On Tue, Feb 14, 2017 at 13:37:56 -0500, James J. Nutaro wrote: > This patch adds an interface for pacing the execution of QEMU to match an > external > simulation clock. Its aim is to permit QEMU to be used as a module within a > larger simulation system. (snip) > +++ b/docs/simulation-sync.txt > @@ -0,0 +1,59 @@ > += Synchronizing the virtual clock with an external source = > + > +QEMU has a protocol for synchronizing its virtual clock > +with the clock of a simulator in which QEMU is embedded > +as a component. This options is enabled with the -qqq > +argument, and it should generally be accompanied by the > +following additional command line arguments: > + > +-icount 1,sleep=off -rtc clock=vm > + or > +-enable-kvm -rtc clock=vm
Isn't this a KVM-only feature though? I don't see calls to qqq_sync() anywhere but from kvm-all.c, but maybe I'm missing something. Also, a few more comments: - Why "qqq" as the name for this feature? I fail to see any connection between the name and the feature. - If Windows users ever wanted this feature, would we have to change the user-facing API (i.e. the -qqq parameter)? - As is, isn't the code Unix-only rather than Linux-only? Thanks, Emilio