Chris Metcalf fe4ba3c343 watchdog: add watchdog_cpumask sysctl to assist nohz ... Change the default behavior of watchdog so it only runs on the housekeeping cores when nohz_full is enabled at build and boot time. Allow modifying the set of cores the watchdog is currently running on with a new kernel.watchdog_cpumask sysctl. In the current system, the watchdog subsystem runs a periodic timer that schedules the watchdog kthread to run. However, nohz_full cores are designed to allow userspace application code running on those cores to have 100% access to the CPU. So the watchdog system prevents the nohz_full application code from being able to run the way it wants to, thus the motivation to suppress the watchdog on nohz_full cores, which this patchset provides by default. However, if we disable the watchdog globally, then the housekeeping cores can't benefit from the watchdog functionality. So we allow disabling it only on some cores. See Documentation/lockup-watchdogs.txt for more information. [jhubbard@nvidia.com: fix a watchdog crash in some configurations] Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com> Acked-by: Don Zickus <dzickus@redhat.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Ulrich Obergfell <uobergfe@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: John Hubbard <jhubbard@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2015-06-24 17:49:40 -07:00
..
ABI	powerpc updates for 4.2	2015-06-24 08:46:32 -07:00
DocBook	Merge branch 'mvebu/drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc	2015-06-19 22:07:07 +08:00
EDID	…
PCI	The documentation tree update for 4.1. Numerous fixes, the overdue removal	2015-04-18 11:10:49 -04:00
RCU	Merge branches 'array.2015.05.27a', 'doc.2015.05.27a', 'fixes.2015.05.27a', 'hotplug.2015.05.27a', 'init.2015.05.27a', 'tiny.2015.05.27a' and 'torture.2015.05.27a' into HEAD	2015-05-27 13:00:49 -07:00
accounting	…
acpi	ACPI: Constify ACPI device IDs in documentation	2015-06-19 01:14:15 +02:00
aoe	…
arm	ARM: SoC multiplatform code changes for v4.1	2015-04-22 09:20:15 -07:00
arm64	arm64: use fixmap region for permanent FDT mapping	2015-06-02 16:31:33 +01:00
auxdisplay	…
backlight	…
blackfin	Documentation: blackfin: Makefile: Typo building issue	2015-04-11 15:19:31 +02:00
block	Documentation: Remove mentioning of block barriers	2015-03-20 07:41:56 -06:00
blockdev	Merge branch 'for-4.1/drivers' of git://git.kernel.dk/linux-block	2015-04-16 22:05:27 -04:00
bus-devices	…
cdrom	…
cgroups	The documentation tree update for 4.1. Numerous fixes, the overdue removal	2015-04-18 11:10:49 -04:00
cma	cma: debug: document new debugfs interface	2015-04-14 16:49:00 -07:00
connector	…
console	…
cpu-freq	Documentation: cpufreq: delete duplicate description of sysfs interface 'scaling_driver'	2015-05-05 23:23:25 +02:00
cpuidle	…
cris	…
crypto	crypto: doc - AEAD / RNG AF_ALG interface	2015-03-09 21:06:18 +11:00
development-process	…
device-mapper	dm crypt: update URLs to new cryptsetup project page	2015-04-15 12:10:24 -04:00
devicetree	powerpc updates for 4.2	2015-06-24 08:46:32 -07:00
dmaengine	Merge branch 'for-linus' of git://git.infradead.org/users/vkoul/slave-dma	2015-02-18 08:49:20 -08:00
driver-model	Char/Misc driver patches for 4.1-rc1	2015-04-21 09:42:58 -07:00
dvb	…
early-userspace	…
extcon	…
fault-injection	…
fb	…
filesystems	Documentation: remove outdated information from automount-support.txt	2015-05-15 01:10:38 -04:00
firmware_class	…
fmc	…
frv	…
gpio	fix documentation after renaming gpiod_set_array to gpiod_set_array_value	2015-06-04 10:46:43 +02:00
