top command shows 100% irq

[Rabin Vincent]

On Mon, Apr 2, 2012 at 11:16, naveen yadav <yad.naveen at gmail.com> wrote:
>> So it seams to me when struct clock_event_device *evt =
>> &__get_cpu_var(percpu_clockevent); is in irq_enter() function, this
>> leads  100% irq.
>> what may be issue.

The problem is that ipi_timer() is also called from do_local_timer()
on older kernels.  So if you backport this patch to an older kernel,
you need to additionally add the irq_enter() and irq_exit() calls
around the call to ipi_timer() in do_local_timer(), since the patch
moves them out of ipi_timer().

do_local_timer() doesn't exist on the kernel the patch was made for,
since the percpu irq rework removed it.