lkml.org 
[lkml]   [2006]   [Oct]   [23]   [last100]   RSS Feed
Views: [more markup]  [less markup]  [headers]  [forward] 
 
Messages in this thread
/
DateSun, 22 Oct 2006 23:17:23 -0700
Fromyhlu <>
SubjectRe: [PATCH 2/2] x86_64 irq: Only look at per_cpu data for online cpus.
On 10/22/06, Eric W. Biederman <ebiederm@xmission.com> wrote:
>
> When I generalized __assign_irq_vector I failed to pay attention
> to what happens when you access a per cpu data structure for
> a cpu that is not online.   It is an undefined case making any
> code that does it have undefined behavior as well.
>
> The code still needs to be able to allocate a vector across cpus
> that are not online to properly handle combinations like lowest
> priority interrupt delivery and cpu_hotplug.  Not that we can do
> that today but the infrastructure shouldn't prevent it.
>
> So this patch updates the places where we touch per cpu data
> to only touch online cpus, it makes cpu vector allocation
> an atomic operation with respect to cpu hotplug, and it updates
> the cpu start code to properly initialize vector_irq so we
> don't have inconsistencies.
>
> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>

Acked-by: Yinghai Lu <yinghai.lu@amd.com>
-
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/

\
 
 \ /
  Last update: 2006-10-23 08:19    [from the cache]
©2003-2008