[PATCH 2/5] drm/ttm: add busy and idle placement flags

[Christian König]

Am 31.08.21 um 15:18 schrieb Daniel Vetter:
> On Tue, Aug 31, 2021 at 01:21:07PM +0200, Christian König wrote:
>> More flexible than the busy placements.
>>
>> Signed-off-by: Christian König <christian.koenig at amd.com>
>> ---
>>   drivers/gpu/drm/ttm/ttm_bo.c    | 8 +++++++-
>>   include/drm/ttm/ttm_placement.h | 6 ++++++
>>   2 files changed, 13 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c
>> index 0a3127436f61..c7034040c67f 100644
>> --- a/drivers/gpu/drm/ttm/ttm_bo.c
>> +++ b/drivers/gpu/drm/ttm/ttm_bo.c
>> @@ -834,6 +834,9 @@ int ttm_bo_mem_space(struct ttm_buffer_object *bo,
>>   		const struct ttm_place *place = &placement->placement[i];
>>   		struct ttm_resource_manager *man;
>>   
>> +		if (place->flags & TTM_PL_FLAG_BUSY)
>> +			continue;
>> +
>>   		man = ttm_manager_type(bdev, place->mem_type);
>>   		if (!man || !ttm_resource_manager_used(man))
>>   			continue;
>> @@ -860,6 +863,9 @@ int ttm_bo_mem_space(struct ttm_buffer_object *bo,
>>   		const struct ttm_place *place = &placement->busy_placement[i];
>>   		struct ttm_resource_manager *man;
>>   
>> +		if (place->flags & TTM_PL_FLAG_IDLE)
>> +			continue;
>> +
>>   		man = ttm_manager_type(bdev, place->mem_type);
>>   		if (!man || !ttm_resource_manager_used(man))
>>   			continue;
>> @@ -869,7 +875,7 @@ int ttm_bo_mem_space(struct ttm_buffer_object *bo,
>>   		if (likely(!ret))
>>   			return 0;
>>   
>> -		if (ret && ret != -EBUSY)
>> +		if (ret != -EBUSY)
>>   			goto error;
>>   	}
>>   
>> diff --git a/include/drm/ttm/ttm_placement.h b/include/drm/ttm/ttm_placement.h
>> index 8995c9e4ec1b..63f7217354c0 100644
>> --- a/include/drm/ttm/ttm_placement.h
>> +++ b/include/drm/ttm/ttm_placement.h
>> @@ -53,6 +53,12 @@
>>   /* For multihop handling */
>>   #define TTM_PL_FLAG_TEMPORARY   (1 << 2)
>>   
>> +/* Placement is only used when we are evicting */
>> +#define TTM_PL_FLAG_BUSY	(1 << 3)
>> +
>> +/* Placement is only used when we are not evicting */
>> +#define TTM_PL_FLAG_IDLE	(1 << 4)
> Using an enum for this (with BIT() macro or so) and then slapping
> kerneldoc on top would be nice. That way you can also use the same enum in
> parameters and structures and it's all a bit easier to find and connect.

I don't really like to define flags as enums since they are not really 
an enumeration.

But some more kerneldoc sounds like a good idea to me.

> Otherwise I think this series makes sense, but probably better for nouveau
> folks to do review/testing.

Yeah, agree completely. I can do some smoke testing with nouveau, but 
that's about it.

Christian.

> -Daniel
>
>> +
>>   /**
>>    * struct ttm_place
>>    *
>> -- 
>> 2.25.1
>>