arm: kvm-selftest

Hi Christoffer,

I'm just confirming that I found the right repo/branch for the most recent kvmarm unit tests. I'm looking at

github.com/virtualopensystems/linux-kvm-arm kvm-selftest

with last commit

commit b5aec35ee58c6b2d726a3e2fb56ec0e6e89976e0

Author: Christoffer Dall <[email protected]>
Date:   Fri Feb 15 18:37:24 2013 -0500

WIP: These settings are useful for some more profiling

This really needs to be cleaned up and stuff, but the whole testing here has bit-rotted and should be picked up by someone.

I know....

If this is the most recent branch, then I guess I'll volunteer myself to be the someone to pick it up and see about integrating it into kvm-unit-tests.

thanks,
drew

Hi Drew,

Yes, this is the right repo and the latest commit. You may in fact benefit from looking at a slightly earlier state of the repo which may be a bit more clean. There may also be some newer commits in some *-selftest*-named branches in https://github.com/columbia/linux-kvm-arm.
At least, at some point I added a test that measures IPI cost similarly to what was done on x86.

Note that the simple VMEXIT count probably doesn't work out-of-the-box, because reading the cycle counter on ARM requires access to the PMU registers, which are current trapped and RAZ. I haven't looked closely at the provisions in the ARM ARM and the TRMs to see if there's some way we can allow the guest access to these. Otherwise a PV interface may be necessary. Will Deacon can probably help us answer these questions.

-Christoffer