fix non-sparseirq architectures.
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Suresh Siddha noticed that we should have a spinlock around it.
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

-tip testing found this lockdep splat:

[    0.000000] Initializing CPU#0
[    0.000000] found new irq_desc for irq 0
[    0.000000] INFO: trying to register non-static key.
[    0.000000] the code is fine but needs lockdep annotation.
[    0.000000] turning off the locking correctness validator.
[    0.000000] Pid: 0, comm: swapper Not tainted 2.6.27-rc3-tip-00191-g98ccb89-dirty #1
[    0.000000]  [<c0153c22>] register_lock_class+0x3d2/0x400
[    0.000000]  [<c0104d87>] ? mcount_call+0x5/0xa
[    0.000000]  [<c0154f3a>] __lock_acquire+0x22a/0x5d0
[    0.000000]  [<c0104d87>] ? mcount_call+0x5/0xa
[    0.000000]  [<c0155351>] lock_acquire+0x71/0xa0
[    0.000000]  [<c016d61f>] ? set_irq_chip+0x3f/0x90
[    0.000000]  [<c070f148>] _spin_lock_irqsave+0x58/0x90
[    0.000000]  [<c016d61f>] ? set_irq_chip+0x3f/0x90
[    0.000000]  [<c016d61f>] set_irq_chip+0x3f/0x90
[    0.000000]  [<c016d7e0>] ? handle_level_irq+0x0/0xe0
[    0.000000]  [<c016da1a>] set_irq_chip_and_handler_name+0x1a/0x40
[    0.000000]  [<c0a396c1>] init_ISA_irqs+0x51/0xa0
[    0.000000]  [<c0a4a365>] pre_intr_init_hook+0x25/0x30
[    0.000000]  [<c0a39723>] native_init_IRQ+0x13/0x370
[    0.000000]  [<c015569c>] ? lock_release+0xcc/0x1d0
[    0.000000]  [<c0104d87>] ? mcount_call+0x5/0xa
[    0.000000]  [<c070dc22>] ? __mutex_unlock_slowpath+0x92/0x110
[    0.000000]  [<c070dcad>] ? mutex_unlock+0xd/0x10
[    0.000000]  [<c0135f62>] ? cpu_maps_update_done+0x12/0x20
[    0.000000]  [<c06c6743>] ? register_cpu_notifier+0x23/0x30
[    0.000000]  [<c011e8ae>] init_IRQ+0xe/0x10
[    0.000000]  [<c0a357a5>] start_kernel+0x1c5/0x340
[    0.000000]  [<c0a35280>] ? unknown_bootoption+0x0/0x210
[    0.000000]  [<c0a3506b>] i386_start_kernel+0x6b/0x80
[    0.000000]  =======================
[    0.000000] found new irq_desc for irq 1
[    0.000000] found new irq_desc for irq 2
[    0.000000] found new irq_desc for irq 3

this:

 static void init_one_irq_desc(struct irq_desc *desc)
 {
         memcpy(desc, &irq_desc_init, sizeof(struct irq_desc));
 #ifdef CONFIG_TRACE_IRQFLAGS
         lockdep_set_class(&desc->lock, &irq_desc_lock_class);
 #endif
 }

should be unconditional.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This has been deprecated for years, the user space irqbalanced utility
works better with numa, has configurable policies, etc...
Signed-off-by: NYinghai Lu <yhlu.kernel@gmai.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

so later don't need compare with -1U
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

change names:

          irq_desc() ==> irq_desc_alloc
	__irq_desc() ==> irq_desc

Also split a few of the uses in lowlevel x86 code.

v2: need to check if desc is null in smp_irq_move_cleanup
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

So we could remove some duplicated calling to irq_desc

v2: make sure irq_desc in  init/main.c is not used without generic_hardirqs
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove irq limit checks - nr_irqs is dynamic and we expand anytime.

v2: fix checking about result irq_cfg_without_new, so could use msi again
v3: use irq_desc_without_new to check irq is valid
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

There are a handful of loops that go from 0 to nr_irqs and use
get_irq_desc() on them. These would allocate all the irq_desc
entries, regardless of the need for them.

Use the smarter for_each_irq_desc() iterator that will only iterate
over the present ones.

v2: make sure arch without GENERIC_HARDIRQS work too
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

add an irq_desc accessor that will not allocate any sparse entry
but returns failure if there's no entry present.
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

based on Eric's patch ...

together mold it with dyn_array for irq_desc, will allcate kstat_irqs for
nr_irq_desc alltogether if needed. -- at that point nr_cpus is known already.

v2: make sure system without generic_hardirqs works they don't have irq_desc
v3: fix merging
v4: [mingo@elte.hu] fix typo

[ mingo@elte.hu ] irq: build fix

fix:

 arch/x86/xen/spinlock.c: In function 'xen_spin_lock_slow':
 arch/x86/xen/spinlock.c:90: error: 'struct kernel_stat' has no member named 'irqs'
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

fix:

[   10.631533] calling  yenta_socket_init+0x0/0x20
[   10.631533] Yenta: CardBus bridge found at 0000:15:00.0 [17aa:2012]
[   10.631533] Yenta: Using INTVAL to route CSC interrupts to PCI
[   10.631533] Yenta: Routing CardBus interrupts to PCI
[   10.631533] Yenta TI: socket 0000:15:00.0, mfunc 0x01d01002, devctl 0x64
[   10.731599] BUG: unable to handle kernel NULL pointer dereference at 00000040
[   10.731838] IP: [<c0c95b5f>] _spin_lock_irq+0xf/0x20
[   10.732221] *pde = 00000000
[   10.732741] Oops: 0002 [#1] SMP
[   10.733453]
[   10.734253] Pid: 1, comm: swapper Tainted: G        W (2.6.27-rc3-tip-00173-gd7eaa4f-dirty #1)
[   10.735188] EIP: 0060:[<c0c95b5f>] EFLAGS: 00010002 CPU: 0
[   10.735523] EIP is at _spin_lock_irq+0xf/0x20
[   10.735523] EAX: 00000040 EBX: 00000000 ECX: f6e04c90 EDX: 00000100
[   10.735523] ESI: 000000df EDI: f6e04c90 EBP: f7867df0 ESP: f7867df0
[   10.735523]  DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
[   10.735523] Process swapper (pid: 1, ti=f7867000 task=f7870000 task.ti=f7867000)
[   10.735523] Stack: f7867e04 c0155fbd 00000000 00000000 f6e04c90 f7867e5c c0c6e319 c0f6a074
[   10.735523]        f6e04c90 000017aa 00002012 c112b648 f791f240 c112b5e0 f7867e44 c010440b
[   10.735523]        f791f240 f791f29c c112b8ec f791f240 00000000 f7867e5c c048f893 03c0b648
[   10.735523] Call Trace:
[   10.735523]  [<c0155fbd>] ? probe_irq_on+0x3d/0x140
[   10.735523]  [<c0c6e319>] ? yenta_probe+0x529/0x640
[   10.735523]  [<c010440b>] ? mcount_call+0x5/0xa
[   10.735523]  [<c048f893>] ? pci_match_device+0xa3/0xb0
[   10.735523]  [<c048fc1e>] ? pci_device_probe+0x5e/0x80
[   10.735523]  [<c0515423>] ? driver_probe_device+0x83/0x180
[   10.735523]  [<c0515594>] ? __driver_attach+0x74/0x80
[   10.735523]  [<c0514b69>] ? bus_for_each_dev+0x49/0x70
[   10.735523]  [<c051528e>] ? driver_attach+0x1e/0x20
[   10.735523]  [<c0515520>] ? __driver_attach+0x0/0x80
[   10.735523]  [<c05150d3>] ? bus_add_driver+0x1a3/0x220
[   10.735523]  [<c048fb60>] ? pci_device_remove+0x0/0x40
[   10.735523]  [<c05157f4>] ? driver_register+0x54/0x130
[   10.735523]  [<c048fe2f>] ? __pci_register_driver+0x4f/0x90
[   10.735523]  [<c11e9419>] ? yenta_socket_init+0x19/0x20
[   10.735523]  [<c0101125>] ? do_one_initcall+0x35/0x160
[   10.735523]  [<c11e9400>] ? yenta_socket_init+0x0/0x20
[   10.735523]  [<c01391a6>] ? __queue_work+0x36/0x50
[   10.735523]  [<c013922d>] ? queue_work_on+0x3d/0x50
[   10.735523]  [<c11a2758>] ? kernel_init+0x148/0x210
[   10.735523]  [<c11a2610>] ? kernel_init+0x0/0x210
[   10.735523]  [<c01043f3>] ? kernel_thread_helper+0x7/0x10
[   10.735523]  =======================
[   10.735523] Code: 10 38 f2 74 06 f3 90 8a 10 eb f6 5d 89 c8 c3 8d b6 00 00 00 00 8d bc 27 00 00 00 00 55 89 e5 e8 a4 e8 46 ff fa ba 00 01 00 00 90 <66> 0f c1 10 38 f2 74 06 f3 90 8a 10 eb f6 5d c3 90 55 89 e5 53

as auto-probing wants to iterate over existing irqs.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

add CONFIG_HAVE_SPARSE_IRQ to for use condensed array.
Get rid of irq_desc[] array assumptions.

Preallocate 32 irq_desc, and irq_desc() will try to get more.

( No change in functionality is expected anywhere, except the odd build
  failure where we missed a code site or where a crossing commit itroduces
  new irq_desc[] usage. )

v2: according to Eric, change get_irq_desc() to irq_desc()
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

fix:

  Building modules, stage 2.
  MODPOST 458 modules
  ERROR: "nr_irqs" [drivers/serial/8250.ko] undefined!
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

at this point nr_irqs is equal NR_IRQS

convert a few easy users from NR_IRQS to dynamic nr_irqs.

v2: according to Eric, we need to take care of arch without generic_hardirqs
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Various people outside the tty layer still stick their noses in behind the
scenes. We need to make sure they also obey the locking and referencing rules.
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This is pure tty code so put it in the tty layer where it can be with the
locking relevant material it uses
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Introduce a kref to the tty structure and use it to protect the tty->signal
tty references. For now we don't introduce it for anything else.
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

After commit 831830b5 aka
"restrict reading from /proc/<pid>/maps to those who share ->mm or can ptrace"
sysctl stopped being relevant because commit moved security checks from ->show
time to ->start time (mm_for_maps()).
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Acked-by: NKees Cook <kees.cook@canonical.com>

lock_task_sighand() make sure task->sighand is being protected,
so we do not need rcu_read_lock().
[ exec() will get task->sighand->siglock before change task->sighand! ]

But code using rcu_read_lock() _just_ to protect lock_task_sighand()
only appear in procfs. (and some code in procfs use lock_task_sighand()
without such redundant protection.)

Other subsystem may put lock_task_sighand() into rcu_read_lock()
critical region, but these rcu_read_lock() are used for protecting
"for_each_process()", "find_task_by_vpid()" etc. , not for protecting
lock_task_sighand().
Signed-off-by: NLai Jiangshan <laijs@cn.fujitsu.com>
[ok from Oleg]
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>

export get_cpu_idle_time_us() for it to be used in ondemand governor.
Last update time can be current time when the CPU is currently non-idle,
accounting for the busy time since last idle.
Signed-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NDave Jones <davej@redhat.com>

add /proc/sys/kernel/sched_domain/cpu0/domain0/name, to make
it easier to see which specific scheduler domain remained at
that entry.

Since we process the scheduler domain tree and
simplify it, it's not always immediately clear during debugging
which domain came from where.

depends on CONFIG_SCHED_DEBUG=y.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

While looking at the code I wondered why we always do:

  sync && avg_overlap < migration_cost

Which is a bit odd, since the overlap test was meant to detect sync wakeups
so using it to specialize sync wakeups doesn't make much sense.

Hence change the code to do:

  sync || avg_overlap < migration_cost
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The softlockup watchdog needs to be touched when resuming the from the
kgdb stopped state to avoid the printk that a CPU is stuck if the
debugger was active for longer than the softlockup threshold.
Signed-off-by: NJason Wessel <jason.wessel@windriver.com>

css will be initialized by cgroup core.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Acked-by: NPeter Zijlstra <peterz@infradead.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

While working on the new version of the code for SCHED_SPORADIC I
noticed something strange in the present throttling mechanism. More
specifically in the throttling timer handler in sched_rt.c
(do_sched_rt_period_timer()) and in rt_rq_enqueue().

The problem is that, when unthrottling a runqueue, rt_rq_enqueue() only
asks for rescheduling if the runqueue has a sched_entity associated to
it (i.e., rt_rq->rt_se != NULL).
Now, if the runqueue is the root rq (which has a rt_se = NULL)
rescheduling does not take place, and it is delayed to some undefined
instant in the future.

This imply some random bandwidth usage by the RT tasks under throttling.
For instance, setting rt_runtime_us/rt_period_us = 950ms/1000ms an RT
task will get less than 95%. In our tests we got something varying
between 70% to 95%.
Using smaller time values, e.g., 95ms/100ms, things are even worse, and
I can see values also going down to 20-25%!!

The tests we performed are simply running 'yes' as a SCHED_FIFO task,
and checking the CPU usage with top, but we can investigate thoroughly
if you think it is needed.

Things go much better, for us, with the attached patch... Don't know if
it is the best approach, but it solved the issue for us.
Signed-off-by: NDario Faggioli <raistlin@linux.it>
Signed-off-by: NMichael Trimarchi <trimarchimichael@yahoo.it>
Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: <stable@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: jiffies increment too fast.

Hugh Dickins noted that with NOHZ=n and HIGHRES=n jiffies get
incremented too fast. The reason is a wrong check in the broadcast
enter/exit code, which keeps the local apic timer in periodic mode
when the switch happens.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

This fixes a warning on latest -tip:

 kernel/cpuset.c: Dans la fonction «scan_for_empty_cpusets» :
 kernel/cpuset.c:1932: attention : passing argument 1 of «list_add_tail» discards qualifiers from pointer target type

Actually the struct cpuset *root passed in parameter to scan_for_empty_cpusets
is not supposed to be const since an entry is added on the tail of its list.
Just correct the qualifier.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

fix the !CONFIG_RCU_CPU_STALL_DETECTOR path:

 kernel/rcuclassic.c: In function '__rcu_pending':
 kernel/rcuclassic.c:609: error: too few arguments to function 'check_cpu_stall'
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This patch adds stalled-CPU detection to Classic RCU.  This capability
is enabled by a new config variable CONFIG_RCU_CPU_STALL_DETECTOR, which
defaults disabled.

This is a debugging feature to detect infinite loops in kernel code, not
something that non-kernel-hackers would be expected to care about.

This feature can detect looping CPUs in !PREEMPT builds and looping CPUs
with preemption disabled in PREEMPT builds.  This is essentially a port of
this functionality from the treercu patch, replacing the stall debug patch
that is already in tip/core/rcu (commit 67182ae1).

The changes from the patch in tip/core/rcu include making the config
variable name match that in treercu, changing from seconds to jiffies to
avoid spurious warnings, and printing a boot message when this feature
is enabled.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Found by static checker (http://repo.or.cz/w/smatch.git).
Signed-off-by: NDan Carpenter <error27@gmail.com>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Genirq hasn't previously recorded the trigger type used by any given IRQ,
although some irq_chip support has done so.  That data can be useful when
troubleshooting.  This patch records it in the relevant irq_desc.status
bits, and improves consistency between the two driver-visible calls
affected:

 - Make set_irq_type() usage match request_irq() usage:
    * IRQ_TYPE_NONE should be a NOP; succeed, so irq_chip methods
      won't have to handle that case any more (many do it wrong).
    * IRQ_TYPE_PROBE is ignored; any buggy out-of-tree callers
      might need to switch over to the real IRQ probing code.
    * emit the same diagnostics (from shared utility code)

 - Their kerneldoc now reflects usage:
    * request_irq() flags include IRQF_TRIGGER_* to specify
      active edge(s)/level ... docs previously omitted that
    * set_irq_type() is declared in <linux/irq.h> so callers
      should use the (bit-equivalent) IRQ_TYPE_* symbols there

Also: adds a warning about shared IRQs that don't end up using the
requested trigger mode; and fix an unrelated "sparse" warning.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This patch does following:
o Removes unused variable and argument "rq".
o Optimizes one of the "if" conditions in wake_affine() - i.e.  if
  "balanced" is true, we need not do rest of the calculations in the
  condition.
o If this cpu is same as the previous cpu (on which woken up task
  was running when it went to sleep), no need to call wake_affine at all.
Signed-off-by: NAmit K Arora <aarora@linux.vnet.ibm.com>
Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This patch adds the CONFIG_FILE_LOCKING option which allows to remove
support for advisory locks. With this patch enabled, the flock()
system call, the F_GETLK, F_SETLK and F_SETLKW operations of fcntl()
and NFS support are disabled. These features are not necessarly needed
on embedded systems. It allows to save ~11 Kb of kernel code and data:

   text          data     bss     dec     hex filename
1125436        118764  212992 1457192  163c28 vmlinux.old
1114299        118564  212992 1445855  160fdf vmlinux
 -11137    -200       0  -11337   -2C49 +/-

This patch has originally been written by Matt Mackall
<mpm@selenic.com>, and is part of the Linux Tiny project.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: NMatt Mackall <mpm@selenic.com>
Cc: matthew@wil.cx
Cc: linux-fsdevel@vger.kernel.org
Cc: mpm@selenic.com
Cc: akpm@linux-foundation.org
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

There's a race between mm->owner assignment and swapoff, more easily
seen when task slab poisoning is turned on.  The condition occurs when
try_to_unuse() runs in parallel with an exiting task.  A similar race
can occur with callers of get_task_mm(), such as /proc/<pid>/<mmstats>
or ptrace or page migration.

CPU0                                    CPU1
                                        try_to_unuse
                                        looks at mm = task0->mm
                                        increments mm->mm_users
task 0 exits
mm->owner needs to be updated, but no
new owner is found (mm_users > 1, but
no other task has task->mm = task0->mm)
mm_update_next_owner() leaves
                                        mmput(mm) decrements mm->mm_users
task0 freed
                                        dereferencing mm->owner fails

The fix is to notify the subsystem via mm_owner_changed callback(),
if no new owner is found, by specifying the new task as NULL.

Jiri Slaby:
mm->owner was set to NULL prior to calling cgroup_mm_owner_callbacks(), but
must be set after that, so as not to pass NULL as old owner causing oops.

Daisuke Nishimura:
mm_update_next_owner() may set mm->owner to NULL, but mem_cgroup_from_task()
and its callers need to take account of this situation to avoid oops.

Hugh Dickins:
Lockdep warning and hang below exec_mmap() when testing these patches.
exit_mm() up_reads mmap_sem before calling mm_update_next_owner(),
so exec_mmap() now needs to do the same.  And with that repositioning,
there's now no point in mm_need_new_owner() allowing for NULL mm.
Reported-by: NHugh Dickins <hugh@veritas.com>
Signed-off-by: NBalbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: NJiri Slaby <jirislaby@gmail.com>
Signed-off-by: NDaisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Signed-off-by: NHugh Dickins <hugh@veritas.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Paul Menage <menage@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Impact: per CPU hrtimers can be migrated from a dead CPU

The hrtimer code has no knowledge about per CPU timers, but we need to
prevent the migration of such timers and warn when such a timer is
active at migration time.

Explicitely mark the timers as per CPU and use a more understandable
mode descriptor for the interrupts safe unlocked callback mode, which
is used by hrtimer_sleeper and the scheduler code.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Impact: during migration active hrtimers can be seen as inactive

The migration code removes the hrtimers from the queues of the dead
CPU and sets the state temporary to INACTIVE. The enqueue code sets it
to ACTIVE/PENDING again.

Prevent that the wrong state can be seen by using a separate migration
state bit.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Impact: Stale timers after a CPU went offline.

commit 37bb6cb4
       hrtimer: unlock hrtimer_wakeup

changed the hrtimer sleeper callback mode to CB_IRQSAFE_NO_SOFTIRQ due
to locking problems. A result of this change is that when enqueue is
called for an already expired hrtimer the callback function is not
longer called directly from the enqueue code. The normal callers have
been fixed in the code, but the migration code which moves hrtimers
from a dead CPU to a live CPU was not made aware of this.

This can be fixed by checking the timer state after the call to
enqueue in the migration code.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>