linux/drivers
Arjan van de Ven 1f85f87d4f cpuidle: add a repeating pattern detector to the menu governor
Currently, the menu governor uses the (corrected) next timer as key item
for predicting the idle duration.

It turns out that there are specific cases where this breaks down: There
are cases where we have a very repetitive pattern of idle durations, where
the idle period is pretty much the same, for reasons completely unrelated
to the next timer event.  Examples of such repeating patterns are network
loads with irq mitigation, the mouse moving but in theory also the wifi
beacons.

This patch adds a relatively simple detector for such repeating patterns,
where the standard deviation of the last 8 idle periods is compared to a
threshold.

With this extra predictor in place, measurements show that the DECAY
factor can now be increased (the decaying average will now decay slower)
to get an even more stable result.

[arjan@infradead.org: fix bug identified by Frank]
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Corrado Zoccolo <czoccolo@gmail.com>
Cc: Frank Rowand <frank.rowand@am.sony.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 08:07:02 -07:00
..
accessibility
acpi sysfs: add struct file* to bin_attr callbacks 2010-05-21 09:37:31 -07:00
amba
ata Merge remote branch 'origin' into secretlab/next-devicetree 2010-05-22 00:36:56 -06:00
atm Merge remote branch 'origin' into secretlab/next-devicetree 2010-05-22 00:36:56 -06:00
auxdisplay
base mm: compaction: add /sys trigger for per-node memory compaction 2010-05-25 08:06:59 -07:00
block Merge remote branch 'origin' into secretlab/next-devicetree 2010-05-22 00:36:56 -06:00
bluetooth Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6 2010-05-20 21:04:44 -07:00
cdrom of: Always use 'struct device.of_node' to get device node pointer. 2010-05-18 16:10:44 -06:00
char Merge branch 'bkl/ioctl' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing 2010-05-24 08:01:10 -07:00
clocksource Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2010-05-19 17:10:57 -07:00
connector
cpufreq Merge branch 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2010-05-18 08:49:13 -07:00
cpuidle cpuidle: add a repeating pattern detector to the menu governor 2010-05-25 08:07:02 -07:00
crypto Merge remote branch 'origin' into secretlab/next-devicetree 2010-05-22 00:36:56 -06:00
dca
dio
dma Merge git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6 2010-05-24 07:58:28 -07:00
edac Merge remote branch 'origin' into secretlab/next-devicetree 2010-05-22 00:36:56 -06:00
eisa
firewire Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2010-05-20 09:20:59 -07:00
firmware sysfs: add struct file* to bin_attr callbacks 2010-05-21 09:37:31 -07:00
gpio Merge remote branch 'origin' into secretlab/next-devicetree 2010-05-22 00:36:56 -06:00
gpu Merge branch 'drm-for-2.6.35' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6 2010-05-21 11:14:52 -07:00
hid Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid 2010-05-21 10:51:03 -07:00
hwmon Merge branch 'bkl/ioctl' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing 2010-05-24 08:01:10 -07:00
i2c Merge remote branch 'origin' into secretlab/next-devicetree 2010-05-22 00:36:56 -06:00
ide Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/ide-2.6 2010-05-24 08:05:29 -07:00
idle
ieee1394
ieee802154
infiniband Merge remote branch 'origin' into secretlab/next-devicetree 2010-05-22 00:36:56 -06:00
input Merge branch 'bkl/ioctl' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing 2010-05-24 08:01:10 -07:00
isdn Merge branch 'bkl/ioctl' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing 2010-05-24 08:01:10 -07:00
leds of: Remove duplicate fields from of_platform_driver 2010-05-22 00:10:40 -06:00
lguest
macintosh Merge branch 'bkl/ioctl' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing 2010-05-24 08:01:10 -07:00
mca
md Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 2010-05-21 19:37:45 -07:00
media Merge branch 'bkl/ioctl' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing 2010-05-24 08:01:10 -07:00
memstick
message fusion: fix kernel-doc notation 2010-05-24 07:31:20 -07:00
mfd sh: allow platforms to specify SD-card supported voltages 2010-05-22 17:05:22 +09:00
misc Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2010-05-21 11:17:05 -07:00
mmc Merge git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6 2010-05-24 07:58:28 -07:00
mtd Merge branch 'bkl/ioctl' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing 2010-05-24 08:01:10 -07:00
net Revert "ath9k: Group Key fix for VAPs" 2010-05-24 07:45:43 -07:00
nubus
of Merge remote branch 'origin' into secretlab/next-devicetree 2010-05-22 00:36:56 -06:00
oprofile
parisc
parport Merge remote branch 'origin' into secretlab/next-devicetree 2010-05-22 00:36:56 -06:00
pci Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6 2010-05-21 18:58:52 -07:00
pcmcia Merge branch 'bkl/ioctl' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing 2010-05-24 08:01:10 -07:00
platform Move N014, N051 and CR620 dmi information to load scm dmi table 2010-05-20 10:16:13 -04:00
pnp
power Merge git://git.infradead.org/battery-2.6 2010-05-24 08:00:13 -07:00
pps
ps3
rapidio sysfs: add struct file* to bin_attr callbacks 2010-05-21 09:37:31 -07:00
regulator Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2010-05-20 09:20:59 -07:00
rtc Merge branch 'bkl/ioctl' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing 2010-05-24 08:01:10 -07:00
s390 sysfs: add struct file* to bin_attr callbacks 2010-05-21 09:37:31 -07:00
sbus Merge branch 'bkl/ioctl' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing 2010-05-24 08:01:10 -07:00
scsi Merge branch 'bkl/ioctl' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing 2010-05-24 08:01:10 -07:00
serial m68knommu: fix broken use of BUAD_TABLE_SIZE in 68328serial driver 2010-05-25 08:07:02 -07:00
sfi
sh
sn
spi Merge remote branch 'origin' into secretlab/next-devicetree 2010-05-22 00:36:56 -06:00
ssb Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6 2010-05-20 21:04:44 -07:00
staging Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging-2.6 2010-05-21 15:26:46 -07:00
tc
telephony
thermal
uio
usb Merge branch 'bkl/ioctl' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing 2010-05-24 08:01:10 -07:00
uwb
vhost
video Merge remote branch 'origin' into secretlab/next-devicetree 2010-05-22 00:36:56 -06:00
virtio Merge branch 'virtio' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus 2010-05-21 17:22:52 -07:00
vlynq
w1 sysfs: add struct file* to bin_attr callbacks 2010-05-21 09:37:31 -07:00
watchdog Merge remote branch 'origin' into secretlab/next-devicetree 2010-05-22 00:36:56 -06:00
xen
zorro sysfs: add struct file* to bin_attr callbacks 2010-05-21 09:37:31 -07:00
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