• Andi Kleen's avatar
    [PATCH] x86_64: Allow to run main time keeping from the local APIC interrupt · 73dea47f
    Andi Kleen authored
    Another piece from the no-idle-tick patch.
    
    This can be enabled with the "apicmaintimer" option.
    
    This is mainly useful when the PIT/HPET interrupt is unreliable.
    Note there are some systems that are known to stop the APIC
    timer in C3. For those it will never work, but this case
    should be automatically detected.
    
    It also only works with PM timer right now. When HPET is used
    the way the main timer handler computes the delay doesn't work.
    
    It should be a bit more efficient because there is one less
    regular interrupt to process on the boot processor.
    
    Requires earlier bugfix from Venkatesh
    Signed-off-by: default avatarAndi Kleen <ak@suse.de>
    Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
    73dea47f
apic.c 27.6 KB