On 16/03/15 13:16, Peter Zijlstra wrote: > Hi Waiman, > > As promised; here is the paravirt stuff I did during the trip to BOS last week. > > All the !paravirt patches are more or less the same as before (the only real > change is the copyright lines in the first patch). > > The paravirt stuff is 'simple' and KVM only -- the Xen code was a little more > convoluted and I've no real way to test that but it should be stright fwd to > make work. > > I ran this using the virtme tool (thanks Andy) on my laptop with a 4x > overcommit on vcpus (16 vcpus as compared to the 4 my laptop actually has) and > it both booted and survived a hackbench run (perf bench sched messaging -g 20 > -l 5000). > > So while the paravirt code isn't the most optimal code ever conceived it does work. > > Also, the paravirt patching includes replacing the call with "movb $0, %arg1" > for the native case, which should greatly reduce the cost of having > CONFIG_PARAVIRT_SPINLOCKS enabled on actual hardware. > > I feel that if someone were to do a Xen patch we can go ahead and merge this > stuff (finally!). I can look at this. It looks pretty straight-forward. > These patches do not implement the paravirt spinlock debug stats currently > implemented (separately) by KVM and Xen, but that should not be too hard to do > on top and in the 'generic' code -- no reason to duplicate all that. I think this is fine. David -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