hid	HID: sensor: Update document for custom sensor	2015-04-10 22:22:56 +02:00
hwmon	hwmon: add driver for Microchip TC74	2015-06-21 22:54:53 -07:00
i2c	i2c: slave: fix the example how to instantiate from userspace	2015-06-17 14:16:27 +02:00
ia64	virtual: Documentation: simplify and generalize paravirt_ops.txt	2015-02-13 17:15:44 +10:30
ide	…
infiniband	…
input	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input	2015-04-21 12:54:08 -07:00
ioctl	platform/chrome: Add Chrome OS EC userspace device interface	2015-02-26 15:45:06 -08:00
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	thinkpad_acpi: Add adaptive_kbd_mode sysfs attr	2015-03-03 09:00:08 -08:00
leds	Documentation: leds: Add description of LED Flash class extension	2015-03-09 17:18:00 -07:00
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	…
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	Doc: networking: Fix URL for wiki.wireshark.org in udplite.txt	2015-06-12 14:21:29 -07:00
nfc	…
nios2	Documentation: Add documentation for Nios2 architecture	2014-12-08 12:56:06 +08:00
parisc	…
pcmcia	…
phy	…
platform	…
power	PM / runtime: add note about re-calling in during device probe()	2015-05-13 00:02:38 +02:00
powerpc	powerpc/tm: Abort syscalls in active transactions	2015-06-19 17:10:28 +10:00
pps	…
prctl	…
pti	…
ptp	…
rapidio	…
s390	s390/docs: Remove section about script debugging from Debugging390.txt	2015-01-15 11:11:14 +01:00
scheduler	sched/dl/Documentation: Split Section 3	2015-05-19 08:39:21 +02:00
scsi	st: implement tape statistics	2015-06-02 08:03:25 -07:00
security	Smack: Updates for Smack documentation	2015-03-31 10:35:31 -07:00
serial	pty: Fix input race when closing	2015-05-10 19:26:37 +02:00
sh	…
sound	ASoC: Updates for v4.1	2015-04-13 14:14:29 +02:00
spi	Documentation/spi/spidev_test.c: fix warning	2015-04-17 09:04:12 -04:00
sysctl	watchdog: add watchdog_cpumask sysctl to assist nohz	2015-06-24 17:49:40 -07:00
target	SCSI misc on 20150622	2015-06-23 15:55:44 -07:00
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	coresight: Correcting documentation typographical error	2015-04-03 16:17:03 +02:00
usb	usb: patches for v4.1 merge window	2015-03-24 22:57:49 +01:00
vDSO	…
video4linux	[media] media/Documentation: New flag EXECUTE_ON_WRITE	2015-04-08 06:35:16 -03:00
virtual	KVM: x86: mark legacy PCI device assignment as deprecated	2015-06-05 17:26:39 +02:00
vm	The documentation tree update for 4.1. Numerous fixes, the overdue removal	2015-04-18 11:10:49 -04:00
w1	…
watchdog	…
wimax	…
x86	Merge branch 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2015-06-22 17:59:09 -07:00
xtensa	…
zh_CN	gpio: remove gpiod_sysfs_set_active_low	2015-05-12 10:46:53 +02:00
00-INDEX	Update of Documentation/dmaengine/00-INDEX	2014-12-29 15:28:24 -07:00
BUG-HUNTING	…
Changes	Documentation: GNU is frequently spelled Gnu	2014-12-29 15:33:17 -07:00
CodeOfConflict	Code of Conflict	2015-02-27 11:44:24 -08:00
CodingStyle	The documentation tree update for 4.1. Numerous fixes, the overdue removal	2015-04-18 11:10:49 -04:00
DMA-API-HOWTO.txt	PCI: Add pci_bus_addr_t	2015-05-29 17:21:45 -05:00
DMA-API.txt	PCI: Add pci_bus_addr_t	2015-05-29 17:21:45 -05:00
DMA-ISA-LPC.txt	…
DMA-attributes.txt	…
HOWTO	…
IPMI.txt	ipmi:ssif: Ignore spaces when comparing I2C adapter names	2015-05-05 14:24:45 -05:00
IRQ-affinity.txt	…
IRQ-domain.txt	IRQCHIP: Update docs regarding irq_domain_add_tree()	2015-04-01 17:21:35 +02:00
IRQ.txt	…
Intel-IOMMU.txt	…
