Tejun Heo 6575820221 workqueue: perform cpu down operations from low priority cpu_notifier() ... Currently, all workqueue cpu hotplug operations run off CPU_PRI_WORKQUEUE which is higher than normal notifiers. This is to ensure that workqueue is up and running while bringing up a CPU before other notifiers try to use workqueue on the CPU. Per-cpu workqueues are supposed to remain working and bound to the CPU for normal CPU_DOWN_PREPARE notifiers. This holds mostly true even with workqueue offlining running with higher priority because workqueue CPU_DOWN_PREPARE only creates a bound trustee thread which runs the per-cpu workqueue without concurrency management without explicitly detaching the existing workers. However, if the trustee needs to create new workers, it creates unbound workers which may wander off to other CPUs while CPU_DOWN_PREPARE notifiers are in progress. Furthermore, if the CPU down is cancelled, the per-CPU workqueue may end up with workers which aren't bound to the CPU. While reliably reproducible with a convoluted artificial test-case involving scheduling and flushing CPU burning work items from CPU down notifiers, this isn't very likely to happen in the wild, and, even when it happens, the effects are likely to be hidden by the following successful CPU down. Fix it by using different priorities for up and down notifiers - high priority for up operations and low priority for down operations. Workqueue cpu hotplug operations will soon go through further cleanup. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: stable@vger.kernel.org Acked-by: "Rafael J. Wysocki" <rjw@sisk.pl>		2012-07-17 12:39:26 -07:00
..
debug	KGDB/KDB regression fixes	2012-04-04 17:26:08 -07:00
events	perf: Use css_tryget() to avoid propping up css refcount	2012-06-18 11:45:57 +02:00
gcov
irq	Merge branches 'irq-urgent-for-linus' and 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2012-06-04 11:36:51 -07:00
power	PM / Hibernate: Use get_gendisk to verify partition if resume_file is integer format	2012-05-18 20:44:59 +02:00
sched	Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2012-06-08 14:59:29 -07:00
time	Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2012-06-15 16:52:35 -07:00
trace	Merge branch 'for-linus' of git://git.kernel.dk/linux-block	2012-07-03 15:45:10 -07:00
.gitignore
acct.c	Merge branch 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2012-01-08 12:19:57 -08:00
async.c	kernel/async: remove redundant declaration.	2012-01-13 09:32:18 +10:30
audit.c	constify path argument of audit_log_d_path()	2012-03-20 21:29:40 -04:00
audit.h
audit_tree.c
audit_watch.c
auditfilter.c
auditsc.c
backtracetest.c
bounds.c
capability.c	userns: Teach inode_capable to understand inodes whose uids map to other namespaces.	2012-05-15 14:59:24 -07:00
cgroup.c	cgroup: fix cgroup hierarchy umount race	2012-07-07 16:08:18 -07:00
cgroup_freezer.c	cgroup: convert all non-memcg controllers to the new cftype interface	2012-04-01 12:09:55 -07:00
compat.c	new helper: sigsuspend()	2012-05-21 23:52:30 -04:00
configs.c
cpu.c	kernel/cpu.c: document clear_tasks_mm_cpumask()	2012-05-31 17:49:30 -07:00
cpu_pm.c	kernel/cpu_pm.c: fix various typos	2012-05-31 17:49:27 -07:00
cpuset.c	Merge branch 'for-3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup	2012-05-22 17:40:19 -07:00
crash_dump.c
cred.c	keys: kill task_struct->replacement_session_keyring	2012-05-23 22:11:41 -04:00
