On Sun, Oct 8, 2017 at 6:03 AM, Theo de Raadt <dera...@openbsd.org> wrote:
> > Adam will correct me if I'm wrong, but his idea was to provide clock > > emulation to the operating system running in userland (solo5/unikernel). > > Perhaps vmd can make use of this interface too. > > But why does it matter if it knows the frequency? > Hi Mike, Theo yes, Mike you are correct. To provide more background, quoting the solo5 readme[https://github.com/ Solo5/solo5], "Solo5 is most useful as a "base layer" to run MirageOS unikernels, either on various existing hypervisors (KVM/QEMU, bhyve) or on a specialized "unikernel monitor" called ukvm." With the Help of Mike B and Mile L, i have been successfully running solo5 test kernels on ukvm (userland) and vmm (OpenBSD kernel) locally. ukvm needs to know the tsc frequency, so it can pass this information to a Solo5 unikernel which then uses rdtsc() to implement a clock. the following links to source code provide some more information solo5 unikernel clock implementation https://github.com/Solo5/solo5/blob/f8a277f83807333685742228ffef0d 87270207cf/kernel/ukvm/tscclock.c#L60-L106 solo5 unikernel clock initialisation https://github.com/Solo5/solo5/blob/9bad601c79ba7a549c87d22aaa970d 695e81e188/kernel/ukvm/time.c#L25 ukvm on OpenBSD setting up the tsc frequency https://github.com/adamsteen/solo5/blob/master/ukvm/ukvm_ hv_openbsd_x86_64.c#L137 and https://github.com/adamsteen/solo5/blob/200d7c4d4feb7aca62a3bae61f2ab1ec4bdd5bc9/ukvm/ukvm_hv_openbsd_x86_64.c#L52-L73 Cheers Adam
