Skip to content

R
raspberrypi-kernel

openeuler / raspberrypi-kernel

通知 13
Star 1
Fork 0
R
raspberrypi-kernel
切换分支/标签
  1. 16 4月, 2014 1 次提交
  3. 26 3月, 2014 2 次提交
  5. 24 12月, 2013 1 次提交
    • J
      tick/timekeeping: Call update_wall_time outside the jiffies lock · 47a1b796
      由 John Stultz 提交于 
      Since the xtime lock was split into the timekeeping lock and
the jiffies lock, we no longer need to call update_wall_time()
while holding the jiffies lock.

Thus, this patch splits update_wall_time() out from do_timer().

This allows us to get away from calling clock_was_set_delayed()
in update_wall_time() and instead use the standard clock_was_set()
call that previously would deadlock, as it causes the jiffies lock
to be acquired.

Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
      47a1b796
  7. 19 11月, 2013 1 次提交
  9. 02 7月, 2013 1 次提交
    • T
      tick: Sanitize broadcast control logic · 07bd1172
      由 Thomas Gleixner 提交于 
      The recent implementation of a generic dummy timer resulted in a
different registration order of per cpu local timers which made the
broadcast control logic go belly up.

If the dummy timer is the first clock event device which is registered
for a CPU, then it is installed, the broadcast timer is initialized
and the CPU is marked as broadcast target.

If a real clock event device is installed after that, we can fail to
take the CPU out of the broadcast mask. In the worst case we end up
with two periodic timer events firing for the same CPU. One from the
per cpu hardware device and one from the broadcast.

Now the problem is that we have no way to distinguish whether the
system is in a state which makes broadcasting necessary or the
broadcast bit was set due to the nonfunctional dummy timer
installment.

To solve this we need to keep track of the system state seperately and
provide a more detailed decision logic whether we keep the CPU in
broadcast mode or not.

The old decision logic only clears the broadcast mode, if the newly
installed clock event device is not affected by power states.

The new logic clears the broadcast mode if one of the following is
true:

  - The new device is not affected by power states.

  - The system is not in a power state affected mode

  - The system has switched to oneshot mode. The oneshot broadcast is
    controlled from the deep idle state. The CPU is not in idle at
    this point, so it's safe to remove it from the mask.

If we clear the broadcast bit for the CPU when a new device is
installed, we also shutdown the broadcast device when this was the
last CPU in the broadcast mask.

If the broadcast bit is kept, then we leave the new device in shutdown
state and rely on the broadcast to deliver the timer interrupts via
the broadcast ipis.
Reported-and-tested-by: NStehle Vincent-B46079 <B46079@freescale.com>
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Cc: John Stultz <john.stultz@linaro.org>,
Cc: Mark Rutland <mark.rutland@arm.com>
Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1307012153060.4013@ionos.tec.linutronix.de
Cc: stable@vger.kernel.org
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      07bd1172
  11. 25 6月, 2013 1 次提交
    • S
      clockevents: Prefer CPU local devices over global devices · 70e5975d
      由 Stephen Boyd 提交于 
      On an SMP system with only one global clockevent and a dummy
clockevent per CPU we run into problems. We want the dummy
clockevents to be registered as the per CPU tick devices, but
we can only achieve that if we register the dummy clockevents
before the global clockevent or if we artificially inflate the
rating of the dummy clockevents to be higher than the rating
of the global clockevent. Failure to do so leads to boot
hangs when the dummy timers are registered on all other CPUs
besides the CPU that accepted the global clockevent as its tick
device and there is no broadcast timer to poke the dummy
devices.

If we're registering multiple clockevents and one clockevent is
global and the other is local to a particular CPU we should
choose to use the local clockevent regardless of the rating of
the device. This way, if the clockevent is a dummy it will take
the tick device duty as long as there isn't a higher rated tick
device and any global clockevent will be bumped out into
broadcast mode, fixing the problem described above.
Reported-and-tested-by: NMark Rutland <mark.rutland@arm.com>
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Tested-by: soren.brinkmann@xilinx.com
Cc: John Stultz <john.stultz@linaro.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20130613183950.GA32061@codeaurora.orgSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
      70e5975d
  13. 16 5月, 2013 6 次提交
  15. 25 4月, 2013 1 次提交
    • T
      clockevents: Set dummy handler on CPU_DEAD shutdown · 6f7a05d7
      由 Thomas Gleixner 提交于 
      Vitaliy reported that a per cpu HPET timer interrupt crashes the
system during hibernation. What happens is that the per cpu HPET timer
gets shut down when the nonboot cpus are stopped. When the nonboot
cpus are onlined again the HPET code sets up the MSI interrupt which
fires before the clock event device is registered. The event handler
is still set to hrtimer_interrupt, which then crashes the machine due
to highres mode not being active.

See http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=700333

There is no real good way to avoid that in the HPET code. The HPET
code alrady has a mechanism to detect spurious interrupts when event
handler == NULL for a similar reason.

We can handle that in the clockevent/tick layer and replace the
previous functional handler with a dummy handler like we do in
tick_setup_new_device().

The original clockevents code did this in clockevents_exchange_device(),
but that got removed by commit 7c1e7689 (clockevents: prevent
clockevent event_handler ending up handler_noop) which forgot to fix
it up in tick_shutdown(). Same issue with the broadcast device.
Reported-by: NVitaliy Fillipov <vitalif@yourcmc.ru>
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: stable@vger.kernel.org
Cc: 700333@bugs.debian.org
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      6f7a05d7
  17. 16 4月, 2013 1 次提交
    • F
      nohz: Switch from "extended nohz" to "full nohz" based naming · c5bfece2
      由 Frederic Weisbecker 提交于 
      "Extended nohz" was used as a naming base for the full dynticks
API and Kconfig symbols. It reflects the fact the system tries
to stop the tick in more places than just idle.

But that "extended" name is a bit opaque and vague. Rename it to
"full" makes it clearer what the system tries to do under this
config: try to shutdown the tick anytime it can. The various
constraints that prevent that to happen shouldn't be considered
as fundamental properties of this feature but rather technical
issues that may be solved in the future.
Reported-by: NIngo Molnar <mingo@kernel.org>
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Gilad Ben Yossef <gilad@benyossef.com>
Cc: Hakan Akkan <hakanakkan@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Kevin Hilman <khilman@linaro.org>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
      c5bfece2
  19. 21 3月, 2013 1 次提交
    • F
      nohz: Assign timekeeping duty to a CPU outside the full dynticks range · a382bf93
      由 Frederic Weisbecker 提交于 
      This way the full nohz CPUs can safely run with the tick
stopped with a guarantee that somebody else is taking
care of the jiffies and GTOD progression.

Once the duty is attributed to a CPU, it won't change. Also that
CPU can't enter into dyntick idle mode or be hot unplugged.

This may later be improved from a power consumption POV. At
least we should be able to share the duty amongst all CPUs
outside the full dynticks range. Then the duty could even be
shared with full dynticks CPUs when those can't stop their
tick for any reason.

But let's start with that very simple approach first.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Gilad Ben Yossef <gilad@benyossef.com>
Cc: Hakan Akkan <hakanakkan@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Kevin Hilman <khilman@linaro.org>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
[fix have_nohz_full_mask offcase]
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
      a382bf93
  21. 07 3月, 2013 1 次提交
  23. 14 11月, 2012 1 次提交
  25. 08 9月, 2011 1 次提交
  27. 26 2月, 2011 1 次提交
    • T
      clockevents: Prevent oneshot mode when broadcast device is periodic · 3a142a06
      由 Thomas Gleixner 提交于 
      When the per cpu timer is marked CLOCK_EVT_FEAT_C3STOP, then we only
can switch into oneshot mode, when the backup broadcast device
supports oneshot mode as well. Otherwise we would try to switch the
broadcast device into an unsupported mode unconditionally. This went
unnoticed so far as the current available broadcast devices support
oneshot mode. Seth unearthed this problem while debugging and working
around an hpet related BIOS wreckage.

