On 18/02/15 13:11, Jan Beulich wrote: >>>> On 18.02.15 at 13:25, <andrew.coop...@citrix.com> wrote: >> The single use of the old rdtsc() in emulate_privileged_op() is altered to >> use >> the new rdtsc() and the rdmsr_writeback path to set eax/edx appropriately. > I'm not entirely sure about this one - the current code surely is slightly > faster than the replacement. Question is how much this matters. I'd > suggest to be on the safe side and simply open-code the asm() there.
It is a matter of a 4 instructions on a fault slowpath, which which only ever executed in the unlikely case that vtsc is enabled on a domain, or the kernel has set CR4.TSD. I would not loose sleep over the introduced inefficiently. ~Andrew _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
