External clients which import our bo's wait only for exclusive dmabuf-fences, not on shared ones, so attach fences on such exported buffers as exclusive ones.
See discussion in thread: https://lists.freedesktop.org/archives/dri-devel/2016-October/122370.html Tested on Intel iGPU + AMD Tonga dGPU as DRI3/Present Prime render offload, and with the Tonga standalone as primary gpu. v2: Add a wait for all shared fences before prime export, as suggested by Christian Koenig. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=95472 (v1) Tested-by: Mike Lothian <mike at fireburn.co.uk> Signed-off-by: Mario Kleiner <mario.kleiner.de at gmail.com> Cc: Christian König <christian.koenig at amd.com> Cc: Michel Dänzer <michel.daenzer at amd.com> --- drivers/gpu/drm/amd/amdgpu/amdgpu.h | 1 + drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c | 2 +- drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c | 11 +++++++++++ 3 files changed, 13 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h index 039b57e..a337d56 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h @@ -459,6 +459,7 @@ struct amdgpu_bo { u64 metadata_flags; void *metadata; u32 metadata_size; + bool prime_exported; /* list of all virtual address to which this bo * is associated to */ diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c index 651115d..51c6f60 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c @@ -132,7 +132,7 @@ static int amdgpu_bo_list_set(struct amdgpu_device *adev, entry->priority = min(info[i].bo_priority, AMDGPU_BO_LIST_MAX_PRIORITY); entry->tv.bo = &entry->robj->tbo; - entry->tv.shared = true; + entry->tv.shared = !entry->robj->prime_exported; if (entry->robj->prefered_domains == AMDGPU_GEM_DOMAIN_GDS) gds_obj = entry->robj; diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c index 7700dc2..0ed92a1 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c @@ -117,9 +117,20 @@ struct dma_buf *amdgpu_gem_prime_export(struct drm_device *dev, int flags) { struct amdgpu_bo *bo = gem_to_amdgpu_bo(gobj); + long ret; if (amdgpu_ttm_tt_get_usermm(bo->tbo.ttm)) return ERR_PTR(-EPERM); + /* + * Wait for all shared fences to complete before we switch to future + * use of exclusive fence on this prime_exported bo. + */ + ret = reservation_object_wait_timeout_rcu(bo->tbo.resv, true, false, + MAX_SCHEDULE_TIMEOUT); + WARN(ret <= 0, "Fence wait returns %li\n", ret); + + bo->prime_exported = true; + return drm_gem_prime_export(dev, gobj, flags); } -- 2.7.4
