On Tue, 2010-06-22 at 17:29 +0800, Zhang, Yanmin wrote: > On Tue, 2010-06-22 at 10:00 +0200, Jes Sorensen wrote: > > On 06/22/10 09:55, Peter Zijlstra wrote: > > > On Tue, 2010-06-22 at 15:47 +0800, Zhang, Yanmin wrote: > > >> Besides the para virt perf interface, I'm also considering the direct > > >> exposition > > >> of PMU hardware to guest os. > > > > > > NAK NAK NAK NAK, we've been over that, its not going to happen, full > > > stop! > > > > > > Use MSR read/write traps and host perf to emulate the hardware. In some > > > cases we could allow the reads without trap but that's a later > > > optimization. > > > > I believe whats meant here is a PMU compatible interface which is > > partially emulated. Not a handover of the PMU. > Right. We need capture all write to PMU MSR and allows guest os to read MSR > directly.
That latter is not possible, only in a subset of cases can you allow that read. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