delayacct.c
dma.c
elfcore.c
exec_domain.c
exit.c	pidns: find_new_reaper() can no longer switch to init_pid_ns.child_reaper	2012-06-20 14:39:36 -07:00
extable.c	extable: Skip sorting if sorted at build time.	2012-04-19 15:06:55 -07:00
fork.c	Revert "mm: correctly synchronize rss-counters at exit/exec"	2012-06-07 17:54:07 -07:00
freezer.c
futex.c
futex_compat.c
groups.c	userns: Convert in_group_p and in_egroup_p to use kgid_t	2012-05-03 03:29:33 -07:00
hrtimer.c	Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2011-11-28 08:43:52 -08:00
hung_task.c	hung task debugging: Inject NMI when hung and going to panic	2012-04-25 12:39:25 +02:00
irq_work.c	irq_work: fix compile failure on tile from missing include	2012-04-13 13:15:16 -04:00
itimer.c	itimer: Use printk_once instead of WARN_ONCE	2012-04-10 11:00:30 +02:00
jump_label.c
kallsyms.c	vsprintf: fix %ps on non symbols when using kallsyms	2012-05-29 16:22:32 -07:00
kcmp.c	syscalls, x86: add __NR_kcmp syscall	2012-05-31 17:49:32 -07:00
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
kexec.c
kfifo.c
kmod.c	kmod.c: fix kernel-doc warning	2012-05-31 17:49:28 -07:00
kprobes.c
ksysfs.c
kthread.c
latencytop.c	kernel: Map most files to use export.h instead of module.h	2011-10-31 09:20:12 -04:00
lglock.c	brlocks/lglocks: turn into functions	2012-05-29 23:28:41 -04:00
lockdep.c
lockdep_internals.h
lockdep_proc.c
lockdep_states.h
Makefile	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2012-06-01 10:34:35 -07:00
module.c	Guard check in module loader against integer overflow	2012-05-23 22:28:53 +09:30
mutex-debug.c	kernel: Map most files to use export.h instead of module.h	2011-10-31 09:20:12 -04:00
mutex-debug.h	mutex: Use p->on_cpu for the adaptive spin	2011-04-14 08:52:33 +02:00
mutex.c	sched/rt: Use schedule_preempt_disabled()	2012-03-01 10:28:03 +01:00
mutex.h
notifier.c
nsproxy.c
padata.c	padata: Fix cpu hotplug	2012-03-29 19:52:46 +08:00
panic.c	kdump: Execute kmsg_dump(KMSG_DUMP_PANIC) after smp_send_stop()	2012-05-18 14:02:10 +02:00
params.c	params: replace printk(KERN_<LVL>...) with pr_<lvl>(...)	2012-05-04 17:28:18 -07:00
pid.c	mm: add a low limit to alloc_large_system_hash	2012-05-24 00:28:21 -04:00
pid_namespace.c	pidns: guarantee that the pidns init will be the last pidns process reaped	2012-06-20 14:39:36 -07:00
posix-cpu-timers.c	[S390] cputime: add sparse checking and cleanup	2011-12-15 14:56:19 +01:00
posix-timers.c	kernel: Map most files to use export.h instead of module.h	2011-10-31 09:20:12 -04:00
printk.c	kmsg: merge continuation records while printing	2012-07-09 12:15:42 -07:00
profile.c
ptrace.c	userns: Convert ptrace, kill, set_priority permission checks to work with kuids and kgids	2012-05-03 03:28:51 -07:00
range.c	range: fix bogus misuse of module.h to get printk()	2011-10-31 09:20:11 -04:00
rcu.h	rcu: Allow nesting of rcu_idle_enter() and rcu_idle_exit()	2012-02-21 09:06:12 -08:00
rcupdate.c	rcu: Make exit_rcu() more precise and consolidate	2012-05-02 14:48:27 -07:00
rcutiny.c
rcutiny_plugin.h	rcu: Make exit_rcu() more precise and consolidate	2012-05-02 14:48:27 -07:00
rcutorture.c
rcutree.c	rcu: Stop rcu_do_batch() from multiplexing the "count" variable	2012-06-25 12:35:25 -07:00
rcutree.h	rcu: Move RCU_FAST_NO_HZ per-CPU variables to rcu_dynticks structure	2012-06-06 20:43:28 -07:00
rcutree_plugin.h	rcu: Precompute RCU_FAST_NO_HZ timer offsets	2012-06-06 20:43:28 -07:00
rcutree_trace.c	rcu: Make rcu_barrier() less disruptive	2012-05-09 14:27:54 -07:00
relay.c	splice: fix racy pipe->buffers uses	2012-06-13 21:16:42 +02:00
res_counter.c	rescounters: add res_counter_uncharge_until()	2012-05-29 16:22:27 -07:00
resource.c	kernel/resource.c: correct the comment of allocate_resource()	2012-05-31 17:49:26 -07:00
rtmutex-debug.c	lockdep, rtmutex, bug: Show taint flags on error	2011-12-06 08:16:49 +01:00
rtmutex-debug.h	[PATCH] lockdep: better lock debugging	2006-07-03 15:27:01 -07:00
rtmutex-tester.c	rtmutex-tester: convert sysdev_class to a regular subsystem	2011-12-14 14:54:22 -08:00
rtmutex.c	Revert "rcu: Permit rt_mutex_unlock() with irqs disabled"	2011-12-11 10:33:18 -08:00
rtmutex.h	[PATCH] lockdep: better lock debugging	2006-07-03 15:27:01 -07:00
rtmutex_common.h	rtmutex: Simplify PI algorithm and make highest prio task get lock	2011-01-27 21:13:51 -05:00
rwsem.c
seccomp.c
semaphore.c	semaphore: fix improper comment reference to mutex	2012-04-05 17:15:55 -07:00
signal.c	new helper: signal_delivered()	2012-06-01 12:58:52 -04:00
smp.c	smp: Implement kick_all_cpus_sync()	2012-05-08 12:35:06 +02:00
smpboot.c	smpboot, idle: Fix comment mismatch over idle_threads_init()	2012-05-24 22:58:08 +02:00
smpboot.h	smp: Fix idle_thread_init() inline stub	2012-05-04 12:52:25 +02:00
softirq.c
spinlock.c	locking/kconfig: Simplify INLINE_SPIN_UNLOCK usage	2012-03-23 13:18:57 +01:00
srcu.c	rcu: Implement per-domain single-threaded call_srcu() state machine	2012-04-30 10:48:25 -07:00
stacktrace.c	kernel: Map most files to use export.h instead of module.h	2011-10-31 09:20:12 -04:00
stop_machine.c
sys.c	c/r: prctl: less paranoid prctl_set_mm_exe_file()	2012-07-11 16:04:43 -07:00
sys_ni.c	syscalls, x86: add __NR_kcmp syscall	2012-05-31 17:49:32 -07:00
sysctl.c	sysctl: fix write access to dmesg_restrict/kptr_restrict	2012-04-05 14:51:43 +10:00
sysctl_binary.c	binary_sysctl(): fix memory leak	2011-12-20 10:25:04 -08:00
task_work.c	task_work_add: generic process-context callbacks	2012-05-23 22:09:21 -04:00
taskstats.c	Make TASKSTATS require root access	2011-09-19 17:04:37 -07:00
test_kprobes.c
time.c
timeconst.pl
timer.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace	2012-05-23 17:42:39 -07:00
tracepoint.c	static keys: Introduce 'struct static_key', static_key_true()/false() and static_key_slow_[inc|dec]()	2012-02-24 10:05:59 +01:00
tsacct.c
uid16.c	userns: Convert setting and getting uid and gid system calls to use kuid and kgid	2012-05-03 03:28:41 -07:00
up.c
user-return-notifier.c	kernel: Map most files to use export.h instead of module.h	2011-10-31 09:20:12 -04:00
user.c	userns: Silence silly gcc warning.	2012-05-19 15:44:40 -06:00
user_namespace.c	userns: Store uid and gid values in struct cred with kuid_t and kgid_t types	2012-05-03 03:28:38 -07:00
utsname.c	userns: Use cred->user_ns instead of cred->user->user_ns	2012-04-07 16:55:51 -07:00
utsname_sysctl.c	Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux	2011-11-06 19:44:47 -08:00
wait.c
watchdog.c	watchdog: Quiet down the boot messages	2012-06-14 12:20:50 +02:00
workqueue.c	workqueue: perform cpu down operations from low priority cpu_notifier()	2012-07-17 12:39:26 -07:00
workqueue_sched.h	workqueue: implement concurrency managed dynamic worker pool	2010-06-29 10:07:14 +02:00