[PATCH 7/7 v2] drm/radeon: Refuse to migrate a prime BO to VRAM. (v2)

[Alex Deucher]

On Mon, Apr 3, 2017 at 4:24 AM, Christian König <deathsimple at vodafone.de> wrote:
> Am 03.04.2017 um 05:35 schrieb raof at ubuntu.com:
>>
>> From: Christopher James Halse Rogers
>> <christopher.halse.rogers at canonical.com>
>>
>> BOs shared via dma-buf, either imported or exported, cannot sensibly be
>> migrated to VRAM
>> without breaking the dma-buf sharing. Refuse userspace requests to migrate
>> to VRAM,
>> ensure such BOs are not migrated during command submission, and refuse to
>> pin them
>> to VRAM.
>>
>> v2: Don't pin BOs in GTT. Instead, refuse to migrate BOs to VRAM.
>>
>> Signed-off-by: Christopher James Halse Rogers
>> <christopher.halse.rogers at canonical.com>
>
>
> Patches #4, #6 and this one (#7) are Reviewed-by: Christian König
> <christian.koenig at amd.com>.

Will this cause any issues with self sharing?  E.g., the standard use
case with a single GPU and DRI3?

Alex

>
>
>> ---
>>   drivers/gpu/drm/radeon/radeon_cs.c     | 10 ++++++++++
>>   drivers/gpu/drm/radeon/radeon_gem.c    |  4 ++++
>>   drivers/gpu/drm/radeon/radeon_object.c |  5 +++++
>>   3 files changed, 19 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/radeon/radeon_cs.c
>> b/drivers/gpu/drm/radeon/radeon_cs.c
>> index a8442f7196d6..df6b58c08544 100644
>> --- a/drivers/gpu/drm/radeon/radeon_cs.c
>> +++ b/drivers/gpu/drm/radeon/radeon_cs.c
>> @@ -164,6 +164,16 @@ static int radeon_cs_parser_relocs(struct
>> radeon_cs_parser *p)
>>                         p->relocs[i].allowed_domains = domain;
>>                 }
>>   +             /* Objects shared as dma-bufs cannot be moved to VRAM */
>> +               if (p->relocs[i].robj->prime_shared_count) {
>> +                       p->relocs[i].allowed_domains &=
>> ~RADEON_GEM_DOMAIN_VRAM;
>> +                       if (!p->relocs[i].allowed_domains) {
>> +                               DRM_ERROR("BO associated with dma-buf
>> cannot "
>> +                                         "be moved to VRAM\n");
>> +                               return -EINVAL;
>> +                       }
>> +               }
>> +
>>                 p->relocs[i].tv.bo = &p->relocs[i].robj->tbo;
>>                 p->relocs[i].tv.shared = !r->write_domain;
>>   diff --git a/drivers/gpu/drm/radeon/radeon_gem.c
>> b/drivers/gpu/drm/radeon/radeon_gem.c
>> index 96683f5b2b1b..067ea7d7658a 100644
>> --- a/drivers/gpu/drm/radeon/radeon_gem.c
>> +++ b/drivers/gpu/drm/radeon/radeon_gem.c
>> @@ -120,6 +120,10 @@ static int radeon_gem_set_domain(struct
>> drm_gem_object *gobj,
>>                         return r;
>>                 }
>>         }
>> +       if (domain == RADEON_GEM_DOMAIN_VRAM && robj->prime_shared_count)
>> {
>> +               /* A BO that is associated with a dma-buf cannot be
>> sensibly migrated to VRAM */
>> +               return -EINVAL;
>> +       }
>>         return 0;
>>   }
>>   diff --git a/drivers/gpu/drm/radeon/radeon_object.c
>> b/drivers/gpu/drm/radeon/radeon_object.c
>> index 74b276060c20..bec2ec056de4 100644
>> --- a/drivers/gpu/drm/radeon/radeon_object.c
>> +++ b/drivers/gpu/drm/radeon/radeon_object.c
>> @@ -352,6 +352,11 @@ int radeon_bo_pin_restricted(struct radeon_bo *bo,
>> u32 domain, u64 max_offset,
>>                 return 0;
>>         }
>> +       if (bo->prime_shared_count && domain == RADEON_GEM_DOMAIN_VRAM) {
>> +               /* A BO shared as a dma-buf cannot be sensibly migrated to
>> VRAM */
>> +               return -EINVAL;
>> +       }
>> +
>>         radeon_ttm_placement_from_domain(bo, domain);
>>         for (i = 0; i < bo->placement.num_placement; i++) {
>>                 /* force to pin into visible video ram */
>
>
>
> _______________________________________________
> amd-gfx mailing list
> amd-gfx at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/amd-gfx