Johannes Weiner 3bbcbc8039 UPSTREAM: psi: make disabling/enabling easier for vendor kernels ... Mel Gorman reports a hackbench regression with psi that would prohibit shipping the suse kernel with it default-enabled, but he'd still like users to be able to opt in at little to no cost to others. With the current combination of CONFIG_PSI and the psi_disabled bool set from the commandline, this is a challenge. Do the following things to make it easier: 1. Add a config option CONFIG_PSI_DEFAULT_DISABLED that allows distros to enable CONFIG_PSI in their kernel but leave the feature disabled unless a user requests it at boot-time. To avoid double negatives, rename psi_disabled= to psi=. 2. Make psi_disabled a static branch to eliminate any branch costs when the feature is disabled. In terms of numbers before and after this patch, Mel says: : The following is a comparision using CONFIG_PSI=n as a baseline against : your patch and a vanilla kernel : : 4.20.0-rc4 4.20.0-rc4 4.20.0-rc4 : kconfigdisable-v1r1 vanilla psidisable-v1r1 : Amean 1 1.3100 ( 0.00%) 1.3923 ( -6.28%) 1.3427 ( -2.49%) : Amean 3 3.8860 ( 0.00%) 4.1230 * -6.10%* 3.8860 ( -0.00%) : Amean 5 6.8847 ( 0.00%) 8.0390 * -16.77%* 6.7727 ( 1.63%) : Amean 7 9.9310 ( 0.00%) 10.8367 * -9.12%* 9.9910 ( -0.60%) : Amean 12 16.6577 ( 0.00%) 18.2363 * -9.48%* 17.1083 ( -2.71%) : Amean 18 26.5133 ( 0.00%) 27.8833 * -5.17%* 25.7663 ( 2.82%) : Amean 24 34.3003 ( 0.00%) 34.6830 ( -1.12%) 32.0450 ( 6.58%) : Amean 30 40.0063 ( 0.00%) 40.5800 ( -1.43%) 41.5087 ( -3.76%) : Amean 32 40.1407 ( 0.00%) 41.2273 ( -2.71%) 39.9417 ( 0.50%) : : It's showing that the vanilla kernel takes a hit (as the bisection : indicated it would) and that disabling PSI by default is reasonably : close in terms of performance for this particular workload on this : particular machine so; Link: http://lkml.kernel.org/r/20181127165329.GA29728@cmpxchg.org Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Tested-by: Mel Gorman <mgorman@techsingularity.net> Reported-by: Mel Gorman <mgorman@techsingularity.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> (cherry picked from commit e0c274472d5d27f277af722e017525e0b33784cd) Bug: 127712811 Test: lmkd in PSI mode Change-Id: I6cb666fa351e8901df82e4d6931bfec0c5ce230d Signed-off-by: Suren Baghdasaryan <surenb@google.com>		2019-03-21 16:25:27 -07:00
..
ABI	ANDROID: cpufreq: times: add /proc/uid_concurrent_{active,policy}_time	2019-03-06 16:01:57 +00:00
accelerators	ocxl: Document new OCXL IOCTLs	2018-06-03 20:40:33 +10:00
accounting	UPSTREAM: psi: cgroup support	2019-03-21 16:25:27 -07:00
acpi	ACPI: property: graph: Update graph documentation to use generic references	2018-07-23 12:44:52 +02:00
admin-guide	UPSTREAM: psi: make disabling/enabling easier for vendor kernels	2019-03-21 16:25:27 -07:00
aoe
arm	ARM: Device-tree updates	2018-06-11 17:57:38 -07:00
arm64	Documentation/arm64/sve: Couple of improvements and typos	2018-08-29 11:33:19 +01:00
auxdisplay	Doc: misc-devices: move lcd-panel-cgram.txt to auxdisplay/	2018-04-12 16:08:02 +02:00
backlight
block	block: Track DISCARD statistics and output them in stat and diskstat	2018-07-18 08:44:22 -06:00
blockdev	UPSTREAM: zram: idle writeback fixes and cleanup	2019-01-22 10:22:17 -08:00
