Dmitry Vyukov a2e5144538 kernel/hung_task.c: allow to set checking interval separately from timeout ... Currently task hung checking interval is equal to timeout, as the result hung is detected anywhere between timeout and 2*timeout. This is fine for most interactive environments, but this hurts automated testing setups (syzbot). In an automated setup we need to strictly order CPU lockup < RCU stall < workqueue lockup < task hung < silent loss, so that RCU stall is not detected as task hung and task hung is not detected as silent machine loss. The large variance in task hung detection timeout requires setting silent machine loss timeout to a very large value (e.g. if task hung is 3 mins, then silent loss need to be set to ~7 mins). The additional 3 minutes significantly reduce testing efficiency because usually we crash kernel within a minute, and this can add hours to bug localization process as it needs to do dozens of tests. Allow setting checking interval separately from timeout. This allows to set timeout to, say, 3 minutes, but checking interval to 10 secs. The interval is controlled via a new hung_task_check_interval_secs sysctl, similar to the existing hung_task_timeout_secs sysctl. The default value of 0 results in the current behavior: checking interval is equal to timeout. [akpm@linux-foundation.org: update hung_task_timeout_max's comment] Link: http://lkml.kernel.org/r/20180611111004.203513-1-dvyukov@google.com Signed-off-by: Dmitry Vyukov <dvyukov@google.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2018-08-22 10:52:47 -07:00
..
ABI	Char/Misc driver patches for 4.19-rc1	2018-08-18 11:04:51 -07:00
accelerators	ocxl: Document new OCXL IOCTLs	2018-06-03 20:40:33 +10:00
accounting
acpi	ACPI: property: graph: Update graph documentation to use generic references	2018-07-23 12:44:52 +02:00
admin-guide	mm, oom: introduce memory.oom.group	2018-08-22 10:52:45 -07:00
aoe
arm	ARM: Device-tree updates	2018-06-11 17:57:38 -07:00
arm64	ARM:	2018-04-09 11:42:31 -07:00
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	zram: introduce zram memory tracking	2018-06-07 17:34:34 -07:00
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	This was a moderately busy cycle for docs, with the usual collection of	2018-08-14 14:29:31 -07:00
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 thin: include metadata_low_watermark threshold in pool status	2018-07-30 11:49:08 -04:00
devicetree	RTC for 4.19	2018-08-20 16:30:27 -07:00
doc-guide	Documentation/sphinx: allow "functions" with no parameters	2018-06-30 07:52:42 -06:00
driver-api	Driver core patches for 4.19-rc1	2018-08-18 11:44:53 -07:00
driver-model	dmaengine: add a new helper dmaenginem_async_device_register	2018-07-30 10:50:22 +05:30
early-userspace
EDID
extcon
fault-injection	Documentation: nvme: Documentation for nvme fault injection	2018-03-26 08:53:43 -06:00
fb	console/fbcon: Add support for deferred console takeover	2018-06-28 15:20:30 +02:00
features	ARM: 8777/1: Hook up SYNC_CORE functionality for sys_membarrier()	2018-07-11 11:02:08 +01:00
filesystems	/proc/meminfo: add percpu populated pages count	2018-08-22 10:52:45 -07:00
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
hwmon	powerpc updates for 4.19	2018-08-17 11:32:50 -07:00
i2c	Merge branch 'i2c/for-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux	2018-06-14 16:21:46 +09:00
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	Kconfig updates for v4.19	2018-08-15 12:50:10 -07:00
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
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: doc: media/v4l-drivers: Update Qualcomm CAMSS driver document for 8x96	2018-08-02 08:48:00 -04:00
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
namespaces
netlabel
networking	Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf	2018-08-18 09:59:19 -07:00
nfc
nios2
nvdimm
nvmem
openrisc
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	PM / reboot: Eliminate race between reboot and suspend	2018-08-06 12:35:20 +02:00
powerpc	powerpc: Document issues with TM on POWER9	2018-07-02 23:54:29 +10:00
pps
process	Raise the minimum required gcc version to 4.6	2018-08-20 14:12:38 -07:00
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	sched/deadline/Documentation: Add overrun signal and GRUB-PA documentation	2018-05-14 09:12:27 +02:00
scsi	block: remove BLK_EH_HANDLED	2018-05-29 08:59:21 -06:00
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	kernel/hung_task.c: allow to set checking interval separately from timeout	2018-08-22 10:52:47 -07:00
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	audit/stable-4.18 PR 20180605	2018-06-06 16:34:00 -07:00
virtual	KVM: X86: Implement "send IPI" hypercall	2018-08-06 17:59:20 +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	Merge branch 'x86-timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2018-08-13 18:28:19 -07:00
xtensa
.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
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_txt.txt
Intel-IOMMU.txt
io_ordering.txt
io-mapping.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
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
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
switchtec.txt
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