[lkml]   [2009]   [Jan]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH 2/3] work_on_cpu: Use our own workqueue.
Ingo Molnar wrote:
> * Oleg Nesterov <> wrote:
>> But "[PATCH 1/3] work_on_cpu: dont try to get_online_cpus() in
>> work_on_cpu." removes get_online_cpus/put_online_cpus, this means the
>> work can run on the wrong CPU anyway. Or work_on_cpu() can hang forever
>> if CPU has already gone away before queue_work_on().
>> Confused.
> The idea was to require work_on_cpu() users to be CPU hotplug-safe. But
> ... Rusty pointed it out in the past that this might be fragile, and we
> could put back the get_online_cpus()/put_online_cpus() calls.
> Rusty, what do you think?
> Ingo

I believe that is the intention, in that the caller should insure that
the cpu does not go offline. But also as Rusty stated, the previous usages
of set_cpus_allowed did not always insure this, so it's at least not a

I'll put it on my todo list to check the references in tip/cpus4096 to see
where they stand on the get_online_cpus() issue.


 \ /
  Last update: 2009-01-27 00:05    [from the cache]
©2003-2014 Jasper Spaans. hosted at Digital Ocean