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Peter Zijlstra 8e7fbcbc22 sched: Remove stale power aware scheduling remnants and dysfunctional knobs 
It's been broken forever (i.e. it's not scheduling in a power
aware fashion), as reported by Suresh and others sending
patches, and nobody cares enough to fix it properly ...
so remove it to make space free for something better.

There's various problems with the code as it stands today, first
and foremost the user interface which is bound to topology
levels and has multiple values per level. This results in a
state explosion which the administrator or distro needs to
master and almost nobody does.

Furthermore large configuration state spaces aren't good, it
means the thing doesn't just work right because it's either
under so many impossibe to meet constraints, or even if
there's an achievable state workloads have to be aware of
it precisely and can never meet it for dynamic workloads.

So pushing this kind of decision to user-space was a bad idea
even with a single knob - it's exponentially worse with knobs
on every node of the topology.

There is a proposal to replace the user interface with a single
3 state knob:

 sched_balance_policy := { performance, power, auto }

where 'auto' would be the preferred default which looks at things
like Battery/AC mode and possible cpufreq state or whatever the hw
exposes to show us power use expectations - but there's been no
progress on it in the past many months.

Aside from that, the actual implementation of the various knobs
is known to be broken. There have been sporadic attempts at
fixing things but these always stop short of reaching a mergable
state.

