kernel/cpu.c: create a CPU_STARTING cpu_chain notifier

Right now, there is no notifier that is called on a new cpu, before the new
cpu begins processing interrupts/softirqs.
Various kernel function would need that notification, e.g. kvm works around
by calling smp_call_function_single(), rcu polls cpu_online_map.

The patch adds a CPU_STARTING notification. It also adds a helper function
that sends the message to all cpu_chain handlers.

Tested on x86-64.
All other archs are untested. Especially on sparc, I'm not sure if I got
it right.

Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Manfred Spraul 2008-09-07 16:57:22 +02:00 committed by Ingo Molnar
parent 7686ad5606
commit e545a6140b
17 changed files with 51 additions and 1 deletions

View file

@ -498,6 +498,8 @@ static void __init smp_online(void)
{
int cpu_id = smp_processor_id();
notify_cpu_starting(cpu_id);
local_irq_enable();
/* Get our bogomips. */