On Tue, 2007-02-27 at 02:38 -0500, Mathieu Desnoyers wrote: > > I am concerned about the automatic fallback to the PIT when no other > clock source is available. A clocksource read would be atomic when TSC > or HPET are available, but would fall back on PIT otherwise. There > should be some way to specify that a caller is only interested in atomic > clock sources (if none are available, the call should simply return an > error, or 0). > > I still think that an RCU style update mechanism would be a good way to > fix the current clocksource read issue. Another, slower and non NMI > safe way to do this would be with a read seqlock and with IRQ disabling.
I'm not sure what you mean by using the RCU, but the pit clocksource does disable interrupts with a spin_lock_irqsave(). Daniel - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
