linux.git/kernel/time/tick-oneshot.c, branch v5.10.258

hrtimers/tick/clockevents: Remove sloppy license references

2018-11-23T10:51:21+00:00

"For licencing details see kernel-base/COPYING" and similar license
references have no value over the SPDX identifier. Remove them.

Signed-off-by: Thomas Gleixner 
Acked-by: Kees Cook 
Acked-by: Ingo Molnar 
Acked-by: John Stultz 
Acked-by: Corey Minyard 
Cc: Peter Zijlstra 
Cc: Kate Stewart 
Cc: Philippe Ombredanne 
Cc: Peter Anvin 
Cc: Russell King 
Cc: Richard Cochran 
Cc: "Paul E. McKenney" 
Cc: Nicolas Pitre 
Cc: David Riley 
Cc: Colin Cross 
Cc: Mark Brown 
Link: https://lkml.kernel.org/r/20181031182252.963632760@linutronix.de

time: Add SPDX license identifiers

2018-11-23T10:51:20+00:00

Update the time(r) core files files with the correct SPDX license
identifier based on the license text in the file itself. The SPDX
identifier is a legally binding shorthand, which can be used instead of the
full boiler plate text.

This work is based on a script and data from Philippe Ombredanne, Kate
Stewart and myself. The data has been created with two independent license
scanners and manual inspection.

The following files do not contain any direct license information and have
been omitted from the big initial SPDX changes:

  timeconst.bc: The .bc files were not touched
  time.c, timer.c, timekeeping.c: Licence was deduced from EXPORT_SYMBOL_GPL

As those files do not contain direct license references they fall under the
project license, i.e. GPL V2 only.

Signed-off-by: Thomas Gleixner 
Acked-by: Kees Cook 
Acked-by: Ingo Molnar 
Acked-by: John Stultz 
Acked-by: Corey Minyard 
Cc: Peter Zijlstra 
Cc: Kate Stewart 
Cc: Philippe Ombredanne 
Cc: Russell King 
Cc: Richard Cochran 
Cc: Nicolas Pitre 
Cc: David Riley 
Cc: Colin Cross 
Cc: Mark Brown 
Cc: H. Peter Anvin 
Cc: Paul E. McKenney 
Link: https://lkml.kernel.org/r/20181031182252.879109557@linutronix.de

time: Remove useless filenames in top level comments

2018-11-23T10:51:20+00:00

Remove the pointless filenames in the top level comments. They have no
value at all and just occupy space. While at it tidy up some of the
comments and remove a stale one.

Signed-off-by: Thomas Gleixner 
Acked-by: Nicolas Pitre 
Acked-by: Kees Cook 
Acked-by: Ingo Molnar 
Acked-by: John Stultz 
Acked-by: Corey Minyard 
Cc: Peter Zijlstra 
Cc: Kate Stewart 
Cc: Philippe Ombredanne 
Cc: Peter Anvin 
Cc: Russell King 
Cc: Richard Cochran 
Cc: "Paul E. McKenney" 
Cc: David Riley 
Cc: Colin Cross 
Cc: Mark Brown 
Link: https://lkml.kernel.org/r/20181031182252.794898238@linutronix.de

clockevents: Fix kernel messages split across multiple lines

2018-04-17T15:18:04+00:00

Convert the clockevents driver from old-style printk() to pr_info() and
pr_cont(), to fix split kernel messages like below:

    Clockevents: could not switch to one-shot mode:
     dummy_timer is not functional.

Signed-off-by: Geert Uytterhoeven 
Signed-off-by: Thomas Gleixner 
Cc: Frederic Weisbecker 
Link: https://lkml.kernel.org/r/1522942018-14471-1-git-send-email-geert%2Brenesas@glider.be

clockevents: Update clockevents device next_event on stop

2017-11-01T17:20:17+00:00

clockevent_device::next_event holds the next timer event of a clock event
device. The value is updated in clockevents_program_event(), i.e. when the
hardware timer is armed for the next expiry.

When there are no software timers armed on a CPU, the corresponding per CPU
clockevent device is brought into ONESHOT_STOPPED state, but
clockevent_device::next_event is not updated, because
clockevents_program_event() is not called.

So the content of clockevent_device::next_event is stale, which is not an
issue when real hardware is used. But the hrtimer broadcast device relies
on that information and the stale value causes spurious wakeups.

Update clockevent_device::next_event to KTIME_MAX when it has been brought
into ONESHOT_STOPPED state to avoid spurious wakeups. This reflects the
proper expiry time of the stopped timer: infinity.

[ tglx: Massaged changelog ]

Signed-off-by: Prasad Sodagudi 
Signed-off-by: Thomas Gleixner 
Cc: viresh.kumar@linaro.org
Link: https://lkml.kernel.org/r/1509043042-32486-1-git-send-email-psodagud@codeaurora.org

ktime: Get rid of the union

2016-12-25T16:21:22+00:00

ktime is a union because the initial implementation stored the time in
scalar nanoseconds on 64 bit machine and in a endianess optimized timespec
variant for 32bit machines. The Y2038 cleanup removed the timespec variant
and switched everything to scalar nanoseconds. The union remained, but
become completely pointless.

Get rid of the union and just keep ktime_t as simple typedef of type s64.

The conversion was done with coccinelle and some manual mopping up.

Signed-off-by: Thomas Gleixner 
Cc: Peter Zijlstra

clockevents: Provide functions to set and get the state

2015-06-02T12:40:47+00:00

We want to rename dev->state, so provide proper get and set
functions. Rename clockevents_set_state() to
clockevents_switch_state() to avoid confusion.

Signed-off-by: Thomas Gleixner 
Cc: Viresh Kumar 
Cc: Peter Zijlstra

clockevents: Use helpers to check the state of a clockevent device

2015-06-02T12:40:47+00:00

Use accessor functions to check the state of clockevent devices in
core code.

Signed-off-by: Viresh Kumar 
Cc: linaro-kernel@lists.linaro.org
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/fa2b9869fd17f210eaa156ec2b594efd0230b6c7.1432192527.git.viresh.kumar@linaro.org
Signed-off-by: Thomas Gleixner

clockevents: Stop unused clockevent devices

2015-05-19T14:18:11+00:00

To avoid getting spurious interrupts on a tickless CPU, clockevent
device can now be stopped by switching to ONESHOT_STOPPED state.

The natural place for handling this transition is tick_program_event().

On 'expires == KTIME_MAX', we skip programming the event and so we need
to fix such call sites as well, to always call tick_program_event()
irrespective of the expires value.

Once the clockevent device is required again, check if it was earlier
put into ONESHOT_STOPPED state. If yes, switch its state to ONESHOT
before programming its event.

To make sure we haven't missed any corner case, add a WARN() for the
case where we try to reprogram clockevent device while we aren't
configured in ONESHOT_STOPPED state.

Signed-off-by: Viresh Kumar 
Cc: linaro-kernel@lists.linaro.org
Cc: Frederic Weisbecker 
Cc: Kevin Hilman 
Cc: Daniel Lezcano 
Cc: Preeti U Murthy 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/5146b07be7f0bc497e0ebae036590ec2fa73e540.1428031396.git.viresh.kumar@linaro.org
Signed-off-by: Thomas Gleixner

clockevents: Manage device's state separately for the core

2015-03-27T09:26:19+00:00

'enum clock_event_mode' is used for two purposes today:

 - to pass mode to the driver of clockevent device::set_mode().

 - for managing state of the device for clockevents core.

For supporting new modes/states we have moved away from the
legacy set_mode() callback to new per-mode/state callbacks. New
modes/states shouldn't be exposed to the legacy (now OBSOLOTE)
callbacks and so we shouldn't add new states to 'enum
clock_event_mode'.

Lets have separate enums for the two use cases mentioned above.
Keep using the earlier enum for legacy set_mode() callback and
mark it OBSOLETE. And add another enum to clearly specify the
possible states of a clockevent device.

This also renames the newly added per-mode callbacks to reflect
state changes.

We haven't got rid of 'mode' member of 'struct
clock_event_device' as it is used by some of the clockevent
drivers and it would automatically die down once we migrate
those drivers to the new interface. It ('mode') is only updated
now for the drivers using the legacy interface.

Suggested-by: Peter Zijlstra 
Suggested-by: Ingo Molnar 
Signed-off-by: Viresh Kumar 
Acked-by: Peter Zijlstra 
Cc: Daniel Lezcano 
Cc: Frederic Weisbecker 
Cc: Kevin Hilman 
Cc: Preeti U Murthy 
Cc: linaro-kernel@lists.linaro.org
Cc: linaro-networking@linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/b6b0143a8a57bd58352ad35e08c25424c879c0cb.1425037853.git.viresh.kumar@linaro.org
Signed-off-by: Ingo Molnar