AMDGPU Driver Looking To Re-Enable Performance-Boosting "Bulk Moves" Functionality
The LRU bulk moves patches were posted back in August of 2018 with the ability to help improve OpenCL and Vulkan performance for Radeon graphics. But prior to the release of the Linux 5.0 kernel that functionality was disabled for bugs.
Months have passed since then and apparently all of the bugs were ironed out in Linux 5.1. Linux 5.3 is being released this weekend followed by the Linux 5.4 cycle kicking off and now finally the AMD developers are talking of re-enabling this change to migrate PD/PT buffer objects onto the Least Recently Used (LRU) list in a single bulk operation.
Sent out today was the simple patch for reverting the previous disabling of LRU bulk moves.
It does turn out that it looks like the AMD Radeon Software for Linux packaged driver has been carrying this feature enabled as part of their packaged DKMS kernel driver. Given the timing of this patch though, while small, doesn't necessarily mean it will land for the upcoming Linux 5.4 cycle. Unless it's promoted as a "fix", the feature deadline for new DRM-Next features for Linux 5.4 passed a few weeks ago. We'll see how they play this out whether it will squeeze into Linux 5.4 as a fix or have to wait until Linux 5.5 in a few months.