Add the necessary check to tick_is_oneshot_available().
Reported-and-tested-by: NSeth Forshee <seth.forshee@canonical.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
LKML-Reference: <alpine.LFD.2.00.1102252231200.2701@localhost6.localdomain6>
Cc: stable@kernel.org # .21 ->
      3a142a06
  29. 01 2月, 2011 1 次提交
  31. 17 12月, 2010 1 次提交
  33. 15 12月, 2009 2 次提交
  35. 02 5月, 2009 1 次提交
    • J
      clockevents: prevent endless loop in tick_handle_periodic() · 74a03b69
      由 john stultz 提交于 
      tick_handle_periodic() can lock up hard when a one shot clock event
device is used in combination with jiffies clocksource.

Avoid an endless loop issue by requiring that a highres valid
clocksource be installed before we call tick_periodic() in a loop when
using ONESHOT mode. The result is we will only increment jiffies once
per interrupt until a continuous hardware clocksource is available.

Without this, we can run into a endless loop, where each cycle through
the loop, jiffies is updated which increments time by tick_period or
more (due to clock steering), which can cause the event programming to
think the next event was before the newly incremented time and fail
causing tick_periodic() to be called again and the whole process loops
forever.

[ Impact: prevent hard lock up ]
Signed-off-by: NJohn Stultz <johnstul@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: stable@kernel.org
      74a03b69
  37. 31 1月, 2009 1 次提交
    • S
      hrtimers: allow the hot-unplugging of all cpus · 94df7de0
      由 Sebastien Dugue 提交于 
      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: NSebastien Dugue <sebastien.dugue@bull.net>
Cc: <stable@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      94df7de0
  39. 01 1月, 2009 1 次提交
    • R
      cpumask: convert kernel time functions · 6b954823
      由 Rusty Russell 提交于 
      Impact: Use new APIs

Convert kernel/time functions to use struct cpumask *.

Note the ugly bitmap declarations in tick-broadcast.c.  These should
be cpumask_var_t, but there was no obvious initialization function to
put the alloc_cpumask_var() calls in.  This was safe.

(Eventually 'struct cpumask' will be undefined for CONFIG_CPUMASK_OFFSTACK,
so we use a bitmap here to show we really mean it).
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NMike Travis <travis@sgi.com>
      6b954823
  41. 30 12月, 2008 1 次提交
    • S
      hrtimers: allow the hot-unplugging of all cpus · 5762ba18
      由 Sebastien Dugue 提交于 
      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: NSebastien Dugue <sebastien.dugue@bull.net>
Cc: <stable@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      5762ba18
  43. 13 12月, 2008 2 次提交
  45. 23 9月, 2008 2 次提交
    • T
      clockevents: prevent mode mismatch on cpu online · 27ce4cb4
      由 Thomas Gleixner 提交于 
      Impact: timer hang on CPU online observed on AMD C1E systems

When a CPU is brought online then the broadcast machinery can
be in the one shot state already. Check this and setup the timer 
device of the new CPU in one shot mode so the broadcast code
can pick up the next_event value correctly.

Another AMD C1E oddity, as we switch to broadcast immediately and
not after the full bring up via the ACPI cpu idle code.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      27ce4cb4
    • T
      clockevents: prevent cpu online to interfere with nohz · 6441402b
      由 Thomas Gleixner 提交于 
      Impact: rare hang which can be triggered on CPU online.

tick_do_timer_cpu keeps track of the CPU which updates jiffies
via do_timer. The value -1 is used to signal, that currently no
CPU is doing this. There are two cases, where the variable can 
have this state:

 boot:
    necessary for systems where the boot cpu id can be != 0

 nohz long idle sleep:
    When the CPU which did the jiffies update last goes into
    a long idle sleep it drops the update jiffies duty so
    another CPU which is not idle can pick it up and keep
    jiffies going.

Using the same value for both situations is wrong, as the CPU online
code can see the -1 state when the timer of the newly onlined CPU is
setup. The setup for a newly onlined CPU goes through periodic mode
and can pick up the do_timer duty without being aware of the nohz /
highres mode of the already running system.

