Yiwei Zhang
7941d705c3
We observed that Venus on ANV on JSL platform has some cacheline flush issue. The overflush shows up as: 1. There're 2 threads venus bliting the feedback buffers suballocated from the same backing device memory, back to back. 2. On thread A, flushing the feedback buffer for cpu read is placed behind flushing a shader storage buffer for cpu read. 3. On thread B, flushing a different feedback buffer with the same backing device memory (different offset bound to) can kick the feedback buffer flush in (2) earlier than it should be flushed. 4. As a result, CPU polling thread for thread B results would see venus feedback buffer update earlier than shader storage buffer results being updated, breaking Venus sync primitives optimization. During investigation, a solid workaround for JSL platform is to force Venus to align up to 128 bytes for feedback buffer suballocation while the default is at 64 bytes. Cc: mesa-stable Signed-off-by: Yiwei Zhang <zzyiwei@chromium.org> Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/30879>
`Mesa <https://mesa3d.org>`_ - The 3D Graphics Library ====================================================== Source ------ This repository lives at https://gitlab.freedesktop.org/mesa/mesa. Other repositories are likely forks, and code found there is not supported. Build & install --------------- You can find more information in our documentation (`docs/install.rst <https://docs.mesa3d.org/install.html>`_), but the recommended way is to use Meson (`docs/meson.rst <https://docs.mesa3d.org/meson.html>`_): .. code-block:: sh $ meson setup build $ ninja -C build/ $ sudo ninja -C build/ install Support ------- Many Mesa devs hang on IRC; if you're not sure which channel is appropriate, you should ask your question on `OFTC's #dri-devel <irc://irc.oftc.net/dri-devel>`_, someone will redirect you if necessary. Remember that not everyone is in the same timezone as you, so it might take a while before someone qualified sees your question. To figure out who you're talking to, or which nick to ping for your question, check out `Who's Who on IRC <https://dri.freedesktop.org/wiki/WhosWho/>`_. The next best option is to ask your question in an email to the mailing lists: `mesa-dev\@lists.freedesktop.org <https://lists.freedesktop.org/mailman/listinfo/mesa-dev>`_ Bug reports ----------- If you think something isn't working properly, please file a bug report (`docs/bugs.rst <https://docs.mesa3d.org/bugs.html>`_). Contributing ------------ Contributions are welcome, and step-by-step instructions can be found in our documentation (`docs/submittingpatches.rst <https://docs.mesa3d.org/submittingpatches.html>`_). Note that Mesa uses gitlab for patches submission, review and discussions.