On Mon, Jun 27, 2016 at 01:26:54PM +0200, Paolo Bonzini wrote: > > > On 20/06/2016 18:55, Roman Kagan wrote: > > > Note that even in the (faked) case of PVCLOCK_TSC_STABLE_BIT unset, when > > > pvclock_clocksource_read() tries to monotonize the clock using basically > > > the same technique as the testcase uses, it still fails the global > > > monotonicity test. > > > > I've finally realized the obvious "how I screwed it all up": the > > standard pattern is to read the clock and compare to other vCPUs / > > update the shared value in a single critical section. So please > > disregard my patches to the tests, per-cpu counters are of little > > interest here. > > Actually aren't per-cpu counters used by the vDSO? Yes they are, but the vDSO code explicitly protects against warps as this is considered normal situation. Roman. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
