Re: [PATCH -rt 5/5] slub: -rt port

Peter Zijlstra
2007-07-14T19:50:26Z

On Sat, 2007-07-14 at 23:38 +0400, Oleg Nesterov wrote:
> On 07/14, Peter Zijlstra wrote:

> > Yeah, the function I copied this from: schedule_on_each_cpu() has a
> > comment to that effect.
>
> Just in case, schedule_on_each_cpu() ptotects cpu_online_map with
> preempt_disable(), its problem is quite different.

I was schedule_on_each_cpu_wq() I copied, and that does not disable
preemption. Also, I'm failing to see how schedule_on_each_cpu() could
work with -rt, since __queue_work() takes a regular spinlock.

> > Any ideas on how to solve this?
>
> Perhaps slab_cpuup_callback() can take flush_slab_mutex too, in that
> case cpu_online_map will be stable under flush_slab_mutex.

Right, I'll give that a try.