On Thu, Jun 02, 2022 at 08:47:56AM +0200, Daniel Vetter wrote: > > Two expand on this: > > - compositor opens the drm render /dev node > - compositor initializes the opengl or vulkan userspace driver on top of that > - compositor asks that userspace driver to allocate some buffer, which > can be pretty expensive > - compositor asks the userspace driver to export that buffer into a dma-buf > - compositor can finally do the test ioctl, realizes support isn't > there and tosses the entire thing > > read() on a sysfs file is so much more reasonable it's not even funny. >
What about dma-buf heaps? That should be a shorter route to getting a dma-buf fd if that's all that's needed. Cheers, -Brian
