Messages in this thread | | | Date | Wed, 07 Sep 2005 12:14:55 -0400 | From | Bill Davidsen <> | Subject | Re: [PATCH 1/3] dynticks - implement no idle hz for x86 |
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Srivatsa Vaddagiri wrote: > On Sun, Sep 04, 2005 at 10:48:13PM -0700, Nishanth Aravamudan wrote: > >>Admittedly, I don't think SMP ARM has been around all that long? Maybe >>the existing code just has not been extended. > > > Yeah, maybe ARM never cared for SMP. But we do care :) > > >>I'm not sure on this. It's going to be NULL for other architectures, or >>end up being called by the reprogram() call for the last CPU to go idle, >>right (presuming there isn't a separate TOD source, like in x86). I >>think it is better to be in the reprogram() interface. > > > Non-x86 could have it set to NULL, in which case it doesn't get called. > (I know the current code does not take care of this situation). > But having an explicit 'all_cpus_idle' interface may be good, since > Tony talked of idling some devices when all CPUs are idle. So it > probably has non-x86/PIT uses too.
If this is intended to reduce power, and it originally came from that root, then this is the time to put in a hook for transitions to<=>from the all-idle state. Various arch may have things other than the PIT which should (or at least can) be stopped, and which need to be restarted.
-- -bill davidsen (davidsen@tmr.com) "The secret to procrastination is to put things off until the last possible moment - but no longer" -me - 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/
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