Re: [Xen-devel] write_tsc in a PV domain?

[Jeremy Fitzhardinge <jeremy@xxxxxxxx>]

On 08/31/09 11:11, Dan Magenheimer wrote:
> I'm experimenting with clock_gettime(), gettimeofday(),
> and rdtsc with a 2.6.30 64-bit pvguest.  I have tried both
> with kernel.vsyscall64 equal to 0 and 1 (but haven't seen
> any significant difference between the two).  I have
> confirmed from sysfs that clocksource=xen
>   

Yeah, as I said, I wouldn't expect vsyscall to work under Xen at the
moment; the Xen clocksource will disable it.  Clocksources can implement
a "vread" method for use from a vsyscall, but from a quick look it
didn't appear we could use it as-is (because the pvclock info isn't
mapped into userspace, and the current vsyscall code assumes a single
set of parameters rather than percpu).

    J

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel