10 Jul, 2009
2 commits
-
The timer migration expiry check should prevent the migration of a
timer to another CPU when the timer expires before the next event is
scheduled on the other CPU. Migrating the timer might delay it because
we can not reprogram the clock event device on the other CPU. But the
code implementing that check has two flaws:- for !HIGHRES the check compares the expiry value with the clock
events device expiry value which is wrong for CLOCK_REALTIME based
timers.- the check is racy. It holds the hrtimer base lock of the target CPU,
but the clock event device expiry value can be modified
nevertheless, e.g. by an timer interrupt firing.The !HIGHRES case is easy to fix as we can enqueue the timer on the
cpu which was selected by the load balancer. It runs the idle
balancing code once per jiffy anyway. So the maximum delay for the
timer is the same as when we keep the tick on the current cpu going.In the HIGHRES case we can get the next expiry value from the hrtimer
cpu_base of the target CPU and serialize the update with the cpu_base
lock. This moves the lock section in hrtimer_interrupt() so we can set
next_event to KTIME_MAX while we are handling the expired timers and
set it to the next expiry value after we handled the timers under the
base lock. While the expired timers are processed timer migration is
blocked because the expiry time of the timer is always -
The timer migration code needs to check whether the expiry time of the
timer is before the programmed clock event expiry time when the timer
is enqueued on another CPU because we can not reprogram the timer
device on the other CPU. The current logic checks the expiry time even
if we enqueue on the current CPU when nohz_get_load_balancer() returns
current CPU. This might lead to an endless loop in the expiry check
code when the expiry time of the timer is before the current
programmed next event.Check whether nohz_get_load_balancer() returns current CPU and skip
the expiry check if this is the case.The bug was triggered from the networking code. The patch fixes the
regression http://bugzilla.kernel.org/show_bug.cgi?id=13738
(Soft-Lockup/Race in networking in 2.6.31-rc1+195)Cc: Arun Bharadwaj
Tested-by: Andres Freund
Signed-off-by: Thomas Gleixner
18 Jun, 2009
1 commit
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* 'linux-next' of git://git.infradead.org/ubifs-2.6:
UBIFS: start using hrtimers
hrtimer: export ktime_add_safe
UBIFS: do not forget to register BDI device
UBIFS: allow sync option in rootflags
UBIFS: remove dead code
UBIFS: use anonymous device
UBIFS: return proper error code if the compr is not present
UBIFS: return error if link and unlink race
UBIFS: reset no_space flag after inode deletion
08 Jun, 2009
1 commit
-
We want to use hrtimers in UBIFS (for write-buffer write-back timer).
We need the 'hrtimer_set_expires_range_ns()', which is an in-line
function which uses 'ktime_add_safe()'.Signed-off-by: Artem Bityutskiy
Acked-by: Ingo Molnar
13 May, 2009
2 commits
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* Arun R Bharadwaj [2009-04-16 12:11:36]:
This patch migrates all non pinned timers and hrtimers to the current
idle load balancer, from all the idle CPUs. Timers firing on busy CPUs
are not migrated.While migrating hrtimers, care should be taken to check if migrating
a hrtimer would result in a latency or not. So we compare the expiry of the
hrtimer with the next timer interrupt on the target cpu and migrate the
hrtimer only if it expires *after* the next interrupt on the target cpu.
So, added a clockevents_get_next_event() helper function to return the
next_event on the target cpu's clock_event_device.[ tglx: cleanups and simplifications ]
Signed-off-by: Arun R Bharadwaj
Signed-off-by: Thomas Gleixner -
* Arun R Bharadwaj [2009-04-16 12:11:36]:
This patch creates a new framework for identifying cpu-pinned timers
and hrtimers.This framework is needed because pinned timers are expected to fire on
the same CPU on which they are queued. So it is essential to identify
these and not migrate them, in case there are any.For regular timers, the currently existing add_timer_on() can be used
queue pinned timers and subsequently mod_timer_pinned() can be used
to modify the 'expires' field.For hrtimers, new modes HRTIMER_ABS_PINNED and HRTIMER_REL_PINNED are
added to queue cpu-pinned hrtimer.[ tglx: use .._PINNED mode argument instead of creating tons of new
functions ]Signed-off-by: Arun R Bharadwaj
Signed-off-by: Thomas Gleixner
31 Mar, 2009
1 commit
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It appears I inadvertly introduced rq->lock recursion to the
hrtimer_start() path when I delegated running already expired
timers to softirq context.This patch fixes it by introducing a __hrtimer_start_range_ns()
method that will not use raise_softirq_irqoff() but
__raise_softirq_irqoff() which avoids the wakeup.It then also changes schedule() to check for pending softirqs and
do the wakeup then, I'm not quite sure I like this last bit, nor
am I convinced its really needed.Signed-off-by: Peter Zijlstra
Cc: Peter Zijlstra
Cc: paulus@samba.org
LKML-Reference:
Signed-off-by: Ingo Molnar
31 Jan, 2009
3 commits
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Impact: prevent false positive WARN_ON() in clockevents_program_event()
clock_was_set() changes the base->offset of CLOCK_REALTIME and
enforces the reprogramming of the clockevent device to expire timers
which are based on CLOCK_REALTIME. If the clock change is large enough
then the subtraction of the timer expiry value and base->offset can
become negative which triggers the warning in
clockevents_program_event().Check the subtraction result and set a negative value to 0.
Signed-off-by: Thomas Gleixner
-
Impact: fix CPU hotplug hang on Power6 testbox
On architectures that support offlining all cpus (at least powerpc/pseries),
hot-unpluging the tick_do_timer_cpu can result in a system hang.This comes from the fact that if the cpu going down happens to be the
cpu doing the tick, then as the tick_do_timer_cpu handover happens after the
cpu is dead (via the CPU_DEAD notification), we're left without ticks,
jiffies are frozen and any task relying on timers (msleep, ...) is stuck.
That's particularly the case for the cpu looping in __cpu_die() waiting
for the dying cpu to be dead.This patch addresses this by having the tick_do_timer_cpu handover happen
earlier during the CPU_DYING notification. For this, a new clockevent
notification type is introduced (CLOCK_EVT_NOTIFY_CPU_DYING) which is triggered
in hrtimer_cpu_notify().Signed-off-by: Sebastien Dugue
Cc:
Signed-off-by: Ingo Molnar -
Impact: avoid timer IRQ hanging slow systems
While using the function graph tracer on a virtualized system, the
hrtimer_interrupt can hang the system on an infinite loop.This can be caused in several situations:
- the hardware is very slow and HZ is set too high
- something intrusive is slowing the system down (tracing under emulation)
... and the next clock events to program are always before the current time.
This patch implements a reasonable compromise: if such a situation is
detected, we share the CPUs time in 1/4 to process the hrtimer interrupts.
This is enough to let the system running without serious starvation.It has been successfully tested under VirtualBox with 1000 HZ and 100 HZ
with function graph tracer launched. On both cases, the clock events were
increased until about 25 ms periodic ticks, which means 40 HZ.So we change a hard to debug hang into a warning message and a system that
still manages to limp along.Signed-off-by: Frederic Weisbecker
Signed-off-by: Ingo Molnar
27 Jan, 2009
1 commit
-
…el/git/tip/linux-2.6-tip
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
hrtimers: fix inconsistent lock state on resume in hres_timers_resume
time-sched.c: tick_nohz_update_jiffies should be static
locking, hpet: annotate false positive warning
kernel/fork.c: unused variable 'ret'
itimers: remove the per-cpu-ish-ness
19 Jan, 2009
1 commit
-
Andrey Borzenkov reported this lockdep assert:
> [17854.688347] =================================
> [17854.688347] [ INFO: inconsistent lock state ]
> [17854.688347] 2.6.29-rc2-1avb #1
> [17854.688347] ---------------------------------
> [17854.688347] inconsistent {in-hardirq-W} -> {hardirq-on-W} usage.
> [17854.688347] pm-suspend/18240 [HC0[0]:SC0[0]:HE1:SE1] takes:
> [17854.688347] (&cpu_base->lock){++..}, at: [] retrigger_next_event+0x5c/0xa0
> [17854.688347] {in-hardirq-W} state was registered at:
> [17854.688347] [] __lock_acquire+0x79d/0x1930
> [17854.688347] [] lock_acquire+0x5c/0x80
> [17854.688347] [] _spin_lock+0x35/0x70
> [17854.688347] [] hrtimer_run_queues+0x31/0x140
> [17854.688347] [] run_local_timers+0x8/0x20
> [17854.688347] [] update_process_times+0x23/0x60
> [17854.688347] [] tick_periodic+0x24/0x80
> [17854.688347] [] tick_handle_periodic+0x12/0x70
> [17854.688347] [] timer_interrupt+0x14/0x20
> [17854.688347] [] handle_IRQ_event+0x29/0x60
> [17854.688347] [] handle_level_irq+0x69/0xe0
> [17854.688347] [] 0xffffffff
> [17854.688347] irq event stamp: 55771
> [17854.688347] hardirqs last enabled at (55771): [] _spin_unlock_irqrestore+0x35/0x60
> [17854.688347] hardirqs last disabled at (55770): [] _spin_lock_irqsave+0x19/0x80
> [17854.688347] softirqs last enabled at (54836): [] __do_softirq+0xc4/0x110
> [17854.688347] softirqs last disabled at (54831): [] do_softirq+0x8e/0xe0
> [17854.688347]
> [17854.688347] other info that might help us debug this:
> [17854.688347] 3 locks held by pm-suspend/18240:
> [17854.688347] #0: (&buffer->mutex){--..}, at: [] sysfs_write_file+0x25/0x100
> [17854.688347] #1: (pm_mutex){--..}, at: [] enter_state+0x4f/0x140
> [17854.688347] #2: (dpm_list_mtx){--..}, at: [] device_pm_lock+0xf/0x20
> [17854.688347]
> [17854.688347] stack backtrace:
> [17854.688347] Pid: 18240, comm: pm-suspend Not tainted 2.6.29-rc2-1avb #1
> [17854.688347] Call Trace:
> [17854.688347] [] ? printk+0x18/0x20
> [17854.688347] [] print_usage_bug+0x16c/0x1d0
> [17854.688347] [] mark_lock+0x8bf/0xc90
> [17854.688347] [] ? pit_next_event+0x2f/0x40
> [17854.688347] [] __lock_acquire+0x580/0x1930
> [17854.688347] [] ? _spin_unlock+0x1d/0x20
> [17854.688347] [] ? pit_next_event+0x2f/0x40
> [17854.688347] [] ? clockevents_program_event+0x98/0x160
> [17854.688347] [] ? mark_held_locks+0x48/0x90
> [17854.688347] [] ? _spin_unlock_irqrestore+0x35/0x60
> [17854.688347] [] ? trace_hardirqs_on_caller+0x139/0x190
> [17854.688347] [] ? trace_hardirqs_on+0xb/0x10
> [17854.688347] [] lock_acquire+0x5c/0x80
> [17854.688347] [] ? retrigger_next_event+0x5c/0xa0
> [17854.688347] [] _spin_lock+0x35/0x70
> [17854.688347] [] ? retrigger_next_event+0x5c/0xa0
> [17854.688347] [] retrigger_next_event+0x5c/0xa0
> [17854.688347] [] hres_timers_resume+0xa/0x10
> [17854.688347] [] timekeeping_resume+0xee/0x150
> [17854.688347] [] __sysdev_resume+0x14/0x50
> [17854.688347] [] sysdev_resume+0x47/0x80
> [17854.688347] [] device_power_up+0xb/0x20
> [17854.688347] [] suspend_devices_and_enter+0xcf/0x150
> [17854.688347] [] ? freeze_processes+0x3f/0x90
> [17854.688347] [] enter_state+0xf4/0x140
> [17854.688347] [] state_store+0x7d/0xc0
> [17854.688347] [] ? state_store+0x0/0xc0
> [17854.688347] [] kobj_attr_store+0x24/0x30
> [17854.688347] [] sysfs_write_file+0x9c/0x100
> [17854.688347] [] vfs_write+0x9c/0x160
> [17854.688347] [] ? restore_nocheck_notrace+0x0/0xe
> [17854.688347] [] ? sysfs_write_file+0x0/0x100
> [17854.688347] [] sys_write+0x3d/0x70
> [17854.688347] [] sysenter_do_call+0x12/0x31Andrey's analysis:
> timekeeping_resume() is called via class ->resume
> method; and according to comments in sysdev_resume() and
> device_power_up(), they are called with interrupts disabled.
>
> Looking at suspend_enter, irqs *are* disabled at this point.
>
> So it actually looks like something (may be some driver)
> unconditionally enabled irqs in resume path.Add a debug check to test this theory. If it triggers then it
triggers because the resume code calls it with irqs enabled,
which is a no-no not just for timekeeping_resume(), but also
bad for a number of other resume handlers.Reported-by: Andrey Borzenkov
Signed-off-by: Peter Zijlstra
Signed-off-by: Ingo Molnar
14 Jan, 2009
1 commit
-
Signed-off-by: Heiko Carstens
05 Jan, 2009
6 commits
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Impact: build fix on !CONFIG_HIGH_RES_TIMERS
Fix:
kernel/hrtimer.c:1586: error: implicit declaration of function '__hrtimer_peek_ahead_timers'
Signen-off-by: Ingo Molnar
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Clean up the comments
Signed-off-by: Thomas Gleixner
Signed-off-by: Peter Zijlstra
Signed-off-by: Ingo Molnar -
Impact: fix rare runtime deadlock
There are a few sites that do:
spin_lock_irq(&foo)
hrtimer_start(&bar)
__run_hrtimer(&bar)
func()
spin_lock(&foo)which obviously deadlocks. In order to avoid this, never call __run_hrtimer()
from hrtimer_start*() context, but instead defer this to softirq context.Signed-off-by: Peter Zijlstra
Signed-off-by: Ingo Molnar -
Impact: cleanup
No need for a smp function call, which is likely to run on the same
CPU anyway. We can just call hrtimers_peek_ahead() in the interrupts
disabled section of migrate_hrtimers().Signed-off-by: Thomas Gleixner
Signed-off-by: Peter Zijlstra
Signed-off-by: Ingo Molnar -
Impact: cleanup
kernel/hrtimer.c: In function 'hrtimer_cpu_notify':
kernel/hrtimer.c:1574: warning: unused variable 'dcpu'Introduced by commit 37810659ea7d9572c5ac284ade272f806ef8f788
("hrtimer: removing all ur callback modes, fix hotplug") from the
timers. dcpu is only used if CONFIG_HOTPLUG_CPU is set.Reported-by: Stephen Rothwell
Signed-off-by: Thomas Gleixner
Signed-off-by: Peter Zijlstra
Signed-off-by: Ingo Molnar -
Impact: cleanup
Provide a peek ahead function that assumes irqs disabled, allows for micro
optimizations.Signed-off-by: Thomas Gleixner
Signed-off-by: Peter Zijlstra
Signed-off-by: Ingo Molnar
01 Jan, 2009
1 commit
-
…l/git/tip/linux-2.6-tip
* 'irq-fixes-for-linus-4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
sparseirq: move __weak symbols into separate compilation unit
sparseirq: work around __weak alias bug
sparseirq: fix hang with !SPARSE_IRQ
sparseirq: set lock_class for legacy irq when sparse_irq is selected
sparseirq: work around compiler optimizing away __weak functions
sparseirq: fix desc->lock init
sparseirq: do not printk when migrating IRQ descriptors
sparseirq: remove duplicated arch_early_irq_init()
irq: simplify for_each_irq_desc() usage
proc: remove ifdef CONFIG_SPARSE_IRQ from stat.c
irq: for_each_irq_desc() move to irqnr.h
hrtimer: remove #include <linux/irq.h>
26 Dec, 2008
1 commit
-
Impact: cleanup
can be removed and should be, because:
- hrtimer doesn't use any irq feature.
- shouldn't be include from generic code.Signed-off-by: KOSAKI Motohiro
Signed-off-by: Ingo Molnar
19 Dec, 2008
1 commit
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this warning:
kernel/hrtimer.c: In function ‘hrtimer_cpu_notify’:
kernel/hrtimer.c:1574: warning: unused variable ‘dcpu’is caused because 'dcpu' is only used in the CONFIG_HOTPLUG_CPU case.
Signed-off-by: Ingo Molnar
09 Dec, 2008
1 commit
-
> Ingo, this addition fixes the hotplug issue on my machine
And because we're all human...
Signed-off-by: Peter Zijlstra
Signed-off-by: Ingo Molnar
04 Dec, 2008
1 commit
-
Impact: fix hrtimer locking (reported by lockdep) in the CPU hotplug case
This addition fixes the hotplug locking issue on my machine
Signed-off-by: Peter Zijlstra
Signed-off-by: Ingo Molnar
25 Nov, 2008
1 commit
-
Impact: cleanup, move all hrtimer processing into hardirq context
This is an attempt at removing some of the hrtimer complexity by
reducing the number of callback modes to 1.This means that all hrtimer callback functions will be ran from HARD-irq
context.I went through all the 30 odd hrtimer callback functions in the kernel
and saw only one that I'm not quite sure of, which is the one in
net/can/bcm.c - hence I'm CC-ing the folks responsible for that code.Furthermore, the hrtimer core now calls callbacks directly with IRQs
disabled in case you try to enqueue an expired timer. If this timer is a
periodic timer (which should use hrtimer_forward() to advance its time)
then it might be possible to end up in an inf. recursive loop due to the
fact that hrtimer_forward() doesn't round up to the next timer
granularity, and therefore keeps on calling the callback - obviously
this needs a fix.Aside from that, this seems to compile and actually boot on my dual core
test box - although I'm sure there are some bugs in, me not hitting any
makes me certain :-)Signed-off-by: Peter Zijlstra
Signed-off-by: Ingo Molnar
12 Nov, 2008
1 commit
-
Impact: cleanup
git grep HRTIMER_CB_IRQSAFE revealed half the callback modes are actually
unused.Signed-off-by: Peter Zijlstra
Signed-off-by: Ingo Molnar
11 Nov, 2008
1 commit
-
Impact: fix incorrect locking triggered during hotplug-intense stress-tests
While migrating the the CB_IRQSAFE_UNLOCKED timers during a cpu-offline,
we queue them on the cb_pending list, so that they won't go
stale.Thus, when the callbacks of the timers run from the softirq context,
they could run into potential deadlocks, since these callbacks
assume that they're running with irq's disabled, thereby annoying
lockdep!Fix this by emulating hardirq context while running these callbacks from
the hrtimer softirq.=================================
[ INFO: inconsistent lock state ]
2.6.27 #2
--------------------------------
inconsistent {in-hardirq-W} -> {hardirq-on-W} usage.
ksoftirqd/0/4 [HC0[0]:SC1[1]:HE1:SE0] takes:
(&rq->lock){++..}, at: [] sched_rt_period_timer+0x9e/0x1fc
{in-hardirq-W} state was registered at:
[] __lock_acquire+0x549/0x121e
[] native_sched_clock+0x88/0x99
[] clocksource_get_next+0x39/0x3f
[] update_wall_time+0x616/0x7df
[] lock_acquire+0x5a/0x74
[] scheduler_tick+0x3a/0x18d
[] _spin_lock+0x1c/0x45
[] scheduler_tick+0x3a/0x18d
[] scheduler_tick+0x3a/0x18d
[] update_process_times+0x3a/0x44
[] tick_periodic+0x63/0x6d
[] tick_handle_periodic+0x14/0x5e
[] timer_interrupt+0x44/0x4a
[] handle_IRQ_event+0x13/0x3d
[] handle_level_irq+0x79/0xbd
[] do_IRQ+0x69/0x7d
[] common_interrupt+0x28/0x30
[] aac_probe_one+0x1a3/0x3f3
[] _spin_unlock_irqrestore+0x36/0x39
[] setup_irq+0x1be/0x1f9
[] start_kernel+0x259/0x2c5
[] 0xffffffff
irq event stamp: 50102
hardirqs last enabled at (50102): [] _spin_unlock_irq+0x20/0x23
hardirqs last disabled at (50101): [] _spin_lock_irq+0xa/0x4b
softirqs last enabled at (50088): [] do_softirq+0x37/0x4d
softirqs last disabled at (50099): [] do_softirq+0x37/0x4dother info that might help us debug this:
no locks held by ksoftirqd/0/4.stack backtrace:
Pid: 4, comm: ksoftirqd/0 Not tainted 2.6.27 #2
[] print_usage_bug+0x13e/0x147
[] mark_lock+0x493/0x797
[] __lock_acquire+0x5be/0x121e
[] lock_acquire+0x5a/0x74
[] sched_rt_period_timer+0x9e/0x1fc
[] _spin_lock+0x1c/0x45
[] sched_rt_period_timer+0x9e/0x1fc
[] sched_rt_period_timer+0x9e/0x1fc
[] finish_task_switch+0x41/0xbd
[] native_sched_clock+0x88/0x99
[] sched_rt_period_timer+0x0/0x1fc
[] run_hrtimer_pending+0x54/0xe5
[] sched_rt_period_timer+0x0/0x1fc
[] __do_softirq+0x7b/0xef
[] do_softirq+0x37/0x4d
[] ksoftirqd+0x56/0xc5
[] ksoftirqd+0x0/0xc5
[] kthread+0x38/0x5d
[] kthread+0x0/0x5d
[] kernel_thread_helper+0x7/0x10
=======================Signed-off-by: Gautham R Shenoy
Acked-by: Peter Zijlstra
Acked-by: "Paul E. McKenney"
Signed-off-by: Ingo Molnar
22 Oct, 2008
1 commit
-
Conflicts:
kernel/time/tick-sched.c
Signed-off-by: Thomas Gleixner
20 Oct, 2008
3 commits
-
Signed-off-by: Thomas Gleixner
-
hrtimer_start() and hrtimer_start_range_ns() handle relative and
absolute timers.Signed-off-by: Thomas Gleixner
-
…tp', 'timers/posixtimers' and 'timers/debug' into v28-timers-for-linus
18 Oct, 2008
1 commit
-
Conflicts:
arch/x86/kvm/i8254.c
13 Oct, 2008
1 commit
-
and please hand me a brown paper bag
(thanks to Thomas for pointing out this very obvious bug)
Signed-off-by: Arjan van de Ven
12 Oct, 2008
1 commit
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There's a small race/chance that, while hrtimers are enabled globally,
they're later not enabled when we're calling the hrtimer_interrupt() function,
which then BUG_ON()'s for that. This patch closes that race/gap.Signed-off-by: Arjan van de Ven
29 Sep, 2008
4 commits
-
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: Thomas Gleixner
-
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: Thomas Gleixner
-
Impact: Stale timers after a CPU went offline.
commit 37bb6cb4097e29ffee970065b74499cbf10603a3
hrtimer: unlock hrtimer_wakeupchanged 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: Thomas Gleixner
-
Impact: hrtimers which are on the pending list are not migrated at cpu
offline and can be stale foreverAdd the pending list migration when CONFIG_HIGH_RES_TIMERS is enabled
Signed-off-by: Thomas Gleixner
22 Sep, 2008
1 commit
-
Peter Zijlstra noticed this 8 months ago and I just noticed
it again.hrtimer_clock_base::get_softirq_time() is currently unused
in the entire tree. In fact, looking at the logs, it appears
as if it was never used. Remove it.Signed-off-by: Mark McLoughlin
Signed-off-by: Ingo Molnar
11 Sep, 2008
1 commit
-
As part of going idle, we already look at the time of the next timer event to determine
which C-state to select etc.This patch adds functionality that causes the timers that are past their
soft expire time, to fire at this time, before we calculate the next wakeup
time. This functionality will thus avoid wakeups by running timers before
going idle rather than specially waking up for it.Signed-off-by: Arjan van de Ven