Re: [PATCH 1/4] drm/virtio: pass gem reservation object to ttm init

From: Daniel Vetter
Date: Mon Jun 17 2019 - 10:16:48 EST


On Mon, Jun 17, 2019 at 04:08:25PM +0200, Daniel Vetter wrote:
> On Mon, Jun 17, 2019 at 01:14:03PM +0200, Gerd Hoffmann wrote:
> > With this gem and ttm will use the same reservation object,
> > so mixing and matching ttm / gem reservation helpers should
> > work fine.
> >
> > Signed-off-by: Gerd Hoffmann <kraxel@xxxxxxxxxx>
>
> While doing my prime doc+cleanup series I wondered whether we should do
> this for everyone, and perhaps even remove ttm_bo.ttm_resv. Only driver
> which doesn't yet have a gem_bo embedded in the same allocation is vmwgfx,
> and that would be easy to fix by adding a vmwgfx_resv somehwere.
>
> Anyway, looks like a solid start into the convergence story.
>
> Reviewed-by: Daniel Vetter <daniel.vetter@xxxxxxxx>

Aside: if virtio ever allows dma-buf sharing with something else (or
multiple virtio-gpu instances), then together with my patch series this
will fix dma-buf import. Atm virtio ignores the reservation object of the
imported dma-buf, which for foreing objects really isn't correct.
-Daniel

>
> > ---
> > drivers/gpu/drm/virtio/virtgpu_object.c | 3 ++-
> > 1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/virtio/virtgpu_object.c b/drivers/gpu/drm/virtio/virtgpu_object.c
> > index b2da31310d24..242766d644a7 100644
> > --- a/drivers/gpu/drm/virtio/virtgpu_object.c
> > +++ b/drivers/gpu/drm/virtio/virtgpu_object.c
> > @@ -132,7 +132,8 @@ int virtio_gpu_object_create(struct virtio_gpu_device *vgdev,
> > virtio_gpu_init_ttm_placement(bo);
> > ret = ttm_bo_init(&vgdev->mman.bdev, &bo->tbo, params->size,
> > ttm_bo_type_device, &bo->placement, 0,
> > - true, acc_size, NULL, NULL,
> > + true, acc_size, NULL,
> > + bo->gem_base.resv,
> > &virtio_gpu_ttm_bo_destroy);
> > /* ttm_bo_init failure will call the destroy */
> > if (ret != 0)
> > --
> > 2.18.1
> >
>
> --
> Daniel Vetter
> Software Engineer, Intel Corporation
> http://blog.ffwll.ch

--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch