From 73dea47faeb96d54a984b9d7f4de564816966354 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Fri, 3 Feb 2006 21:50:50 +0100 Subject: [PATCH] x86_64: Allow to run main time keeping from the local APIC interrupt 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: Andi Kleen Signed-off-by: Linus Torvalds --- include/asm-x86_64/apic.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/asm-x86_64/apic.h') diff --git a/include/asm-x86_64/apic.h b/include/asm-x86_64/apic.h index 4f6a4dc455b..bdbd8935612 100644 --- a/include/asm-x86_64/apic.h +++ b/include/asm-x86_64/apic.h @@ -17,6 +17,7 @@ #define APIC_DEBUG 2 extern int apic_verbosity; +extern int apic_runs_main_timer; /* * Define the default level of output to be very little -- cgit v1.2.3