Since May when Intel
first introduced their Graphics Execution Manager
after X.Org developers were enraged over Tungsten's TTM
memory manager and its development challenges, we've been talking about GEM several times since then.
Intel's Graphics Execution Manager is a kernel memory manager for graphics processors and has since overtaken TTM
in what will become the de facto standard for GPU memory management. A technical explanation of GEM can be found here
Intel has been working on merging GEM to master
since June and then in early August it was finally merged into xf86-video-intel
for the Intel driver's memory management needs. The GEM kernel component is still missing from the mainline Linux kernel. During XDS 2008
in September it was stated that GEM should be ready for the Linux 2.6.28 kernel
and that was confirmed again today as being ready for the next kernel release.
Due to the timing of GEM's introduction, DRI2 was dropped
from the X Server 1.5
/ X.Org 7.4
release due to its dependence on Tungsten's memory manager (though for X Server 1.6
it has been corrected
GEM had also caused the introduction of a new 2D acceleration architecture
for X that has been called UXA, or UMA Acceleration Architecture. Intel's Keith Packard though has clarified that UXA will eventually die off
with the GEM-related bits being moved back into the EXA architecture
Intel's Jesse Barnes has published a new blog post
talking about GEM for Linux 2.6.28 and other related topics. Jesse confirms that everything is still on track for being pushed into the Linux kernel once the 2.6.28 merge window is open. The kernel mode-setting
bits will be merged too. Additionally, Jesse stated the xf86-video-intel 2.5
release is still coming along and should be out soon. As a result of the Intel e1000e networking troubles
, he's also made a few PCI improvements that improve safety.