bpf	Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next	2018-08-07 11:02:05 -07:00
bus-devices
cdrom	Documentation/cdrom: fix German sharp s in LaTex	2018-03-08 19:35:29 -07:00
cgroup-v1	page cache: use xa_lock	2018-04-11 10:28:39 -07:00
cma
connector
console	Documentation: corrections to console/console.txt	2018-08-10 16:09:40 -06:00
core-api	idr: Change documentation license	2018-10-15 16:31:29 -04:00
cpu-freq	cpufreq: Drop cpufreq_table_validate_and_show()	2018-04-10 08:40:45 +02:00
cpuidle	cpuidle: Add definition of residency to sysfs documentation	2018-04-09 13:44:37 +02:00
crypto	crypto: remove redundant type flags from tfm allocation	2018-07-09 00:30:29 +08:00
dev-tools	doc: dev-tools: kselftest.rst: update contributing new tests	2018-06-29 09:01:50 -06:00
device-mapper	dm raid: bump target version, update comments and documentation	2018-09-06 17:07:58 -04:00
devicetree	dt-bindings: eeprom: at24: add "atmel,24c2048" compatible string	2019-02-20 10:25:35 +01:00
doc-guide	Documentation/sphinx: allow "functions" with no parameters	2018-06-30 07:52:42 -06:00
driver-api	docs: fpga: document fpga manager flags	2018-09-30 08:49:55 -07:00
driver-model	dmaengine: add a new helper dmaenginem_async_device_register	2018-07-30 10:50:22 +05:30
early-userspace	initramfs: move gen_initramfs_list.sh from scripts/ to usr/	2018-08-22 23:21:44 +09:00
EDID
extcon
fault-injection	Documentation: nvme: Documentation for nvme fault injection	2018-03-26 08:53:43 -06:00
fb	uvesafb: Fix URLs in the documentation	2018-09-26 18:11:23 +02:00
features	ARM: 8777/1: Hook up SYNC_CORE functionality for sys_membarrier()	2018-07-11 11:02:08 +01:00
filesystems	ANDROID: overlayfs: override_creds=off option bypass creator_cred	2019-03-05 21:49:08 +00:00
firmware_class
fmc
fpga	docs: fpga: add a document for FPGA Device Feature List (DFL) Framework Overview	2018-07-15 13:55:44 +02:00
gpio	Documentation: gpio: Move drivers-on-gpio.txt to driver-api	2018-03-23 04:22:29 +01:00
gpu	drm/msm/gpu: Add the buffer objects from the submit to the crash dump	2018-07-30 08:50:10 -04:00
hid	Documentation: fix input related doc refs	2017-10-12 11:14:06 -06:00
hwmon	hwmon: (ina2xx) fix sysfs shunt resistor read access	2018-08-26 17:45:25 -07:00
i2c	i2c: refactor function to release a DMA safe buffer	2018-08-30 23:13:15 +02:00
ia64	ia64: doc: tweak whitespace for 'console=' parameter	2018-03-05 14:41:38 -08:00
ide
iio
infiniband	Documentation/ABI: update infiniband sysfs interfaces	2018-02-23 08:18:33 -07:00
input	input: add MT_TOOL_DIAL	2018-07-17 15:33:47 +02:00
ioctl	Char/Misc driver patches for 4.19-rc1	2018-08-18 11:04:51 -07:00
isdn	Documentation/isdn: check and fix dead links ...	2018-03-26 12:31:13 -04:00
kbuild	kbuild: Fix LOADLIBES rename in Documentation/kbuild/makefiles.txt	2018-08-22 23:21:42 +09:00
kdump
kernel-hacking	doc:it_IT: translation for kernel-hacking	2018-07-26 16:21:09 -06:00
laptops	platform/x86: thinkpad_acpi: silence HKEY 0x6032, 0x60f0, 0x6030	2018-05-07 15:10:31 +03:00
leds	Documentation: leds: Update 00-INDEX file	2017-10-23 20:17:03 +02:00
lightnvm
livepatch	livepatch: Remove not longer valid limitations from the documentation	2018-05-24 15:37:57 +02:00
