linux-toradex.git/include/linux/hrtimer.h, branch v5.0-rc3

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

Revert: Unify CLOCK_MONOTONIC and CLOCK_BOOTTIME

2018-04-26T12:53:32+00:00

Revert commits

92af4dcb4e1c ("tracing: Unify the "boot" and "mono" tracing clocks")
127bfa5f4342 ("hrtimer: Unify MONOTONIC and BOOTTIME clock behavior")
7250a4047aa6 ("posix-timers: Unify MONOTONIC and BOOTTIME clock behavior")
d6c7270e913d ("timekeeping: Remove boot time specific code")
f2d6fdbfd238 ("Input: Evdev - unify MONOTONIC and BOOTTIME clock behavior")
d6ed449afdb3 ("timekeeping: Make the MONOTONIC clock behave like the BOOTTIME clock")
72199320d49d ("timekeeping: Add the new CLOCK_MONOTONIC_ACTIVE clock")

As stated in the pull request for the unification of CLOCK_MONOTONIC and
CLOCK_BOOTTIME, it was clear that we might have to revert the change.

As reported by several folks systemd and other applications rely on the
documented behaviour of CLOCK_MONOTONIC on Linux and break with the above
changes. After resume daemons time out and other timeout related issues are
observed. Rafael compiled this list:

* systemd kills daemons on resume, after >WatchdogSec seconds
  of suspending (Genki Sky).  [Verified that that's because systemd uses
  CLOCK_MONOTONIC and expects it to not include the suspend time.]

* systemd-journald misbehaves after resume:
  systemd-journald[7266]: File /var/log/journal/016627c3c4784cd4812d4b7e96a34226/system.journal
corrupted or uncleanly shut down, renaming and replacing.
  (Mike Galbraith).

* NetworkManager reports "networking disabled" and networking is broken
  after resume 50% of the time (Pavel).  [May be because of systemd.]

* MATE desktop dims the display and starts the screensaver right after
  system resume (Pavel).

* Full system hang during resume (me).  [May be due to systemd or NM or both.]

That happens on debian and open suse systems.

It's sad, that these problems were neither catched in -next nor by those
folks who expressed interest in this change.

Reported-by: Rafael J. Wysocki 
Reported-by: Genki Sky ,
Reported-by: Pavel Machek 
Signed-off-by: Thomas Gleixner 
Cc: Dmitry Torokhov 
Cc: John Stultz 
Cc: Jonathan Corbet 
Cc: Kevin Easton 
Cc: Linus Torvalds 
Cc: Mark Salyzyn 
Cc: Michael Kerrisk 
Cc: Peter Zijlstra 
Cc: Petr Mladek 
Cc: Prarit Bhargava 
Cc: Sergey Senozhatsky 
Cc: Steven Rostedt

Merge branches 'pm-cpuidle' and 'pm-qos'

2018-04-11T11:22:46+00:00

* pm-cpuidle:
  tick-sched: avoid a maybe-uninitialized warning
  cpuidle: Add definition of residency to sysfs documentation
  time: hrtimer: Use timerqueue_iterate_next() to get to the next timer
  nohz: Avoid duplication of code related to got_idle_tick
  nohz: Gather tick_sched booleans under a common flag field
  cpuidle: menu: Avoid selecting shallow states with stopped tick
  cpuidle: menu: Refine idle state selection for running tick
  sched: idle: Select idle state before stopping the tick
  time: hrtimer: Introduce hrtimer_next_event_without()
  time: tick-sched: Split tick_nohz_stop_sched_tick()
  cpuidle: Return nohz hint from cpuidle_select()
  jiffies: Introduce USER_TICK_USEC and redefine TICK_USEC
  sched: idle: Do not stop the tick before cpuidle_idle_call()
  sched: idle: Do not stop the tick upfront in the idle loop
  time: tick-sched: Reorganize idle tick management code

* pm-qos:
  PM / QoS: mark expected switch fall-throughs

time: hrtimer: Introduce hrtimer_next_event_without()

2018-04-07T16:49:54+00:00

The next set of changes will need to compute the time to the next
hrtimer event over all hrtimers except for the scheduler tick one.

To that end introduce a new helper function,
hrtimer_next_event_without(), for computing the time until the next
hrtimer event over all timers except for one and modify the underlying
code in __hrtimer_next_event_base() to prepare it for being called by
that new function.

No intentional changes in functionality.

Signed-off-by: Rafael J. Wysocki 
Acked-by: Peter Zijlstra (Intel) 
Reviewed-by: Frederic Weisbecker

hrtimer: Unify MONOTONIC and BOOTTIME clock behavior

2018-03-13T06:34:23+00:00

Now that th MONOTONIC and BOOTTIME clocks are indentical remove all the special
casing.

The user space visible interfaces still support both clocks, but their behavior
is identical.

Signed-off-by: Thomas Gleixner 
Cc: Dmitry Torokhov 
Cc: John Stultz 
Cc: Jonathan Corbet 
Cc: Kevin Easton 
Cc: Linus Torvalds 
Cc: Mark Salyzyn 
Cc: Michael Kerrisk 
Cc: Peter Zijlstra 
Cc: Petr Mladek 
Cc: Prarit Bhargava 
Cc: Sergey Senozhatsky 
Cc: Steven Rostedt 
Link: http://lkml.kernel.org/r/20180301165150.410218515@linutronix.de
Signed-off-by: Ingo Molnar

hrtimer: Implement support for softirq based hrtimers

2018-01-16T08:51:22+00:00

hrtimer callbacks are always invoked in hard interrupt context. Several
users in tree require soft interrupt context for their callbacks and
achieve this by combining a hrtimer with a tasklet. The hrtimer schedules
the tasklet in hard interrupt context and the tasklet callback gets invoked
in softirq context later.

That's suboptimal and aside of that the real-time patch moves most of the
hrtimers into softirq context. So adding native support for hrtimers
expiring in softirq context is a valuable extension for both mainline and
the RT patch set.

Each valid hrtimer clock id has two associated hrtimer clock bases: one for
timers expiring in hardirq context and one for timers expiring in softirq
context.

Implement the functionality to associate a hrtimer with the hard or softirq
related clock bases and update the relevant functions to take them into
account when the next expiry time needs to be evaluated.

Add a check into the hard interrupt context handler functions to check
whether the first expiring softirq based timer has expired. If it's expired
the softirq is raised and the accounting of softirq based timers to
evaluate the next expiry time for programming the timer hardware is skipped
until the softirq processing has finished. At the end of the softirq
processing the regular processing is resumed.

Suggested-by: Thomas Gleixner 
Suggested-by: Peter Zijlstra 
Signed-off-by: Anna-Maria Gleixner 
Cc: Christoph Hellwig 
Cc: John Stultz 
Cc: Linus Torvalds 
Cc: keescook@chromium.org
Link: http://lkml.kernel.org/r/20171221104205.7269-29-anna-maria@linutronix.de
Signed-off-by: Ingo Molnar

hrtimer: Add clock bases and hrtimer mode for softirq context

2018-01-16T02:00:50+00:00

Currently hrtimer callback functions are always executed in hard interrupt
context. Users of hrtimers, which need their timer function to be executed
in soft interrupt context, make use of tasklets to get the proper context.

Add additional hrtimer clock bases for timers which must expire in softirq
context, so the detour via the tasklet can be avoided. This is also
required for RT, where the majority of hrtimer is moved into softirq
hrtimer context.

The selection of the expiry mode happens via a mode bit. Introduce
HRTIMER_MODE_SOFT and the matching combinations with the ABS/REL/PINNED
bits and update the decoding of hrtimer_mode in tracepoints.

Signed-off-by: Anna-Maria Gleixner 
Cc: Christoph Hellwig 
Cc: John Stultz 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: keescook@chromium.org
Link: http://lkml.kernel.org/r/20171221104205.7269-27-anna-maria@linutronix.de
Signed-off-by: Ingo Molnar

hrtimer: Make hrtimer_reprogramm() unconditional

2018-01-16T01:35:47+00:00

hrtimer_reprogram() needs to be available unconditionally for softirq based
hrtimers. Move the function and all required struct members out of the
CONFIG_HIGH_RES_TIMERS #ifdef.

There is no functional change because hrtimer_reprogram() is only invoked
when hrtimer_cpu_base.hres_active is true. Making it unconditional
increases the text size for the CONFIG_HIGH_RES_TIMERS=n case, but avoids
replication of that code for the upcoming softirq based hrtimers support.

Signed-off-by: Anna-Maria Gleixner 
Cc: Christoph Hellwig 
Cc: John Stultz 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: keescook@chromium.org
Link: http://lkml.kernel.org/r/20171221104205.7269-18-anna-maria@linutronix.de
Signed-off-by: Ingo Molnar