Therefore this wholesale removal with the hopes of spurring
people who care to come forward once again and work on a
coherent replacement.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/1326104915.2442.53.camel@twins
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-05-17 13:48:56 +02:00
..
ABI sched: Remove stale power aware scheduling remnants and dysfunctional knobs 2012-05-17 13:48:56 +02:00
accounting
acpi Update documentation for parameter *notrigger* in einj.txt 2012-03-30 03:30:19 -04:00
aoe Documentation: remove references to /etc/modprobe.conf 2012-03-30 16:03:15 -07:00
arm Documentation: Fix multiple typo in Documentation 2012-03-07 16:08:24 +01:00
auxdisplay
backlight backlight: new backlight driver for LP855x devices 2012-03-23 16:58:33 -07:00
blackfin
block Documentation: drop as block elevator reference in switching-sched.txt 2011-11-04 12:01:48 -07:00
blockdev Documentation: remove references to /etc/modprobe.conf 2012-03-30 16:03:15 -07:00
cdrom
cgroups memcg: fix up documentation on global LRU 2012-04-12 13:12:11 -07:00
connector
console
cpu-freq Doc: cpufreq: Fix typo and outdated line 2011-11-08 10:23:29 +01:00
cpuidle cpuidle: add a sysfs entry to disable specific C state for debug purpose. 2012-03-30 01:52:58 -04:00
cris
crypto
development-process Documentation: Update stable address 2011-12-12 14:14:31 -08:00
device-mapper dm: add verity target 2012-03-28 18:43:38 +01:00
devicetree sound fixes for 3.4-rc6 2012-05-05 10:07:06 -07:00
DocBook Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media 2012-04-21 12:43:23 -07:00
driver-model Merge remote-tracking branches 'regulator/topic/devm' and 'regulator/topic/stub' into regulator-next 2012-03-18 21:38:28 +00:00
dvb [media] lmedm04 RS2000 Firmware details 2012-03-19 14:55:55 -03:00
early-userspace
EDID drm: allow loading an EDID as firmware to override broken monitor 2012-03-20 10:09:28 +00:00
fault-injection fault-injection: update documentation with the mmc module param 2011-10-26 16:32:13 -04:00
fb Documentation: remove references to /etc/modprobe.conf 2012-03-30 16:03:15 -07:00
filesystems typo fix in Documentation/filesystems/vfs.txt 2012-04-09 01:39:24 -04:00
firmware_class
frv
hid
hwmon hwmon: (k10temp) Add support for AMD Trinity CPUs 2012-04-01 10:25:56 -07:00
i2c Documentation: remove references to /etc/modprobe.conf 2012-03-30 16:03:15 -07:00
i2o Documentation: Fix multiple typo in Documentation 2012-03-07 16:08:24 +01:00
ia64
ide Documentation: remove references to /etc/modprobe.conf 2012-03-30 16:03:15 -07:00
infiniband
input Documentation: input.txt: clarify mousedev 'cat' command syntax 2012-03-30 16:03:15 -07:00
ioctl Merge branch 'for-next' of git://gitorious.org/kernel-hsi/kernel-hsi 2012-04-02 09:50:40 -07:00
isdn Documentation: remove references to /etc/modprobe.conf 2012-03-30 16:03:15 -07:00
ja_JP
kbuild Documentation: mention scripts/diffconfig tool 2012-03-30 16:03:15 -07:00
kdump [S390] Add s390x description to Documentation/kdump/kdump.txt 2011-12-27 11:27:13 +01:00
ko_KR driver-core: documentation: fix up Greg's email address 2012-02-15 14:48:01 -08:00
laptops Documentation: remove references to /etc/modprobe.conf 2012-03-30 16:03:15 -07:00
leds drivers/leds/leds-lp5521.c: support led pattern data 2012-03-23 16:58:34 -07:00
m68k
make
mips
misc-devices
mmc mmc: core: Fixup delayed work clock gating patch 2012-01-11 23:58:43 -05:00
mn10300
mtd
namespaces
netlabel
networking tcp: change tcp_adv_win_scale and tcp_rmem[2] 2012-05-02 21:08:58 -04:00
nfc
parisc
PCI
pcmcia
power PM / Freezer / Docs: Update documentation about freezing of tasks 2012-04-29 22:29:30 +02:00
powerpc Documentation/powerpc/mpc52xx.txt: Checkpatch cleanup 2012-03-18 23:59:34 +01:00
pps
prctl
pti
ptp
rapidio RapidIO: documentation update 2011-11-02 16:07:02 -07:00
RCU rcu: Call out dangers of expedited RCU primitives 2012-02-21 09:06:08 -08:00
s390 Documentation: remove references to /etc/modprobe.conf 2012-03-30 16:03:15 -07:00
scheduler sched: Remove stale power aware scheduling remnants and dysfunctional knobs 2012-05-17 13:48:56 +02:00
scsi SCSI updates on 20120331 2012-03-31 13:31:23 -07:00
security keys: update the documentation with info about "logon" keys 2012-04-25 12:46:50 -04:00
serial Documentation: remove references to /etc/modprobe.conf 2012-03-30 16:03:15 -07:00
sh
sound ALSA: hda/realtek - Add a few ALC882 model strings back 2012-04-11 14:10:57 +02:00
sparc
spi spi: create a message queueing infrastructure 2012-03-07 19:19:48 -07:00
sysctl Documentation: add missing tainted bits to Documentation/sysctl/kernel.txt 2012-02-06 16:29:19 -08:00
target Documentation: Fix typo in tcm_mod_builder.py 2012-02-10 09:52:18 +01:00
telephony
thermal thermal: Rename generate_netlink_event 2012-01-23 03:15:25 -05:00
timers
trace Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2012-03-20 21:12:50 -07:00
usb USB documentation: explain lifetime rules for unlinking URBs 2012-04-06 13:54:00 -07:00
vDSO
video4linux Documentation: remove references to /etc/modprobe.conf 2012-03-30 16:03:15 -07:00
virtual Merge branch 'kvm-updates/3.4' of git://git.kernel.org/pub/scm/virt/kvm/kvm 2012-03-28 14:35:31 -07:00
vm mm: move hugepage test examples to tools/testing/selftests/vm 2012-03-28 17:14:37 -07:00
w1
