Eric B Munson 5bbe3547aa mm: allow compaction of unevictable pages ... Currently, pages which are marked as unevictable are protected from compaction, but not from other types of migration. The POSIX real time extension explicitly states that mlock() will prevent a major page fault, but the spirit of this is that mlock() should give a process the ability to control sources of latency, including minor page faults. However, the mlock manpage only explicitly says that a locked page will not be written to swap and this can cause some confusion. The compaction code today does not give a developer who wants to avoid swap but wants to have large contiguous areas available any method to achieve this state. This patch introduces a sysctl for controlling compaction behavior with respect to the unevictable lru. Users who demand no page faults after a page is present can set compact_unevictable_allowed to 0 and users who need the large contiguous areas can enable compaction on locked memory by leaving the default value of 1. To illustrate this problem I wrote a quick test program that mmaps a large number of 1MB files filled with random data. These maps are created locked and read only. Then every other mmap is unmapped and I attempt to allocate huge pages to the static huge page pool. When the compact_unevictable_allowed sysctl is 0, I cannot allocate hugepages after fragmenting memory. When the value is set to 1, allocations succeed. Signed-off-by: Eric B Munson <emunson@akamai.com> Acked-by: Michal Hocko <mhocko@suse.cz> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Christoph Lameter <cl@linux.com> Acked-by: David Rientjes <rientjes@google.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Christoph Lameter <cl@linux.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mel Gorman <mgorman@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2015-04-15 16:35:17 -07:00
..
ABI	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next	2015-04-15 09:00:47 -07:00
accounting	Documentation: use subdir-y to avoid unnecessary built-in.o files	2014-09-26 11:02:55 +02:00
acpi	Power management and ACPI updates for v4.1-rc1	2015-04-14 20:21:54 -07:00
aoe
arm	ARM: SoC platform changes	2015-02-17 09:27:54 -08:00
arm64	arm64: Emulate SETEND for AArch32 tasks	2015-01-23 17:11:44 +00:00
auxdisplay	Documentation: use subdir-y to avoid unnecessary built-in.o files	2014-09-26 11:02:55 +02:00
backlight
blackfin	Documentation: fix blackfin gptimers-example build errors	2015-01-28 12:07:58 -07:00
block	Merge branch 'for-3.19/core' of git://git.kernel.dk/linux-block	2014-12-13 14:14:23 -08:00
blockdev	zram: report maximum used memory	2014-10-09 22:26:02 -04:00
bus-devices
cdrom
cgroups	Merge branch 'for-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup	2015-04-13 16:47:11 -07:00
cma	cma: debug: document new debugfs interface	2015-04-14 16:49:00 -07:00
connector
console
cpu-freq	intel_pstate: Add num_pstates to sysfs	2015-01-30 01:52:17 +01:00
cpuidle
cris
crypto	crypto: doc - userspace interface spec	2014-11-13 22:31:38 +08:00
development-process	Documentation: remove outdated references to the linux-next wiki	2014-10-28 09:06:11 -04:00
device-mapper	dm crypt: add 'submit_from_crypt_cpus' option	2015-02-16 11:11:15 -05:00
devicetree	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next	2015-04-15 09:00:47 -07:00
dmaengine	Merge branch 'for-linus' of git://git.infradead.org/users/vkoul/slave-dma	2015-02-18 08:49:20 -08:00
DocBook	KGDB/KDB New:	2015-02-20 15:13:29 -08:00
driver-model	Staging drivers patches for 3.20-rc1	2015-02-15 11:30:39 -08:00
dvb	[media] get_dvb_firmware: Update firmware of ITEtech IT9135	2014-09-21 17:03:04 -03:00
early-userspace
EDID
extcon
fault-injection
fb
filesystems	ocfs2: update web page + git tree in documentation	2015-02-28 09:57:50 -08:00
firmware_class
fmc
frv
gpio	gpio: board.txt: Fix the gpio name example	2015-01-28 11:14:00 -07:00
hid	HID: sensor: Update document for custom sensor	2015-04-10 22:22:56 +02:00
hwmon	hwmon: (it87) Add support for IT8620E	2015-04-05 06:01:00 -07:00
i2c	i2c: slave: add documentation for i2c-slave-eeprom	2015-03-27 16:53:39 +01:00
i2o
ia64	virtual: Documentation: simplify and generalize paravirt_ops.txt	2015-02-13 17:15:44 +10:30
ide
infiniband
input	Input: alps - document stick behavior for protocol V2	2015-04-05 11:48:35 -07:00
ioctl	cxl: Add documentation for userspace APIs	2014-10-08 20:16:19 +11:00
isdn
ja_JP
kbuild	Merge branch 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild	2015-02-19 10:31:37 -08:00
kdump	kernel: add panic_on_warn	2014-12-10 17:41:10 -08:00
ko_KR
laptops	Documentation: update .gitignore files	2014-09-26 11:02:59 +02:00
leds
locking	Documentation changes for 3.20	2015-02-11 13:03:11 -08:00
m68k
memory-devices
metag
mic	Documentation: Build mic/mpssd only for x86_64	2014-12-05 11:18:36 -05:00
mips	Documentation: au1xxx-ide.c has moved	2014-08-26 09:35:53 +02:00
misc-devices	Documentation/misc-devices/mei: Fix indentation of embedded code.	2015-01-29 12:56:20 -07:00
mmc
mn10300
mtd
namespaces
netlabel
networking	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net	2015-04-14 15:44:14 -04:00
nfc
nios2	Documentation: Add documentation for Nios2 architecture	2014-12-08 12:56:06 +08:00
parisc
PCI	PCI: Clarify policy for vendor IDs in pci.txt	2015-04-09 13:34:02 -05:00
pcmcia	Documentation: use subdir-y to avoid unnecessary built-in.o files	2014-09-26 11:02:55 +02:00
phy
platform
power	Power management and ACPI updates for v4.1-rc1	2015-04-14 20:21:54 -07:00
powerpc	cxl: Add documentation for userspace APIs	2014-10-08 20:16:19 +11:00
pps
prctl	Documentation: Restrict TSC test code to x86	2014-10-28 08:46:27 -04:00
pti
ptp	ptp: restore the makefile for building the test program.	2014-10-24 16:07:10 -04:00
rapidio
RCU	Merge branches 'doc.2015.01.07a', 'fixes.2015.01.15a', 'preempt.2015.01.06a', 'srcu.2015.01.06a', 'stall.2015.01.16a' and 'torture.2015.01.11a' into HEAD	2015-01-15 23:34:34 -08:00
s390	s390/docs: Remove section about script debugging from Debugging390.txt	2015-01-15 11:11:14 +01:00
scheduler	doc: brief user documentation for completion	2015-01-30 11:19:25 -07:00
scsi	genirq: Remove the deprecated 'IRQF_DISABLED' request_irq() flag entirely	2015-03-05 20:53:06 +01:00
security	KEYS: Make /proc/keys unconditional if CONFIG_KEYS=y	2015-01-22 22:34:32 +00:00
serial	serial: Fix locking for uart driver set_termios() method	2014-11-05 18:53:54 -08:00
sh
sound	ALSA: hda - Add "eapd" model string for AD1986A codec	2014-12-10 14:00:13 +01:00
spi	Merge remote-tracking branches 'spi/topic/spidev' and 'spi/topic/spidev-test' into spi-next	2015-04-11 23:09:31 +01:00
sysctl	mm: allow compaction of unevictable pages	2015-04-15 16:35:17 -07:00
target	Documentation/target: Update fabric_ops to latest code	2015-01-06 13:46:49 -08:00
thermal	Documentation: thermal: document of_cpufreq_cooling_register()	2015-01-06 14:39:17 -04:00
timers	documentation: Update NO_HZ_FULL interaction with POSIX timers	2015-02-26 11:57:29 -08:00
tpm
trace	Char / Misc patches for 3.20-rc1	2015-02-15 10:48:44 -08:00
usb	usb: patches for v4.1 merge window	2015-03-24 22:57:49 +01:00
vDSO	vdso: don't require 64-bit math in standalone test	2014-10-25 10:53:44 -04:00
video4linux	MODULE_DEVICE_TABLE: fix some callsites	2015-02-13 21:21:40 -08:00
virtual	Features and fixes for 4.1 (kvm/next)	2015-04-07 18:10:03 +02:00
vm	cleancache: forbid overriding cleancache_ops	2015-04-14 16:49:03 -07:00
w1
watchdog	Documentation: use subdir-y to avoid unnecessary built-in.o files	2014-09-26 11:02:55 +02:00
wimax
x86	x86/mm/KASLR: Propagate KASLR status to kernel proper	2015-04-03 15:26:15 +02:00
xtensa
zh_CN
00-INDEX	Update of Documentation/dmaengine/00-INDEX	2014-12-29 15:28:24 -07:00
applying-patches.txt	Documentation: change "&" to "and" in Documentation/applying-patches.txt	2014-09-26 11:10:11 +02:00
assoc_array.txt
atomic_ops.txt	documentation: Clarify memory-barrier semantics of atomic operations	2015-02-26 11:57:31 -08:00
bad_memory.txt
basic_profiling.txt
bcache.txt
binfmt_misc.txt	binfmt_misc: touch up documentation a bit	2014-10-14 02:18:16 +02:00
braille-console.txt
bt8xxgpio.txt
btmrvl.txt
BUG-HUNTING
bus-virt-phys-mapping.txt
cachetlb.txt	rmap: drop support of non-linear mappings	2015-02-10 14:30:31 -08:00
Changes	Documentation: GNU is frequently spelled Gnu	2014-12-29 15:33:17 -07:00
circular-buffers.txt
clk.txt	clk: Add rate constraints to clocks	2015-02-02 14:23:42 -08:00
coccinelle.txt
CodeOfConflict	Code of Conflict	2015-02-27 11:44:24 -08:00
CodingStyle	CodingStyle: enable emacs display of trailing whitespace	2015-01-28 12:05:46 -07:00
cpu-hotplug.txt
cpu-load.txt
cputopology.txt
crc32.txt
dcdbas.txt
debugging-modules.txt
debugging-via-ohci1394.txt
dell_rbu.txt
devices.txt
digsig.txt
DMA-API-HOWTO.txt	Documentation: correct parameter error for dma_mapping_error	2014-09-26 11:22:29 +02:00
DMA-API.txt
DMA-attributes.txt
dma-buf-sharing.txt	Documentation/dma-buf-sharing.txt: update API descriptions	2014-08-28 11:57:24 +05:30
DMA-ISA-LPC.txt
dontdiff
dynamic-debug-howto.txt
edac.txt
efi-stub.txt
eisa.txt
email-clients.txt	Documentation/email-clients.txt: add info about Claws Mail	2014-12-02 11:55:29 -05:00
flexible-arrays.txt
futex-requeue-pi.txt	doc: Fix misnamed FUTEX_CMP_REQUEUE_PI op constants	2015-01-19 12:05:32 +01:00
gcov.txt
gdb-kernel-debugging.txt	scripts/gdb: add basic documentation	2015-02-17 14:34:54 -08:00
highuid.txt
HOWTO	Documentation: remove outdated references to the linux-next wiki	2014-10-28 09:06:11 -04:00
hsi.txt
hw_random.txt
hwspinlock.txt
init.txt
initrd.txt
Intel-IOMMU.txt
intel_txt.txt
io-mapping.txt
io_ordering.txt
iostats.txt
IPMI.txt	ipmi: Add SMBus interface driver (SSIF)	2014-12-11 15:04:11 -06:00
IRQ-affinity.txt
IRQ-domain.txt	irqdomain: Introduce new interfaces to support hierarchy irqdomains	2014-11-23 13:01:45 +01:00
IRQ.txt
irqflags-tracing.txt
isapnp.txt
java.txt
kasan.txt	kasan: enable instrumentation of global variables	2015-02-13 21:21:42 -08:00
kernel-doc-nano-HOWTO.txt
kernel-docs.txt
kernel-parameters.txt	Power management and ACPI updates for v4.1-rc1	2015-04-14 20:21:54 -07:00
kernel-per-CPU-kthreads.txt	documentation: Update per-CPU kthreads documentation	2015-02-26 11:57:30 -08:00
kmemcheck.txt
kmemleak.txt	Documentation: Add CONFIG_DEBUG_KMEMLEAK_DEFAULT_OFF case	2014-10-24 13:59:03 -04:00
kobject.txt	kobject: grammar fix	2014-12-08 09:07:11 -05:00
kprobes.txt	Documentation: add description for FTRACE probe status	2015-02-04 16:05:44 -05:00
kref.txt
kselftest.txt	kselftest: Move the docs to the Documentation dir	2014-11-24 10:49:54 -07:00
ldm.txt
local_ops.txt	percpu: update local_ops.txt to reflect this_cpu operations	2014-12-13 12:42:53 -08:00
lockup-watchdogs.txt	lockup-watchdogs: Fix a typo	2014-08-26 09:35:52 +02:00
logo.gif
logo.txt
lzo.txt	Documentation: lzo: document part of the encoding	2014-09-28 11:08:00 +02:00
magic-number.txt
mailbox.txt	Documentation: Fix a typo in mailbox.txt	2014-11-03 11:54:50 -05:00
Makefile	Documentation: add makefiles for more targets	2014-09-26 11:02:56 +02:00
ManagementStyle
md.txt
media-framework.txt
memory-barriers.txt	documentation: Clarify control-dependency pairing	2015-02-26 11:57:32 -08:00
memory-hotplug.txt	memory-hotplug: add sysfs valid_zones attribute	2014-10-09 22:25:52 -04:00
module-signing.txt
mono.txt
nommu-mmap.txt	fs: introduce f_op->mmap_capabilities for nommu mmap support	2015-01-20 14:02:58 -07:00
numastat.txt
oops-tracing.txt	livepatch: kernel: add TAINT_LIVEPATCH	2014-12-22 15:40:48 +01:00
padata.txt
parport-lowlevel.txt
parport.txt
percpu-rw-semaphore.txt
phy.txt	phy: improved lookup method	2014-11-21 19:48:50 +05:30
pi-futex.txt
pinctrl.txt	pinctrl: fix example .get_group_pins implementation signature	2015-03-18 02:02:20 +01:00
pnp.txt
preempt-locking.txt
printk-formats.txt	lib/vsprintf: add %*pE[achnops] format specifier	2014-10-14 02:18:26 +02:00
pwm.txt
ramoops.txt	pstore-ram: Allow optional mapping with pgprot_noncached	2014-12-11 13:38:31 -08:00
rbtree.txt
remoteproc.txt
rfkill.txt	rfkill: document rfkill module parameters	2015-01-09 23:22:12 +01:00
robust-futex-ABI.txt
robust-futexes.txt
rpmsg.txt
rtc.txt	Documentation, split up rtc.txt into documentation and test file	2015-03-24 22:01:58 -06:00
SAK.txt
SecurityBugs
serial-console.txt
sgi-ioc4.txt
SM501.txt
smsc_ece1099.txt
sparse.txt
stable_api_nonsense.txt
stable_kernel_rules.txt	stable_kernel_rules: Add clause about specification of kernel versions to patch.	2015-03-26 23:52:24 +01:00
static-keys.txt
SubmitChecklist
SubmittingDrivers
SubmittingPatches	Merge branch 'doc/sp-update' into docs-next	2015-01-29 13:11:58 -07:00
svga.txt
sysfs-rules.txt	Documentation/sysfs-rules.txt: Add device attribute error code documentation	2014-09-19 14:44:51 -07:00
sysrq.txt
this_cpu_ops.txt	Docs: this_cpu_ops: remove redundant add forms	2014-09-26 11:03:00 +02:00
unaligned-memory-access.txt
unicode.txt
unshare.txt
vfio.txt
VGA-softcursor.txt
vgaarbiter.txt
video-output.txt
vme_api.txt
volatile-considered-harmful.txt
workqueue.txt
xillybus.txt	xillybus: Move out of staging	2014-09-23 23:44:16 -07:00
xz.txt
zorro.txt