On Tue, 2012-07-10 at 19:47 -0500, Scott Wood wrote: > On 07/10/2012 07:44 PM, Alexander Graf wrote: > > > > On 11.07.2012, at 02:34, Scott Wood wrote: > >> +#ifdef CONFIG_BOOKE > >> + /* > >> + * We're not changing address space on Book E, and the extra rfi > >> + * can hurt when virtualized without hardware support -- whereas > >> + * mtmsr can be paravirtualized. > > > > We can always paravirtualize RFI as well if it makes sense. > > I'm not sure that's possible. We thought about it a while back, but > IIRC the difficulty was not leaving a register clobbered.
Besides mtmsr is slow on real HW as well. Also paravirt as done today for complex instructions like mtmsr is racy :-) (I already had a chat about that with Alex a while back, we might want to re-consider what kind of fix can be done at some point). Cheers, Ben. _______________________________________________ Linuxppc-dev mailing list [email protected] https://lists.ozlabs.org/listinfo/linuxppc-dev
