Re: [Lse-tech] [PATCH] cpusets+hotplug+preepmt broken

Paul Jackson
2005-05-11T20:46:54Z

Nathan asked:
> Won't holding cpuset_sem while calling cpuset_cpus_allowed cause a
> deadlock?

It definitely would, which is why Dinakar's patch both added a call to
get cpuset_sem earlier in the hot unplug code, as well as removed the
call to get cpuset_sem that was inside the cpuset_cpus_allowed code (as
well as modified the other caller of cpuset_cpus_allowed, the
sched_setaffinity code, to explicitly get cpuset_sem before calling
cpuset_cpus_allowed, since that call no longer acquired cpuset_sem on
its own.

--
I won't rest till it's the best ...
Programmer, Linux Scalability
Paul Jackson <pj@engr.sgi.com> 1.650.933.1373, 1.925.600.0401