On 16/2/07 17:46, "Jeremy Fitzhardinge" <jeremy at goop.org> wrote: > Keir Fraser wrote: >> This initial patchset does not include save/restore support anyway, so in >> fact it would be consistent to have CONFIG_PREEMPT configurable. I'm sure >> that we are going to have some nasty bugs to fix up as a result, but we >> can't fix them until we find them! Then we can convert our save/restore code >> to use the freezer before submitting it for inclusion. > OK. So that makes the only config restriction the 100Hz ticks. We can extend the Xen timer interface quite easily and get rid of this one too. In fact it doesn't *much* matter if the CONFIG_HZ differs from the Xen ticker rate -- we modified the Linux timer ISR to handle timer interrupts at arbitrary times already. The only drawback is that jiffies updates in burts if CONFIG_HZ is higher than the actual tick rate, and this can affect some calibration constants and cause Linux to print out some weird values at start-of-day. -- Keir