Makefile	Documentation: Remove ZBOOT MMC/SDHI utility and docs	2015-02-24 06:45:25 +09:00
ManagementStyle	…
SAK.txt	…
SM501.txt	…
SecurityBugs	…
SubmitChecklist	…
SubmittingDrivers	…
SubmittingPatches	checkpatch, SubmittingPatches: suggest line wrapping commit messages at 75 columns	2015-04-17 09:03:57 -04:00
VGA-softcursor.txt	…
applying-patches.txt	…
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	…
braille-console.txt	…
bt8xxgpio.txt	…
btmrvl.txt	…
bus-virt-phys-mapping.txt	…
cachetlb.txt	rmap: drop support of non-linear mappings	2015-02-10 14:30:31 -08:00
circular-buffers.txt	…
clk.txt	clk: Add rate constraints to clocks	2015-02-02 14:23:42 -08:00
coccinelle.txt	…
cpu-hotplug.txt	cpumask: fix cpu-hotplug documentation	2015-03-05 13:37:01 +10:30
cpu-load.txt	…
cputopology.txt	Documentation: Update cputopology.txt	2015-05-27 15:22:15 +02:00
crc32.txt	…
dcdbas.txt	…
debugging-modules.txt	…
debugging-via-ohci1394.txt	…
dell_rbu.txt	…
devices.txt	…
digsig.txt	…
dma-buf-sharing.txt	dma-buf: cleanup dma_buf_export() to make it easily extensible	2015-04-21 14:47:16 +05:30
dontdiff	…
dynamic-debug-howto.txt	…
edac.txt	…
efi-stub.txt	…
eisa.txt	…
email-clients.txt	Documentation/email-clients.txt: Fix one grammar mistake, add extra info about TB	2015-03-20 07:41:55 -06:00
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	…
hsi.txt	…
hw_random.txt	…
hwspinlock.txt	…
init.txt	…
initrd.txt	…
intel_txt.txt	…
io-mapping.txt	…
io_ordering.txt	…
iostats.txt	…
irqflags-tracing.txt	…
isapnp.txt	…
java.txt	…
kasan.txt	kasan: show gcc version requirements in Kconfig and Documentation	2015-05-05 17:10:10 -07:00
kernel-doc-nano-HOWTO.txt	…
kernel-docs.txt	…
kernel-parameters.txt	Power management and ACPI material for v4.2-rc1	2015-06-23 14:18:07 -07:00
kernel-per-CPU-kthreads.txt	documentation: Update per-CPU kthreads documentation	2015-02-26 11:57:30 -08:00
kmemcheck.txt	Documentation: update the CONFIG_DEBUG_PAGEALLOC description	2015-03-20 07:41:55 -06:00
kmemleak.txt	…
kobject.txt	kobject: grammar fix	2014-12-08 09:07:11 -05:00
kprobes.txt	kprobes: Update Documentation/kprobes.txt	2015-03-20 07:41:55 -06:00
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	watchdog: add watchdog_cpumask sysctl to assist nohz	2015-06-24 17:49:40 -07:00
logo.gif	…
logo.txt	…
lzo.txt	…
magic-number.txt	…
mailbox.txt	Documentation: Fix a typo in mailbox.txt	2014-11-03 11:54:50 -05:00
md-cluster.txt	md-cluster: Design Documentation	2015-02-23 07:16:46 -06:00
md.txt	…
media-framework.txt	…
memory-barriers.txt	Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2015-06-22 14:54:22 -07:00
memory-hotplug.txt	mem-hotplug: fix typo in Documentation/memory-hotplug.txt	2015-03-20 07:41:55 -06:00
module-signing.txt	modsign: change default key details	2015-04-30 09:35:41 -07:00
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	x86/fpu: Rename math_state_restore() to fpu__restore()	2015-05-19 15:47:18 +02:00
printk-formats.txt	The documentation tree update for 4.1. Numerous fixes, the overdue removal	2015-04-18 11:10:49 -04:00
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
serial-console.txt	…
sgi-ioc4.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	…
svga.txt	…
sysfs-rules.txt	…
sysrq.txt	…
this_cpu_ops.txt	…
unaligned-memory-access.txt	…
unicode.txt	…
unshare.txt	…
vfio.txt	vfio: powerpc/spapr: Support Dynamic DMA windows	2015-06-11 15:16:55 +10:00
vgaarbiter.txt	…
video-output.txt	…
vme_api.txt	…
volatile-considered-harmful.txt	…
workqueue.txt	…
xillybus.txt	…
xz.txt	…
zorro.txt	…