On 15.09.2011, at 23:36, Scott Wood wrote: > On 09/05/2011 05:30 PM, Alexander Graf wrote: >> >> On 27.08.2011, at 01:31, Scott Wood wrote: >> >>> +#ifdef CONFIG_E500 >>> + /* >>> + * Skip the overhead of HID0 accesses that KVM ignores -- >>> + * just write MSR[WE]. >>> + * >>> + * We don't need _TLF_NAPPING, because under KVM we know >>> + * it will take effect right away. >>> + */ >>> + if (ppc_md.power_save == e500_idle) >>> + ppc_md.power_save = kvm_msrwe_idle; >> >> Why the if() here? > > To avoid replacing some other power_save() implementation. > kvm_msrwe_idle() is a paravirt-optimized version of e500_idle(). > > However, now that e500_idle has an ifdef for e500mc, we'll need that > ifdef here as well. e500mc doesn't use MSR[WE] (and if it did, we > couldn't trap on it). For e500mc we'll want to make an hcall for idle > (ePAPR EV_IDLE).
Since we're PV'ing here either way, can't we simply define a generic power_save implementation that works across different CPU types? We could for example always use EV_IDLE. Alex -- To unsubscribe from this list: send the line "unsubscribe kvm-ppc" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
