Lucas Stach <l.stach@pengutronix.de> writes:

> Am Dienstag, den 05.06.2018, 12:03 -0700 schrieb Eric Anholt:
>> This isn't the first time I've had to argue to myself why the '++' was
>> safe.
>
> And now you need to do the same thing with me...
>
>> Signed-off-by: Eric Anholt <eric@anholt.net>
>> ---
>>  drivers/gpu/drm/v3d/v3d_fence.c | 3 +++
>>  1 file changed, 3 insertions(+)
>> 
>> diff --git a/drivers/gpu/drm/v3d/v3d_fence.c b/drivers/gpu/drm/v3d/v3d_fence.c
>> index bfe31a89668b..6265e9ab4a13 100644
>> --- a/drivers/gpu/drm/v3d/v3d_fence.c
>> +++ b/drivers/gpu/drm/v3d/v3d_fence.c
>> @@ -3,6 +3,9 @@
>>  
>>  #include "v3d_drv.h"
>>  
>> +/* Note that V3D fences are created during v3d_job_run(), so we're
>> + * already implictly locked.
>> + */
> I don't see where you would be locked in the job_run path. I think what
> you mean is that this path needs no locks, as it is driven by a single
> scheduler thread, right?

Yeah, it's only called from run_job, and run_job can't reenter.