how to get current cpu id

Matthias Lange matthias.lange at kernkonzept.com
Thu May 15 08:03:26 CEST 2014


On Wed, May 14, 2014 at 07:27:16PM -0400, Yuxin Ren wrote:
> Thank you for your reply.
> I understand you. But I still have a question.
> How can I know when the thread finish its migration?
> In my scenario, master thread creates children threads and then migrate
> then to other cores.
> It waits until all children finish migration.
> The problem is how does master thread guarantee all children finish
> migration.

You can have a look at the migrate example in examples/sys/migrate. Migration
is synchronous, so when the call to the scheduler proxy has finished the
thread has been migrated.

Matthias.

> 
> Thank you.
> 
> 
> On Wed, May 14, 2014 at 7:14 PM, Adam Lackorzynski <
> adam at os.inf.tu-dresden.de> wrote:
> 
> > On Tue May 13, 2014 at 17:05:34 -0800, Yuxin Ren wrote:
> > > How can I get the id of cpu(core) the current thread is running on?
> >
> > The system does not do migrate threads between CPUs on its own, so your
> > program is running on CPU0. And from that point (in a simple scenario)
> > programs control themselves where they migrate to, so they know where
> > they are running on.
> >
> >
> > Adam
> > --
> > Adam                 adam at os.inf.tu-dresden.de
> >   Lackorzynski         http://os.inf.tu-dresden.de/~adam/
> >
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> >

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Matthias Lange, matthias.lange at kernkonzept.com, +49 - 351 - 41 88 86 14

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