Re: [Mesa-dev] llvmpipe not supporting EGL_EXT_image_dma_buf_import ?
Yes, exactly - I would like to use the Docker container as a development/testing environment. Performance would not matter for that. Would be just good to be able to run the same code in Docker, which will later run on the real hardware. --Alex -Ursprüngliche Nachricht- Von: Christian König Gesendet: Freitag, 29. Oktober 2021 11:43 An: Michel Dänzer ; Irion, Alexander ; mesa-dev@lists.freedesktop.org Betreff: Re: [Mesa-dev] llvmpipe not supporting EGL_EXT_image_dma_buf_import ? Am 29.10.21 um 11:35 schrieb Michel Dänzer: > On 2021-10-28 14:02, Christian König wrote: >> Well I'm not an expert on llvmpipe, but as far as I know that's a general >> problem. >> >> DMA-buf is used by the Linux kernel drivers to pass hardware bufefrs between >> processes and drivers. >> >> Since llvmpipe as a software renderer it has no kernel driver, so there is >> no easy way to implement that. > Even if there was, CPU reads from dma-bufs imported from a HW driver > may be extremely slow, so they should be avoided other than for > specific setups where they're known to be guaranteed to perform > adequately. (This performance trap is why I think allowing mmap for > dma-buf fds was a mistake) Yeah, I'm not very keen of that either. But for testing I think it would still be nice to have the ability to share DMA-bufs with software rendereres even if it is horrible slow. Christian. - Siemens Electronic Design Automation GmbH; Anschrift: Arnulfstraße 201, 80634 München; Gesellschaft mit beschränkter Haftung; Geschäftsführer: Thomas Heurung, Frank Thürauf; Sitz der Gesellschaft: München; Registergericht München, HRB 106955
Re: [Mesa-dev] llvmpipe not supporting EGL_EXT_image_dma_buf_import ?
On 2021-10-28 14:02, Christian König wrote: > Well I'm not an expert on llvmpipe, but as far as I know that's a general > problem. > > DMA-buf is used by the Linux kernel drivers to pass hardware bufefrs between > processes and drivers. > > Since llvmpipe as a software renderer it has no kernel driver, so there is no > easy way to implement that. Even if there was, CPU reads from dma-bufs imported from a HW driver may be extremely slow, so they should be avoided other than for specific setups where they're known to be guaranteed to perform adequately. (This performance trap is why I think allowing mmap for dma-buf fds was a mistake) -- Earthling Michel Dänzer| https://redhat.com Libre software enthusiast | Mesa and Xwayland developer
Re: [Mesa-dev] llvmpipe not supporting EGL_EXT_image_dma_buf_import ?
Am 29.10.21 um 11:35 schrieb Michel Dänzer: On 2021-10-28 14:02, Christian König wrote: Well I'm not an expert on llvmpipe, but as far as I know that's a general problem. DMA-buf is used by the Linux kernel drivers to pass hardware bufefrs between processes and drivers. Since llvmpipe as a software renderer it has no kernel driver, so there is no easy way to implement that. Even if there was, CPU reads from dma-bufs imported from a HW driver may be extremely slow, so they should be avoided other than for specific setups where they're known to be guaranteed to perform adequately. (This performance trap is why I think allowing mmap for dma-buf fds was a mistake) Yeah, I'm not very keen of that either. But for testing I think it would still be nice to have the ability to share DMA-bufs with software rendereres even if it is horrible slow. Christian.
