Re: [PATCH] cpuset and sched domains: sched_load_balance flag

Paul Jackson
2007-10-03T17:46:51Z

Nick wrote:
> So if a new pdflush is spawned, it get's moved to some cpuset? That
> probably isn't something these realtime systems want to do (ie. the
> non-realtime portion probably doesn't want to have any sort of scheduler
> or even worry about cpusets at all).

No - the new pdflush is put in the same cpuset as its parent, with a
patch that I sent in early this year. See the following code in
mm/pdflush.c:

/*
* Some configs put our parent kthread in a limited cpuset,
* which kthread() overrides, forcing cpus_allowed == CPU_MASK_ALL.
* Our needs are more modest - cut back to our cpusets cpus_allowed.
* This is needed as pdflush's are dynamically created and destroyed.
* The boottime pdflush's are easily placed w/o these 2 lines.
*/
cpus_allowed = cpuset_cpus_allowed(current);
set_cpus_allowed(current, cpus_allowed);

return __pdflush(&my_work);

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