Re: Plumbers: Tweaking scheduler policy micro-conf RFP

[Ingo Molnar <mingo@kernel.org>]

* Peter Zijlstra <peterz@infradead.org> wrote:

> On Sat, 2012-05-19 at 10:08 -0700, Linus Torvalds wrote:
> > And I
> > *do* know that the real world simply isn't simple enough that we could
> > ever do a perfect job, so don't even try - instead aim for
> > "understandable, maintainable, and gets the main issues roughly
> > right". 
> 
> I think we're in violent agreement on many points and most of 
> this is based on a mis-understanding. I've argued for exactly 
> this many times.

it's these pending commits in tip:sched/core:

8e7fbcbc22c1 sched: Remove stale power aware scheduling remnants and dysfunctional knobs
fac536f7e492 Merge branch 'sched/urgent' into sched/core
13e099d2f77e sched/debug: Fix printing large integers on 32-bit platforms
e44bc5c5d00e sched/fair: Improve the ->group_imb logic
556061b00c9f sched/nohz: Fix rq->cpu_load[] calculations
870a0bb5d636 sched/numa: Don't scale the imbalance
04f733b4afac sched/fair: Revert sched-domain iteration breakage
316ad248307f sched/x86: Rewrite set_cpu_sibling_map()
dd7d8634e619 sched/numa: Fix the new NUMA topology bits
cb83b629bae0 sched/numa: Rewrite the CONFIG_NUMA sched domain support
bd939f45da24 sched/fair: Propagate 'struct lb_env' usage into find_busiest_group
0ce90475dcdb sched/fair: Add some serialization to the sched_domain load-balance walk
c22402a2f76e sched/fair: Let minimally loaded cpu balance the group
c82513e51355 sched: Change rq->nr_running to unsigned int
ad7687dde878 x86/numa: Check for nonsensical topologies on real hw as well
0acbb440f063 x86/numa: Hard partition cpu topology masks on node boundaries
94c0dd3278dd x86/numa: Allow specifying node_distance() for numa=fake
19209bbb8612 x86/sched: Make mwait_usable() heed to "idle=" kernel parameters properly
489a71b029cd sched: Update documentation and comments

the result of these commits is:

 24 files changed, 417 insertions(+), 975 deletions(-)

Most of the linecount win is due to the removal of the 
dysfunctional power scheduling - but even without that commit 
it's a simplification:

 15 files changed, 415 insertions(+), 481 deletions(-)

while it lifts the historic limitations of the sched-domains 
approach and makes the code a whole lot more logical.

Nevertheless I'll wait for Linus to confirm that he agrees 
violently as well, before sending these bits ;-)

Thanks,

	Ingo