Mandeep Singh Baines ce9dbe244b softlockup: check all tasks in hung_task ...

Impact: extend the scope of hung-task checks

Changed the default value of hung_task_check_count to PID_MAX_LIMIT.
hung_task_batch_count added to put an upper bound on the critical
section. Every hung_task_batch_count checks, the rcu lock is never
held for a too long time.

Keeping the critical section small minimizes time preemption is disabled
and keeps rcu grace periods small.

To prevent following a stale pointer, get_task_struct is called on g and t.
To verify that g and t have not been unhashed while outside the critical
section, the task states are checked.

The design was proposed by Frédéric Weisbecker.

Signed-off-by: Mandeep Singh Baines <msb@google.com>
Suggested-by: Frédéric Weisbecker <fweisbec@gmail.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

2009-02-05 19:54:57 +01:00

..

irq

async: Asynchronous function calls to speed up kernel boot

2009-01-07 08:45:46 -08:00

power

Merge branch 'linus' into release

2009-01-09 03:39:43 -05:00

time

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial

2009-01-07 11:31:52 -08:00

trace

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rric/oprofile

2009-01-09 12:43:06 -08:00

.gitignore

…

acct.c

CRED: Wrap task credential accesses in the core kernel

2008-11-14 10:39:12 +11:00

async.c

async: fix __lowest_in_progress()

2009-01-12 16:39:58 -08:00

audit_tree.c

audit: validate comparison operations, store them in sane form

2009-01-04 15:14:42 -05:00

audit.c

[PATCH] fix broken timestamps in AVC generated by kernel threads

2008-12-09 02:27:41 -05:00

audit.h

fixing audit rule ordering mess, part 1

2009-01-04 15:14:41 -05:00

auditfilter.c

audit: validate comparison operations, store them in sane form

2009-01-04 15:14:42 -05:00

auditsc.c

make sure that filterkey of task,always rules is reported

2009-01-04 15:14:42 -05:00

backtracetest.c

…

bounds.c

…

capability.c

Merge branch 'next' into for-linus

2009-01-07 09:58:22 +11:00

cgroup_debug.c

cgroups: fix probable race with put_css_set[_taskexit] and find_css_set

2008-10-20 08:52:38 -07:00

cgroup_freezer.c

freezer_cg: disable writing freezer.state of root cgroup

2008-11-12 17:17:16 -08:00

cgroup.c

cgroups: add css_tryget()

2009-01-08 08:31:10 -08:00

compat.c

Allow times and time system calls to return small negative values

2009-01-06 15:59:13 -08:00

configs.c

kernel/configs.c: remove useless comments

2008-10-20 08:52:34 -07:00

cpu.c

stop_machine/cpu hotplug: fix disable_nonboot_cpus

2009-01-07 11:36:14 -08:00

cpuset.c

cpuset: remove remaining pointers to cpumask_t

2009-01-08 08:31:11 -08:00

cred-internals.h

CRED: Inaugurate COW credentials

2008-11-14 10:39:23 +11:00

cred.c

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6

2009-01-09 13:59:25 -08:00

delayacct.c

schedstat: consolidate per-task cpu runtime stats

2008-12-18 13:54:01 +01:00

dma-coherent.c

dma-coherent: catch oversized requests to dma_alloc_from_coherent()

2009-01-06 15:59:31 -08:00

dma.c

…

exec_domain.c

proc: move /proc/execdomains to kernel/exec_domain.c

2008-10-23 14:30:41 +04:00

exit.c

mm: introduce get_mm_hiwater_xxx(), fix taskstats->hiwater_xxx accounting

2009-01-06 15:59:09 -08:00

extable.c

Merge branch 'core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

2008-12-30 16:10:19 -08:00

fork.c

softlockup: fix to allow compiling with !DETECT_HUNG_TASK

2009-01-16 18:17:34 +01:00

freezer.c

freezer_cg: use thaw_process() in unfreeze_cgroup()

2008-10-30 11:38:45 -07:00

futex_compat.c

CRED: Use RCU to access another task's creds and to release a task's own creds

2008-11-14 10:39:19 +11:00

futex.c

Merge branches 'core/futexes', 'core/locking', 'core/rcu' and 'linus' into core/urgent

2009-01-06 09:32:11 +01:00

hrtimer.c

hrtimer: splitout peek ahead functionality, fix

2009-01-05 14:11:10 +01:00

hung_task.c

softlockup: check all tasks in hung_task

2009-02-05 19:54:57 +01:00

itimer.c

…

kallsyms.c

allow stripping of generated symbols under CONFIG_KALLSYMS_ALL

2008-12-19 22:47:10 +01:00

Kconfig.freezer

container freezer: implement freezer cgroup subsystem

2008-10-20 08:52:34 -07:00

Kconfig.hz

…

Kconfig.preempt

rcu: provide RCU options on non-preempt architectures too

2008-12-25 09:31:28 +01:00

kexec.c

cpumask: prepare for iterators to only go to nr_cpu_ids/nr_cpumask_bits.: core

2009-01-01 10:12:15 +10:30

kfifo.c

…

kgdb.c

…

kmod.c

kmod: fix varargs kernel-doc

2009-01-06 15:59:27 -08:00

kprobes.c

kprobes: support probing module __init function

2009-01-06 15:59:21 -08:00

ksysfs.c

kernel/ksysfs.c:fix dependence on CONFIG_NET

2009-01-06 10:44:31 -08:00

kthread.c

tracepoints: add DECLARE_TRACE() and DEFINE_TRACE()

2008-11-16 09:01:36 +01:00

latencytop.c

KSYM_SYMBOL_LEN fixes

2008-12-10 08:01:54 -08:00

lockdep_internals.h

…

lockdep_proc.c

lockstat: contend with points

2008-10-20 15:43:10 +02:00

lockdep.c

Merge branch 'core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

2008-12-30 16:10:19 -08:00

Makefile

softlockup: decouple hung tasks check from softlockup detection

2009-01-16 14:06:04 +01:00

marker.c

markers/tracpoints: fix non-modular build

2008-11-16 09:52:03 +01:00

module.c

async: Asynchronous function calls to speed up kernel boot

2009-01-07 08:45:46 -08:00

mutex-debug.c

…

mutex-debug.h

…

mutex.c

mutex: __used is needed for function referenced only from inline asm

2008-11-24 10:00:28 +01:00

mutex.h

…

notifier.c

Merge commit 'v2.6.28-rc6' into core/debug

2008-11-26 08:22:50 +01:00

ns_cgroup.c

ns_cgroup: remove unused spinlock

2009-01-08 08:31:02 -08:00

nsproxy.c

User namespaces: set of cleanups (v2)

2008-11-24 18:57:41 -05:00

panic.c

oops: increment the oops UUID every time we oops

2009-01-06 15:59:12 -08:00

params.c

Fix compile warning in kernel/params.c

2008-10-23 12:09:00 -07:00

pid_namespace.c

…

pid.c

pid: generalize task_active_pid_ns

2009-01-08 08:31:12 -08:00

pm_qos_params.c

…

posix-cpu-timers.c

Merge commit 'v2.6.28' into core/core

2008-12-25 13:51:46 +01:00

posix-timers.c

Merge branches 'timers/clocksource', 'timers/hpet', 'timers/hrtimers', 'timers/nohz', 'timers/ntp', 'timers/posixtimers' and 'timers/rtc' into timers/core

2008-12-25 18:02:25 +01:00

printk.c

trivial: printk: fix indentation of new_text_line declaration

2009-01-06 11:28:06 +01:00

profile.c

profile: don't include <asm/ptrace.h> twice.

2009-01-06 15:59:14 -08:00

ptrace.c

Merge branch 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

2008-12-28 12:21:10 -08:00

rcuclassic.c

rcu: add __cpuinit to rcu_init_percpu_data()

2009-01-14 11:26:40 +01:00

rcupdate.c

rcu: eliminate synchronize_rcu_xxx macro

2009-01-05 10:18:08 +01:00

rcupreempt_trace.c

"Tree RCU": scalable classic RCU implementation

2008-12-18 21:56:04 +01:00

rcupreempt.c

rcu: eliminate synchronize_rcu_xxx macro

2009-01-05 10:18:08 +01:00

rcutorture.c

rcu: fix bug in rcutorture system-shutdown code

2009-01-07 23:36:25 +01:00

rcutree_trace.c

"Tree RCU": scalable classic RCU implementation

2008-12-18 21:56:04 +01:00

rcutree.c

rcu: add __cpuinit to rcu_init_percpu_data()

2009-01-14 11:26:40 +01:00

relay.c

relayfs: fix infinite loop with splice()

2008-12-10 08:01:52 -08:00

res_counter.c

memcg: memory cgroup resource counters for hierarchy

2009-01-08 08:31:05 -08:00

resource.c

resource: allow MMIO exclusivity for device drivers

2009-01-07 11:12:32 -08:00

rtmutex_common.h

…

rtmutex-debug.c

…

rtmutex-debug.h

…

rtmutex-tester.c

…

rtmutex.c

…

rtmutex.h

…

rwsem.c

…

sched_clock.c

sched_clock: prevent scd->clock from moving backwards, take #2

2008-12-31 09:53:21 +01:00

sched_cpupri.c

sched: fix section mismatch

2009-01-06 11:07:15 +01:00

sched_cpupri.h

sched: convert struct cpupri_vec cpumask_var_t.

2008-11-24 17:52:22 +01:00

sched_debug.c

sched: partly revert "sched debug: remove NULL checking in print_cfs_rt_rq()"

2009-01-11 02:40:32 +01:00

sched_fair.c

generic swap(): sched: remove local swap() macro

2009-01-08 08:31:15 -08:00

sched_features.h

sched: backward looking buddy

2008-11-05 10:30:14 +01:00

sched_idletask.c

sched: add CONFIG_SMP consistency

2008-10-22 10:01:52 +02:00

sched_rt.c

sched: put back some stack hog changes that were undone in kernel/sched.c

2009-01-03 19:00:09 +01:00

sched_stats.h

Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-cpumask into merge-rr-cpumask

2009-01-03 18:53:31 +01:00

sched.c

kernel/sched.c: add missing forward declaration for 'double_rq_lock'

2009-01-11 13:06:07 +01:00

seccomp.c

…

semaphore.c

…

signal.c

SEND_SIG_NOINFO: set si_pid to tgid instead of pid

2009-01-06 15:59:29 -08:00

smp.c

cpumask: prepare for iterators to only go to nr_cpu_ids/nr_cpumask_bits.: core

2009-01-01 10:12:15 +10:30

softirq.c

Merge branch 'cpus4096-for-linus-3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

2009-01-03 12:04:39 -08:00

softlockup.c

softlockup: decouple hung tasks check from softlockup detection

2009-01-16 14:06:04 +01:00

spinlock.c

…

srcu.c

…

stacktrace.c

stacktrace: provide save_stack_trace_tsk() weak alias

2008-12-25 11:44:43 +01:00

stop_machine.c

stop_machine: introduce stop_machine_create/destroy.

2009-01-05 08:40:14 +10:30

sys_ni.c

reintroduce accept4

2008-11-19 18:49:57 -08:00

sys.c

Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

2009-01-06 17:10:33 -08:00

sysctl_check.c

[XFS] remove restricted chown parameter from xfs linux

2008-10-30 18:30:09 +11:00

sysctl.c

softlockup: decouple hung tasks check from softlockup detection

2009-01-16 14:06:04 +01:00

taskstats.c

cpumask: convert rest of files in kernel/

2009-01-01 10:12:28 +10:30

test_kprobes.c

kprobes: add tests for register_kprobes

2009-01-06 15:59:20 -08:00

time.c

Allow times and time system calls to return small negative values

2009-01-06 15:59:13 -08:00

timeconst.pl

…

timer.c

[PATCH] idle cputime accounting

2008-12-31 15:11:46 +01:00

tracepoint.c

markers/tracpoints: fix non-modular build

2008-11-16 09:52:03 +01:00

tsacct.c

mm: introduce get_mm_hiwater_xxx(), fix taskstats->hiwater_xxx accounting

2009-01-06 15:59:09 -08:00

uid16.c

CRED: Wrap current->cred and a few other accessors

2008-11-14 10:39:18 +11:00

up.c

smp_call_function_single(): be slightly less stupid, fix #2

2009-01-12 16:04:37 +01:00

user_namespace.c

User namespaces: set of cleanups (v2)

2008-11-24 18:57:41 -05:00

user.c

Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

2008-12-28 12:27:58 -08:00

utsname_sysctl.c

sysctl: simplify ->strategy

2008-10-16 11:21:47 -07:00

utsname.c

…

wait.c

…

workqueue.c

cpumask: convert kernel/workqueue.c

2009-01-01 10:12:25 +10:30