19 Oct
2012
19 Oct
'12
3:41 p.m.
On 10/19/2012 03:02 PM, Fons Adriaensen wrote:
Hello all,
My ex-collegues at Alcatel are screaming for help. They want to
run an app (as root, debatable but that's another story) using
SCHED_FIFO threads on an openSuSE 11.4 system.
Using the 'default' kernel (which has CONFIG_PREEMPT not set),
this works. Using the 'desktop' kernel (CONFIG_PREEMPT=y) they get
an EPERM when trying to start a RT thread, even as root.
As I haven't used SuSE for ages, has anyone an idea of what is
happening here ?
I never used openSuse. and "does not work" is too little info for an
educated guess. So just a few shots in the dark:
/proc/sys/kernel/sched_rt_period_us
/proc/sys/kernel/sched_rt_runtime_us
kernel.sched_rt_runtime_us globally limits realtime
scheduling time.
Maybe cgroups are getting in the way? or possibly grsecurity.
Since it works with the vanilla kernel, PAM and
/etc/security/limits.conf etc do not seem to be the cause, but hey: It
could be related to cgroups, sessions and not su'ing properly.
ciao,
robin