>>
>>          amdgpu_userq_evict(uq_mgr, ev_fence);
>>
>> +       dma_fence_put(&ev_fence->base);
>>   unlock:
>>          mutex_unlock(&uq_mgr->userq_mutex);
>>   }
>> --
>> 2.34.1
>>