locking	locking: Implement an algorithm choice for Wound-Wait mutexes	2018-07-03 09:44:36 +02:00
m68k
maintainer	docs: Fix more broken references	2018-06-15 18:11:26 -03:00
md	raid5-ppl: PPL support for disks with write-back cache enabled	2018-01-15 14:29:42 -08:00
media	media: replace ADOBERGB by OPRGB	2018-11-13 11:08:54 -08:00
memory-devices
mic
mips	Documentation: mips: Update AU1xxx_IDE Kconfig dependencies	2018-02-01 12:45:35 -07:00
misc-devices	pci_endpoint_test: Add 2 ioctl commands	2018-07-19 11:46:57 +01:00
mmc
mtd	mtd: spi-nor: add an API to restore the status of SPI flash chip	2017-12-13 00:36:00 +01:00
namespaces
netlabel
networking	net-tcp: /proc/sys/net/ipv4/tcp_probe_interval is a u32 not int	2018-09-26 20:33:21 -07:00
nfc
nios2
nvdimm
nvmem
openrisc	Documentation: openrisc: Updates to README	2017-10-30 21:37:53 +09:00
parisc
PCI	Merge branch 'remotes/lorenzo/pci/dwc'	2018-08-15 14:59:11 -05:00
pcmcia	pcmcia: remove long deprecated pcmcia_request_exclusive_irq() function	2018-08-18 12:30:42 -07:00
perf	drivers/bus: Move Arm CCN PMU driver	2018-03-06 17:26:15 +01:00
phy
platform
power	ANDROID: PM / EM: Document the support for legacy (deprecated) EM	2019-03-08 00:50:07 +00:00
powerpc	powerpc: Document issues with TM on POWER9	2018-07-02 23:54:29 +10:00
pps
process	Code of Conduct: Change the contact email address	2018-10-22 07:33:36 +01:00
pti
ptp	ptp: Fix documentation to match code.	2018-03-26 12:13:21 -04:00
rapidio	Documentation: rapidio: move sysfs interface to ABI	2018-02-23 08:25:45 -07:00
RCU	rculist: Improve documentation for list_for_each_entry_from_rcu()	2018-07-12 15:39:25 -07:00
riscv	perf: riscv: Add Document for Future Porting Guide	2018-06-04 14:02:11 -07:00
s390	vfio-ccw: update documentation	2018-03-01 17:32:14 +01:00
scheduler	UPSTREAM: sched/doc: Document Energy Aware Scheduling	2019-03-08 00:49:55 +00:00
scsi	scsi: documentation: add scsi_mod.use_blk_mq to scsi-parameters	2018-08-27 12:26:10 -04:00
security	Kbuild: rename CC_STACKPROTECTOR[_STRONG] config variables	2018-06-14 12:21:18 +09:00
serial
sh
sound	ASoC: Updates for v4.19	2018-08-13 12:12:31 +02:00
sparc	sparc64: Add support for ADI (Application Data Integrity)	2018-03-18 07:38:48 -07:00
sphinx	Documentation/sphinx: allow "functions" with no parameters	2018-06-30 07:52:42 -06:00
sphinx-static
spi
sysctl	ANDROID: security,perf: Allow further restriction of perf_event_open	2018-12-05 09:48:13 -08:00
target
thermal	thermal: Add cooling device's statistics in sysfs	2018-04-02 21:49:01 +08:00
timers	timekeeping.txt: Correct maxCount of n-bit binary counter	2018-07-23 09:33:06 -06:00
trace	This was a moderately busy cycle for docs, with the usual collection of	2018-08-14 14:29:31 -07:00
translations	This was a moderately busy cycle for docs, with the usual collection of	2018-08-14 14:29:31 -07:00
usb	USB-serial updates for v4.19-rc1	2018-07-20 21:47:15 +02:00
userspace-api	x86/speculation: Add prctl() control for indirect branch speculation	2018-12-05 19:32:04 +01:00
virtual	KVM: x86: Control guest reads of MSR_PLATFORM_INFO	2018-09-20 00:51:46 +02:00
vm	docs/vm: move ksm and transhuge from "user" to "internals" section.	2018-05-29 06:45:55 -06:00
w1	w1: fix w1_ds2438 documentation	2018-07-07 17:27:13 +02:00
