Messages in this thread | | | Subject | Re: [patch] i386/x86_64: smp_call_function locking inconsistency | From | Jan Glauber <> | Date | Fri, 09 Feb 2007 13:57:18 +0100 |
| |
On Fri, 2007-02-09 at 09:42 +0100, Heiko Carstens wrote: > I just want to avoid that s390 has different semantics for > smp_call_functiom*() than any other architecture. But then again it > will probably not hurt since we allow more. > Another thing that comes into my mind is smp_call_function together > with cpu hotplug. Who is responsible that preemption and with that > cpu hotplug is disabled? > Is it the caller or smp_call_function itself?
I think the caller must disable preemption since smp_call_function() means "do something on all but the current cpu". If the preempt_disable would happen only in smp_call_function() it could already be running on a different cpu, which is not what the caller wants.
If preemption must be disabled before smp_call_function() we should have the same semantics for all smp_call_function_* variants.
Jan
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |