Messages in this thread | | | From | "limp" <> | Subject | Where system interrupts get disabled at LAPIC timer handler execution? | Date | Fri, 16 Jul 2010 10:25:32 +0100 |
| |
Dear all,
I am trying to demystify what happens when the kernel has configured to use LAPIC timer as its timer and I've ran into some problems/questions.
AFAIK, when a LAPIC timer interrupt occurs, the assembly wrapper at enrty_32.s jumps the execution at smp_apic_timer_interrupt(). At the beginning of this function, I've checked to see if interrupts are enabled or not using irqs_disabled() and I found out that they are disabled.
The problem is that I can't find where Linux disables interrupts before calling smp_apic_timer_interrupt(). The only place this could be done is in the assembly wrapper but I can't really find it.
Does the processor disables interrupts by default when a LAPIC timer interrupt occurs?
Any help will be much appreciated.
Thanks in advance.
John.
| |