Messages in this thread | | | Subject | Re: 2.6.19-rc4-mm1: noidlehz problems | From | Arjan van de Ven <> | Date | Wed, 01 Nov 2006 14:02:57 +0100 |
| |
On Wed, 2006-11-01 at 13:23 +0100, Pavel Machek wrote: > Hi! > > First, it would be nice if we had someone listed as a maintainer of > noidlehz stuff... > > Then... I'm getting strange messages from noidlehz each time I > unplug/replug AC power (perhaps due to interrupt latency?).
there probably is a different story going on. When you unplug/replug AC power, several bioses change the meaning of the software C-states in your system. (there is a mapping between software visible C states and the hardware C-states)
In some (hardware) C-states, the local apic timer stops (as does the TSC), while in others it keeps running. If you change from AC to battery, the bios can change the meaning of a software C-state from one where local apic timer keeps going to one where it stops. This obviously upsets the hrtimers/tickless code since that uses local apic timer for event generation....
-- if you want to mail me at work (you don't), use arjan (at) linux.intel.com Test the interaction between Linux and your BIOS via http://www.linuxfirmwarekit.org
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |