> What's the benefit of doing so - and why has not it been done before?
you're mixing up 2 concepts:
1) is for "what time is it now", and acpi_pm is useful for that, as are
several other things such as rdtsc
2) is for "I need THIS to happen X miliseconds from now". acpi_pm is not
useful for that, nor is rdtsc.
some can be used for both (PIT), but on a concept level the uses are
independent. The advantage of local apic over PIT is that local apic is
cheap to do "one shot" future events with, while the PIT will tick
periodic at a fixed frequency. With tickless idle.. that's not what you
if you want to mail me at work (you don't), use arjan (at) linux.intel.com
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