On Thu, 2007-03-08 at 09:01 +0100, Ingo Molnar wrote: > * Jeremy Fitzhardinge <[EMAIL PROTECTED]> wrote: > > > > Your implementation is almost the perfect prototype, if you move the > > > 128 bit hackery into the hypervisor and hide it away from the kernel > > > :) > > > > The point is to use the tsc to avoid making any hypercalls, so dealing > > with the tsc->ns conversion has to happen on the guest side somehow. > > you are obsessed with avoiding a hypercall, but why? Granted it's slow > especially on things like SVN/VMX, but it's not fundamentally slow. We > definitely do not want to design our whole APIs and abstractions around > the temporary notion that 'hypercalls are slow'. I'd expect hypercalls > to be put into silicon just as much as SYSENTER was put into silicon.
Indeed, I expect them to fall somewhere between system calls and context switches. Perhaps not slow, but definitely worth minimising. > Anyway, in terms of guest time code, a /big/ amount of design junk can > be avoided by not trying to do sillynesses like 'virtual time'. The TSC > is awfully unreliable. You mean stolen time? I find this whole discussion really irritating, to be honest. I just want Thomas to implement the timer code for lguest, because that code scares me... I look forward to your patch 8) Rusty. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
