[arm-gnu] Problems with pthread on ARM/PXA270

Jamie Lokier jamie at shareable.org
Fri Sep 18 08:48:48 EDT 2009

Uwe Kleine-König wrote:
> On Thu, Sep 17, 2009 at 08:54:44AM +1000, James wrote:
> > Are you running with superuser privileges?  My manpage tells me that
> > SCHED_RR is only available if run with superuser privileges.
> Note that pthread_attr_setschedpolicy has a return value that tells you
> if the function was successful.

And that SCHED_RR has a time quantum returned by sched_rr_get_interval
which is not guaranteed to be small.  However, if it is a small time
and it's not switching that's a bug in either libc or the kernel.

Note that printf() does locking which may complicate things.  Try
opening separate outputs for each thread, or using write().

-- Jamie

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