Use two separate states and make them constants to avoid magic
numbers confusion. 
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      6441402b
  47. 17 9月, 2008 1 次提交
    • T
      clockevents: make device shutdown robust · 2344abbc
      由 Thomas Gleixner 提交于 
      The device shut down does not cleanup the next_event variable of the
clock event device. So when the device is reactivated the possible
stale next_event value can prevent the device to be reprogrammed as it
claims to wait on a event already.

This is the root cause of the resurfacing suspend/resume problem,
where systems need key press to come back to life.

Fix this by setting next_event to KTIME_MAX when the device is shut
down. Use a separate function for shutdown which takes care of that
and only keep the direct set mode call in the broadcast code, where we
can not touch the next_event value.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      2344abbc
  49. 05 9月, 2008 1 次提交
    • V
      clockevents: prevent clockevent event_handler ending up handler_noop · 7c1e7689
      由 Venkatesh Pallipadi 提交于 
      There is a ordering related problem with clockevents code, due to which
clockevents_register_device() called after tickless/highres switch
will not work. The new clockevent ends up with clockevents_handle_noop as
event handler, resulting in no timer activity.

The problematic path seems to be

* old device already has hrtimer_interrupt as the event_handler
* new clockevent device registers with a higher rating
* tick_check_new_device() is called
  * clockevents_exchange_device() gets called
    * old->event_handler is set to clockevents_handle_noop
  * tick_setup_device() is called for the new device
    * which sets new->event_handler using the old->event_handler which is noop.

Change the ordering so that new device inherits the proper handler.

This does not have any issue in normal case as most likely all the clockevent
devices are setup before the highres switch. But, can potentially be affecting
some corner case where HPET force detect happens after the highres switch.
This was a problem with HPET in MSI mode code that we have been experimenting
with.
Signed-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NShaohua Li <shaohua.li@intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      7c1e7689
  51. 26 7月, 2008 1 次提交
  53. 19 7月, 2008 1 次提交
  55. 17 4月, 2008 1 次提交
    • R
      [S390] genirq/clockevents: move irq affinity prototypes/inlines to interrupt.h · d7b90689
      由 Russell King 提交于 
      > Generic code is not supposed to include irq.h. Replace this include
> by linux/hardirq.h instead and add/replace an include of linux/irq.h
> in asm header files where necessary.
> This change should only matter for architectures that make use of
> GENERIC_CLOCKEVENTS.
> Architectures in question are mips, x86, arm, sh, powerpc, uml and sparc64.
>
> I did some cross compile tests for mips, x86_64, arm, powerpc and sparc64.
> This patch fixes also build breakages caused by the include replacement in
> tick-common.h.

I generally dislike adding optional linux/* includes in asm/* includes -
I'm nervous about this causing include loops.

However, there's a separate point to be discussed here.

That is, what interfaces are expected of every architecture in the kernel.
If generic code wants to be able to set the affinity of interrupts, then
that needs to become part of the interfaces listed in linux/interrupt.h
rather than linux/irq.h.

So what I suggest is this approach instead (against Linus' tree of a
couple of days ago) - we move irq_set_affinity() and irq_can_set_affinity()
to linux/interrupt.h, change the linux/irq.h includes to linux/interrupt.h
and include asm/irq_regs.h where needed (asm/irq_regs.h is supposed to be
rarely used include since not much touches the stacked parent context
registers.)

Build tested on ARM PXA family kernels and ARM's Realview platform
kernels which both use genirq.

[ tglx@linutronix.de: add GENERIC_HARDIRQ dependencies ]
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
      d7b90689
  57. 15 10月, 2007 1 次提交
    • T
      clockevents: introduce force broadcast notifier · 1595f452
      由 Thomas Gleixner 提交于 
      The 64bit SMP bootup is slightly different to the 32bit one. It enables
the boot CPU local APIC timer before all CPUs are brought up. Some AMD C1E
systems have the C1E feature flag only set in the secondary CPU. Due to
the early enable of the boot CPU local APIC timer the APIC timer is
registered as a fully functional device. When we detect the wreckage during
the bringup of the secondary CPU, we need to force the boot CPU into
broadcast mode. 

Add a new notifier reason and implement the force broadcast in the clock
events layer.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      1595f452
  59. 13 10月, 2007 1 次提交
  61. 22 7月, 2007 1 次提交