Hey there,
I was asked today in the board meeting about the use of NEON routines in the kernel; I said we had looked into this but hadn't done it because a) it wasn't conclusively better and b) if better, it would need to be done conditionally per-platform. But I wanted to double-check that's actually true (and I'm copying Vijay to keep me honest). I have some references:
http://lists.linaro.org/pipermail/linaro-toolchain/2011-January/000722.html
http://groups.google.com/group/beagleboard/browse_thread/thread/12c7bd415fbc...
http://www.spinics.net/lists/arm-kernel/msg106503.html
http://dev.gentoo.org/~armin76/arm/memcpy-neon_result.txt
https://wiki.linaro.org/WorkingGroups/ToolChain/Benchmarks/InitialMemcpy?hig... https://wiki.linaro.org/WorkingGroups/ToolChain/StringRoutines?highlight=%28...
Incidentally, this ties into the question sent earlier this week which had to do with Nico's work item in:
https://blueprints.launchpad.net/linux-linaro/+spec/other-kernel-thumb2
Which IIRC Nico says probably isn't worth it, right?