Re: [PATCH v3 4/5] drm/sched: Use drm sched lockdep map for submit_wq

["Ghimiray, Himal Prasad" <himal.prasad.ghimiray@intel.com>]

On 14-08-2024 00:46, Matthew Brost wrote:
> On Mon, Aug 12, 2024 at 11:05:31AM +0530, Ghimiray, Himal Prasad wrote:
>>
>>
>> On 10-08-2024 03:58, Matthew Brost wrote:
>>> Avoid leaking a lockdep map on each drm sched creation and destruction
>>> by using a single lockdep map for all drm sched allocated submit_wq.
>>>
>>> v2:
>>>    - Use alloc_ordered_workqueue_lockdep_map (Tejun)
>>>
>>> Cc: Luben Tuikov <ltuikov89@gmail.com>
>>> Cc: Christian König <christian.koenig@amd.com>
>>> Signed-off-by: Matthew Brost <matthew.brost@intel.com>
>>> ---
>>>    drivers/gpu/drm/scheduler/sched_main.c | 11 +++++++++++
>>>    1 file changed, 11 insertions(+)
>>>
>>> diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
>>> index ab53ab486fe6..cf79d348cb32 100644
>>> --- a/drivers/gpu/drm/scheduler/sched_main.c
>>> +++ b/drivers/gpu/drm/scheduler/sched_main.c
>>> @@ -87,6 +87,12 @@
>>>    #define CREATE_TRACE_POINTS
>>>    #include "gpu_scheduler_trace.h"
>>> +#ifdef CONFIG_LOCKDEP
>>> +static struct lockdep_map drm_sched_lockdep_map = {
>>> +	.name = "drm_sched_lockdep_map"
>>> +};
>>
>>
>> will it be better to use STATIC_LOCKDEP_MAP_INIT ? Initializing key here
>> instead of while registering the class ?
>>
> 
> Most existing design patterns in the kernel define static lockdep class
> this way so I think this is fine. But honestly don't really have an
> opinion here.
> 
> Matt

In that case, I have no concerns with the current initialization.


> 
>>
>>> +#endif
>>> +
>>>    #define to_drm_sched_job(sched_job)		\
>>>    		container_of((sched_job), struct drm_sched_job, queue_node)
>>> @@ -1272,7 +1278,12 @@ int drm_sched_init(struct drm_gpu_scheduler *sched,
>>>    		sched->submit_wq = submit_wq;
>>>    		sched->own_submit_wq = false;
>>>    	} else {
>>> +#ifdef CONFIG_LOCKDEP
>>> +		sched->submit_wq = alloc_ordered_workqueue_lockdep_map(name, 0,
>>> +								       &drm_sched_lockdep_map);
>>> +#else
>>>    		sched->submit_wq = alloc_ordered_workqueue(name, 0);
>>> +#endif
>>>    		if (!sched->submit_wq)
>>>    			return -ENOMEM;