watchdog	watchdog: remove bfin_wdt driver	2018-03-26 15:57:04 +02:00
wimax
x86	x86/mm: Move LDT remap out of KASLR region on 5-level paging	2018-11-27 16:13:08 +01:00
xtensa	xtensa: add support for KASAN	2017-12-16 22:37:12 -08:00
.gitignore
00-INDEX	docs: admin-guide: add cgroup-v2 documentation	2018-05-10 15:42:41 -06:00
atomic_bitops.txt	locking/atomic/bitops: Document and clarify ordering semantics for failed test_and_{}_bit()	2018-02-13 14:55:53 +01:00
atomic_t.txt
bt8xxgpio.txt
btmrvl.txt
bus-virt-phys-mapping.txt
Changes
clearing-warn-once.txt	kernel debug: support resetting WARN*_ONCE	2017-11-17 16:10:00 -08:00
CodingStyle
conf.py	ext4: import inode data fork chapter from wiki page	2018-07-29 15:45:00 -04:00
cpu-load.txt
cputopology.txt
crc32.txt
dcdbas.txt
debugging-modules.txt
debugging-via-ohci1394.txt
dell_rbu.txt	Documentation: remove stale firmware API reference	2018-05-14 16:44:41 +02:00
digsig.txt
DMA-API-HOWTO.txt
DMA-API.txt
DMA-attributes.txt
DMA-ISA-LPC.txt
docutils.conf
dontdiff
efi-stub.txt
eisa.txt
flexible-arrays.txt
futex-requeue-pi.txt
gcc-plugins.txt
highuid.txt
hw_random.txt
hwspinlock.txt
index.rst	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next	2018-08-15 15:04:25 -07:00
Intel-IOMMU.txt
intel_txt.txt
io-mapping.txt
io_ordering.txt
iostats.txt	block: Track DISCARD statistics and output them in stat and diskstat	2018-07-18 08:44:22 -06:00
IPMI.txt
IRQ-affinity.txt
IRQ-domain.txt	irqdomain: Kill CONFIG_IRQ_DOMAIN_DEBUG	2018-01-24 12:32:58 +01:00
IRQ.txt
irqflags-tracing.txt
isa.txt
isapnp.txt
kernel-per-CPU-kthreads.txt
kobject.txt
kprobes.txt	kprobes/Documentation: Fix various typos	2018-06-22 11:10:55 +02:00
kref.txt
ldm.txt
lockup-watchdogs.txt
logo.gif
logo.txt
lsm.txt
lzo.txt
mailbox.txt
Makefile	Documentation: add script and build target to check for broken file references	2017-10-12 11:07:42 -06:00
memory-barriers.txt	sched/Documentation: Update wake_up() & co. memory-barrier guarantees	2018-07-17 09:30:34 +02:00
memory-hotplug.txt
men-chameleon-bus.txt
nommu-mmap.txt	Documentation: nommu-map: Fix duplicate word typo	2018-06-26 09:01:27 -06:00
ntb.txt
numastat.txt
padata.txt
parport-lowlevel.txt
percpu-rw-semaphore.txt
phy.txt
pi-futex.txt	Documentation: fix locking rt-mutex doc refs	2017-10-19 12:56:44 -06:00
pnp.txt
preempt-locking.txt
pwm.txt
rbtree.txt
remoteproc.txt
rfkill.txt	rfkill: Fix several typos in documentation	2018-06-15 13:36:08 +02:00
robust-futex-ABI.txt
robust-futexes.txt
rpmsg.txt
rtc.txt	Documentation: rtc: move iotcl interface documentation to ABI	2018-01-12 00:20:41 +01:00
SAK.txt
sgi-ioc4.txt
siphash.txt
SM501.txt
smsc_ece1099.txt
speculation.txt	Documentation: Document array_index_nospec	2018-01-30 21:54:28 +01:00
static-keys.txt
SubmittingPatches
svga.txt	documentation/svga.txt: update outdated file	2017-11-20 10:45:50 -07:00
switchtec.txt	NTB: switchtec_ntb: Update switchtec documentation with notes for NTB	2017-11-18 20:37:13 -05:00
sync_file.txt
tee.txt
this_cpu_ops.txt
unaligned-memory-access.txt
vfio-mediated-device.txt	vfio/mdev: Check globally for duplicate devices	2018-06-08 10:24:27 -06:00
vfio.txt	vfio: fix documentation	2018-05-08 09:16:41 -06:00
video-output.txt
xillybus.txt
xz.txt
zorro.txt