Tetsuo Handa 780cbcf287 kernel/hung_task.c: defer showing held locks ... When I was running my testcase which may block hundreds of threads on fs locks, I got lockup due to output from debug_show_all_locks() added by commit b2d4c2edb2 ("locking/hung_task: Show all locks"). For example, if 1000 threads were blocked in TASK_UNINTERRUPTIBLE state and 500 out of 1000 threads hold some lock, debug_show_all_locks() from for_each_process_thread() loop will report locks held by 500 threads for 1000 times. This is a too much noise. In order to make sure rcu_lock_break() is called frequently, we should avoid calling debug_show_all_locks() from for_each_process_thread() loop because debug_show_all_locks() effectively calls for_each_process_thread() loop. Let's defer calling debug_show_all_locks() till before panic() or leaving for_each_process_thread() loop. Link: http://lkml.kernel.org/r/1489296834-60436-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reviewed-by: Vegard Nossum <vegard.nossum@oracle.com> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2017-05-08 17:15:10 -07:00
..
bpf	bpf: enhance verifier to understand stack pointer arithmetic	2017-05-01 11:40:23 -04:00
cgroup	Merge branch 'for-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup	2017-05-01 13:52:24 -07:00
configs	config: android-base: enable hardened usercopy and kernel ASLR	2017-02-27 18:43:46 -08:00
debug	sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h>	2017-03-02 08:42:34 +01:00
events	Merge branch 'perf/urgent' into perf/core, to pick up fixes	2017-03-28 07:44:25 +02:00
gcov	…
irq	Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2017-05-01 15:46:13 -07:00
livepatch	Merge branches 'for-4.12/upstream' and 'for-4.12/klp-hybrid-consistency-model' into for-linus	2017-05-01 21:49:28 +02:00
locking	Merge branch 'akpm' (patches from Andrew)	2017-05-03 17:55:59 -07:00
power	Merge branch 'WIP.sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2017-03-03 10:16:38 -08:00
printk	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk	2017-05-03 18:29:28 -07:00
rcu	rcu/tracing: Add rcu_disabled to denote when rcu_irq_enter() will not work	2017-04-10 15:22:03 -04:00
sched	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial	2017-05-02 19:09:35 -07:00
time	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace	2017-05-05 11:08:43 -07:00
trace	New features for this release:	2017-05-03 18:41:21 -07:00
.gitignore	…
Kconfig.freezer	…
Kconfig.hz	…
Kconfig.locks	locking/mutex: Allow MUTEX_SPIN_ON_OWNER when DEBUG_MUTEXES	2016-10-25 11:31:51 +02:00
Kconfig.preempt	…
Makefile	cgroup: move cgroup files under kernel/cgroup/	2016-12-27 14:49:05 -05:00
acct.c	sched/headers: Prepare to move cputime functionality from <linux/sched.h> into <linux/sched/cputime.h>	2017-03-02 08:42:39 +01:00
async.c	…
audit.c	Merge branch 'stable-4.12' of git://git.infradead.org/users/pcmoore/audit	2017-05-03 09:21:59 -07:00
audit.h	audit: Use timespec64 to represent audit timestamps	2017-05-02 10:16:05 -04:00
audit_fsnotify.c	Merge branch 'fsnotify' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs	2017-05-03 11:05:15 -07:00
audit_tree.c	Merge branch 'fsnotify' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs	2017-05-03 11:05:15 -07:00
audit_watch.c	Merge branch 'fsnotify' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs	2017-05-03 11:05:15 -07:00
auditfilter.c	audit: kernel generated netlink traffic should have a portid of 0	2017-05-02 10:16:05 -04:00
auditsc.c	Merge branch 'fsnotify' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs	2017-05-03 11:05:15 -07:00
backtracetest.c	…
bounds.c	…
capability.c	capability: export has_capability	2017-01-12 07:01:56 -07:00
compat.c	time: Change k_clock nsleep() to use timespec64	2017-04-14 21:49:56 +02:00
configs.c	Replace <asm/uaccess.h> with <linux/uaccess.h> globally	2016-12-24 11:46:01 -08:00
context_tracking.c	…
cpu.c	Merge branch 'linus' into locking/core, to pick up fixes	2017-04-14 10:29:40 +02:00
cpu_pm.c	…
crash_dump.c	…
cred.c	sched/headers: Prepare for new header dependencies before moving code to <linux/sched/coredump.h>	2017-03-02 08:42:28 +01:00
delayacct.c	sched/headers: Prepare to move cputime functionality from <linux/sched.h> into <linux/sched/cputime.h>	2017-03-02 08:42:39 +01:00
dma.c	…
elfcore.c	…
exec_domain.c	…
exit.c	userfaultfd: non-cooperative: rollback userfaultfd_exit	2017-03-09 17:01:09 -08:00
extable.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next	2017-02-22 10:15:09 -08:00
fork.c	Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security	2017-05-03 08:50:52 -07:00
freezer.c	…
futex.c	futex: Clarify mark_wake_futex memory barrier usage	2017-04-15 16:03:46 +02:00
futex_compat.c	Replace <asm/uaccess.h> with <linux/uaccess.h> globally	2016-12-24 11:46:01 -08:00
groups.c	Replace <asm/uaccess.h> with <linux/uaccess.h> globally	2016-12-24 11:46:01 -08:00
hung_task.c	kernel/hung_task.c: defer showing held locks	2017-05-08 17:15:10 -07:00
irq_work.c	…
jump_label.c	This release has no new tracing features, just clean ups, minor fixes	2017-02-27 13:26:17 -08:00
kallsyms.c	bpf: make jited programs visible in traces	2017-02-17 13:40:05 -05:00
kcmp.c	…
kcov.c	kcov: make kcov work properly with KASLR enabled	2016-12-20 09:48:47 -08:00
kexec.c	…
kexec_core.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk	2017-02-22 17:33:34 -08:00
kexec_file.c	kexec, x86/purgatory: Unbreak it and clean it up	2017-03-10 20:55:09 +01:00
kexec_internal.h	kexec, x86/purgatory: Unbreak it and clean it up	2017-03-10 20:55:09 +01:00
kmod.c	sched/headers, vfs/execve: Prepare to move the do_execve*() prototypes from <linux/sched.h> to <linux/binfmts.h>	2017-03-02 08:42:39 +01:00
kprobes.c	powerpc updates for 4.12 part 1.	2017-05-05 11:36:44 -07:00
ksysfs.c	kernel/ksysfs.c: add __ro_after_init to bin_attribute structure	2017-02-24 17:46:56 -08:00
kthread.c	cgroup, kthread: close race window where new kthreads can be migrated to non-root cgroups	2017-03-17 10:18:47 -04:00
latencytop.c	sched/headers: Prepare to move sched_info_on() and force_schedstat_enabled() from <linux/sched.h> to <linux/sched/stat.h>	2017-03-02 08:42:39 +01:00
membarrier.c	Fix: Disable sys_membarrier when nohz_full is enabled	2017-01-23 11:32:16 -08:00
memremap.c	mm, zone_device: Replace {get, put}_zone_device_page() with a single reference to fix pmem crash	2017-05-01 09:15:53 +02:00
module-internal.h	…
module.c	Modules updates for v4.12	2017-05-03 19:12:27 -07:00
module_signing.c	…
notifier.c	kernel/notifier.c: simplify expression	2017-02-24 17:46:56 -08:00
nsproxy.c	perf: Add PERF_RECORD_NAMESPACES to include namespaces related info	2017-03-13 15:57:41 -03:00
padata.c	padata: get_next is never NULL	2017-04-21 20:30:46 +08:00
panic.c	sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h>	2017-03-02 08:42:34 +01:00