watchdog watchdog: Add support for WDIOC_GETTIMELEFT IOCTL in watchdog core 2012-03-27 20:15:37 +02:00
wimax
x86
zh_CN Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2012-03-20 21:04:47 -07:00
.gitignore
00-INDEX crc32: move long comment about crc32 fundamentals to Documentation/ 2012-03-23 16:58:37 -07:00
applying-patches.txt
atomic_ops.txt doc: Add load/store guarantees to Documentation/atomic-ops.txt 2011-12-11 10:31:58 -08:00
bad_memory.txt
basic_profiling.txt
binfmt_misc.txt
braille-console.txt
bt8xxgpio.txt
btmrvl.txt
BUG-HUNTING
bus-virt-phys-mapping.txt
cachetlb.txt
Changes
circular-buffers.txt
clk.txt Documentation: common clk API 2012-03-16 20:35:01 +00:00
coccinelle.txt coccinelle.txt: update documentation to include M= option 2012-01-14 22:25:56 +01:00
CodingStyle Documentation: CodingStyle: add inline assembly guidelines 2012-03-30 16:03:15 -07:00
cpu-hotplug.txt documentation: remove references to cpu_*_map. 2012-03-29 15:38:31 +10:30
cpu-load.txt
cputopology.txt
crc32.txt crc32: move long comment about crc32 fundamentals to Documentation/ 2012-03-23 16:58:37 -07:00
dcdbas.txt
debugging-modules.txt
debugging-via-ohci1394.txt
dell_rbu.txt
devices.txt vhost-net: add module alias (v2.1) 2012-01-13 10:12:23 -08:00
digsig.txt crypto: digital signature verification support 2011-11-09 12:10:37 +02:00
DMA-API-HOWTO.txt
DMA-API.txt include/linux/dma-mapping.h: add dma_zalloc_coherent() 2011-11-02 16:07:02 -07:00
DMA-attributes.txt common: DMA-mapping: add NON-CONSISTENT attribute 2012-03-28 16:36:44 +02:00
dma-buf-sharing.txt dma-buf: document fd flags and O_CLOEXEC requirement 2012-03-26 11:33:22 +05:30
DMA-ISA-LPC.txt
dmaengine.txt Documentation: Fix multiple typo in Documentation 2012-03-07 16:08:24 +01:00
dontdiff Documentation: remove 'mach' from dontdiff file 2012-03-30 16:03:15 -07:00
dynamic-debug-howto.txt dynamic_debug: process multiple debug-queries on a line 2012-01-24 12:50:36 -08:00
edac.txt EDAC: Correct scrub rate API 2012-03-19 12:03:58 +01:00
eisa.txt
email-clients.txt
feature-removal-schedule.txt Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-04-12 15:16:26 -07:00
flexible-arrays.txt
futex-requeue-pi.txt
gcov.txt
gpio.txt Documentation/gpio.txt: Explain expected pinctrl interaction 2012-03-12 11:27:07 -06:00
highuid.txt
HOWTO Documentation: Update stable address 2011-12-12 14:14:31 -08:00
hw_random.txt
hwspinlock.txt
init.txt
initrd.txt
intel_txt.txt
Intel-IOMMU.txt
io_ordering.txt
io-mapping.txt
iostats.txt
IPMI.txt
IRQ-affinity.txt
IRQ-domain.txt irq_domain: add documentation and MAINTAINERS entry. 2012-02-14 14:06:47 -07:00
IRQ.txt
irqflags-tracing.txt
isapnp.txt
java.txt
kernel-doc-nano-HOWTO.txt
kernel-docs.txt
kernel-parameters.txt Merge branch 'for-3.4' of git://linux-nfs.org/~bfields/linux 2012-03-29 14:53:25 -07:00
kmemcheck.txt
kmemleak.txt kmemleak: Handle percpu memory allocation 2011-12-02 16:12:42 +00:00
kobject.txt driver-core: documentation: fix up Greg's email address 2012-02-15 14:48:01 -08:00
kprobes.txt
kref.txt
ldm.txt
local_ops.txt
lockdep-design.txt lockdep: Update documentation for lock-class leak detection 2011-12-11 10:31:23 -08:00
lockstat.txt
lockup-watchdogs.txt watchdog: Update documentation 2012-02-11 15:11:28 +01:00
logo.gif
logo.txt
magic-number.txt drivers/net: fix up stale paths from driver reorg 2012-01-30 12:54:40 -05:00
Makefile mm: move hugepage test examples to tools/testing/selftests/vm 2012-03-28 17:14:37 -07:00
ManagementStyle
mca.txt
md.txt md: create externally visible flags for supporting hot-replace. 2011-12-23 10:17:51 +11:00
media-framework.txt
memory-barriers.txt
memory-hotplug.txt
memory.txt
mono.txt Documentation: remove references to /etc/modprobe.conf 2012-03-30 16:03:15 -07:00
mutex-design.txt
nommu-mmap.txt
numastat.txt Doc: Update numastat.txt 2012-02-28 16:05:06 +01:00
oops-tracing.txt module,bug: Add TAINT_OOT_MODULE flag for modules not built in-tree 2011-11-07 07:54:42 +10:30
padata.txt
parport-lowlevel.txt
parport.txt Documentation: remove references to /etc/modprobe.conf 2012-03-30 16:03:15 -07:00
pi-futex.txt
pinctrl.txt pinctrl: enhance mapping table to support pin config operations 2012-03-05 11:25:11 +01:00
pnp.txt
preempt-locking.txt
printk-formats.txt
prio_tree.txt
ramoops.txt
rbtree.txt
remoteproc.txt remoteproc: remove the single rpmsg vdev limitation 2012-03-06 19:14:12 +02:00
rfkill.txt
robust-futex-ABI.txt
robust-futexes.txt
rpmsg.txt rpmsg: add virtio-based remote processor messaging bus 2012-02-08 22:53:58 +02:00
rt-mutex-design.txt
rt-mutex.txt
rtc.txt
SAK.txt
SecurityBugs
serial-console.txt
sgi-ioc4.txt
sgi-visws.txt
SM501.txt
sparse.txt
spinlocks.txt
stable_api_nonsense.txt
stable_kernel_rules.txt stable: update documentation to ask for kernel version 2012-01-24 10:50:22 -08:00
static-keys.txt static keys: Add docs better explaining the whole 'struct static_key' mechanism 2012-02-24 09:12:19 +01:00
SubmitChecklist
SubmittingDrivers
SubmittingPatches
svga.txt
sysfs-rules.txt
sysrq.txt Documentation: sysrq: Crutcher Dunnavant is unavailable 2012-03-30 16:03:15 -07:00
unaligned-memory-access.txt
unicode.txt
unshare.txt
VGA-softcursor.txt
vgaarbiter.txt misc latin1 to utf8 conversions 2012-01-02 13:04:55 +01:00
video-output.txt
volatile-considered-harmful.txt
workqueue.txt
xz.txt
zorro.txt