params.c	boot/param: Move next_arg() function to lib/cmdline.c for later reuse	2017-04-18 10:37:13 +02:00
pid.c	sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task.h>	2017-03-02 08:42:35 +01:00
pid_namespace.c	sched/headers: Prepare for the reduction of <linux/sched.h>'s signal API dependency	2017-03-02 08:42:37 +01:00
profile.c	sched/headers: Prepare to move sched_info_on() and force_schedstat_enabled() from <linux/sched.h> to <linux/sched/stat.h>	2017-03-02 08:42:39 +01:00
ptrace.c	ptrace: fix PTRACE_LISTEN race corrupting task->state	2017-04-08 00:47:48 -07:00
range.c	…
reboot.c	…
relay.c	Merge branch 'work.splice' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2017-05-02 11:38:06 -07:00
resource.c	…
seccomp.c	sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task_stack.h>	2017-03-02 08:42:36 +01:00
signal.c	signal: Make kill_proc_info static	2017-04-21 22:46:25 -05:00
smp.c	sched/headers: Prepare for new header dependencies before moving code to <linux/sched/idle.h>	2017-03-02 08:42:26 +01:00
smpboot.c	sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task.h>	2017-03-02 08:42:35 +01:00
smpboot.h	…
softirq.c	sched/core: Remove 'task' parameter and rename tsk_restore_flags() to current_restore_flags()	2017-04-11 09:06:32 +02:00
stacktrace.c	stacktrace/x86: add function for detecting reliable stack traces	2017-03-08 09:18:02 +01:00
stop_machine.c	locking/core, stop_machine: Yield the CPU during stop machine()	2016-11-16 10:15:09 +01:00
sys.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace	2017-05-05 11:08:43 -07:00
sys_ni.c	move aio compat to fs/aio.c	2016-12-22 22:58:37 -05:00
sysctl.c	proc/sysctl: fix the int overflow for jiffies conversion	2017-05-08 17:15:10 -07:00
sysctl_binary.c	net: Remove NET_CORE_BUDGET_USECS from sysctl binary interface.	2017-04-21 15:59:52 -04:00
task_work.c	…
taskstats.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net	2016-11-15 10:54:36 -05:00
test_kprobes.c	…
torture.c	sched/headers: Prepare for new header dependencies before moving code to <linux/sched/clock.h>	2017-03-02 08:42:27 +01:00
tracepoint.c	sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task.h>	2017-03-02 08:42:35 +01:00
tsacct.c	sched/headers: Prepare to move cputime functionality from <linux/sched.h> into <linux/sched/cputime.h>	2017-03-02 08:42:39 +01:00
ucount.c	ucount: Remove the atomicity from ucount->count	2017-03-06 15:26:37 -06:00
uid16.c	sched/headers: Prepare to remove <linux/cred.h> inclusion from <linux/sched.h>	2017-03-02 08:42:31 +01:00
up.c	smp: Add function to execute a function synchronously on a CPU	2016-09-05 13:52:39 +02:00
user-return-notifier.c	…
user.c	sched/headers: Prepare for new header dependencies before moving code to <linux/sched/user.h>	2017-03-02 08:42:29 +01:00
user_namespace.c	sched/headers: Prepare for new header dependencies before moving code to <linux/sched/signal.h>	2017-03-02 08:42:29 +01:00
utsname.c	sched/headers: Prepare to move the task_lock()/unlock() APIs to <linux/sched/task.h>	2017-03-02 08:42:38 +01:00
utsname_sysctl.c	sched/headers: Remove <linux/rwsem.h> from <linux/sched.h>	2017-03-03 01:45:36 +01:00
watchdog.c	sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h>	2017-03-02 08:42:34 +01:00
watchdog_hld.c	sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h>	2017-03-02 08:42:34 +01:00
workqueue.c	Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2017-05-01 19:12:53 -07:00
workqueue_internal.h	…