hrtimers: Make callback function pointer private

Make the struct hrtimer::function field private, to prevent users from
changing this field in an unsafe way. hrtimer_update_function() should be
used

hrtimers: Make callback function pointer private

Make the struct hrtimer::function field private, to prevent users from
changing this field in an unsafe way. hrtimer_update_function() should be
used if the callback function needs to be changed.

Signed-off-by: Nam Cao <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Link: https://lore.kernel.org/all/7d0e6e0c5c59a64a9bea940051aac05d750bc0c2.1738746927.git.namcao@linutronix.de

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timer_list: Don't use %pK through printk()

This reverts commit f590308536db ("timer debug: Hide kernel addresses via
%pK in /proc/timer_list")

The timer list helper SEQ_printf() uses either the rea

timer_list: Don't use %pK through printk()

This reverts commit f590308536db ("timer debug: Hide kernel addresses via
%pK in /proc/timer_list")

The timer list helper SEQ_printf() uses either the real seq_printf() for
procfs output or vprintk() to print to the kernel log, when invoked from
SysRq-q. It uses %pK for printing pointers.

In the past %pK was prefered over %p as it would not leak raw pointer
values into the kernel log. Since commit ad67b74d2469 ("printk: hash
addresses printed with %p") the regular %p has been improved to avoid this
issue.

Furthermore, restricted pointers ("%pK") were never meant to be used
through printk(). They can still unintentionally leak raw pointers or
acquire sleeping looks in atomic contexts.

Switch to the regular pointer formatting which is safer, easier to reason
about and sufficient here.

Signed-off-by: Thomas Weißschuh <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Link: https://lore.kernel.org/lkml/20250113171731-dc10e3c1-da64-4af0-b767-7c7070468023@linutronix.de/
Link: https://lore.kernel.org/all/20250311-restricted-pointers-timer-v1-1-6626b91e54ab@linutronix.de

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tick: Split nohz and highres features from nohz_mode

The nohz mode field tells about low resolution nohz mode or high
resolution nohz mode but it doesn't tell about high resolution non-nohz
mode.

I

tick: Split nohz and highres features from nohz_mode

The nohz mode field tells about low resolution nohz mode or high
resolution nohz mode but it doesn't tell about high resolution non-nohz
mode.

In order to retrieve the latter state, tick_cancel_sched_timer() must
fiddle with struct hrtimer's internals to guess if the tick has been
initialized in high resolution.

Move instead the nohz mode field information into the tick flags and
provide two new bits: one to know if the tick is in nohz mode and
another one to know if the tick is in high resolution. The combination
of those two flags provides all the needed informations to determine
which of the three tick modes is running.

Signed-off-by: Frederic Weisbecker <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Reviewed-by: Thomas Gleixner <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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tick: Move individual bit features to debuggable mask accesses

The individual bitfields of struct tick_sched must be modified from
IRQs disabled places, otherwise local modifications can race due to

tick: Move individual bit features to debuggable mask accesses

The individual bitfields of struct tick_sched must be modified from
IRQs disabled places, otherwise local modifications can race due to them
sharing the same memory storage.

The recent move of the "got_idle_tick" bitfield to its own storage shows
that the use of these bitfields, as pretty as they look, can be as much
error prone.

In order to avoid future issues of the like and make sure that those
bitfields are safely accessed, move those flags to an explicit mask
along with a mutator function performing the basic IRQs disabled sanity
check.

Signed-off-by: Frederic Weisbecker <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Reviewed-by: Thomas Gleixner <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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timer_list: Print name of per-cpu wakeup device

With the introduction of per-cpu wakeup devices that can be used in
preference to the broadcast timer, print the name of such devices when
they are av

timer_list: Print name of per-cpu wakeup device

With the introduction of per-cpu wakeup devices that can be used in
preference to the broadcast timer, print the name of such devices when
they are available.

Signed-off-by: Will Deacon <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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timer_list: Use printk format instead of open-coded symbol lookup

Use the "%ps" printk format string to resolve symbol names.

This works on all platforms, including ia64, ppc64 and parisc64 on whic

timer_list: Use printk format instead of open-coded symbol lookup

Use the "%ps" printk format string to resolve symbol names.

This works on all platforms, including ia64, ppc64 and parisc64 on which
one needs to dereference pointers to function descriptors instead of
function pointers.

Signed-off-by: Helge Deller <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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timer_list: Guard procfs specific code

With CONFIG_PROC_FS=n the following warning is emitted:

kernel/time/timer_list.c:361:36: warning: unused variable
'timer_list_sops' [-Wunused-const-variable]

timer_list: Guard procfs specific code

With CONFIG_PROC_FS=n the following warning is emitted:

kernel/time/timer_list.c:361:36: warning: unused variable
'timer_list_sops' [-Wunused-const-variable]
static const struct seq_operations timer_list_sops = {

Add #ifdef guard around procfs specific code.

Signed-off-by: Nathan Huckleberry <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Reviewed-by: Nick Desaulniers <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Link: https://github.com/ClangBuiltLinux/linux/issues/534
Link: https://lkml.kernel.org/r/[email protected]

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hrtimers/tick/clockevents: Remove sloppy license references

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

Signe

hrtimers/tick/clockevents: Remove sloppy license references

"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 <[email protected]>
Acked-by: Kees Cook <[email protected]>
Acked-by: Ingo Molnar <[email protected]>
Acked-by: John Stultz <[email protected]>
Acked-by: Corey Minyard <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Kate Stewart <[email protected]>
Cc: Philippe Ombredanne <[email protected]>
Cc: Peter Anvin <[email protected]>
Cc: Russell King <[email protected]>
Cc: Richard Cochran <[email protected]>
Cc: "Paul E. McKenney" <[email protected]>
Cc: Nicolas Pitre <[email protected]>
Cc: David Riley <[email protected]>
Cc: Colin Cross <[email protected]>
Cc: Mark Brown <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]

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time: Add SPDX license identifiers

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

time: Add SPDX license identifiers

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 <[email protected]>
Acked-by: Kees Cook <[email protected]>
Acked-by: Ingo Molnar <[email protected]>
Acked-by: John Stultz <[email protected]>
Acked-by: Corey Minyard <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Kate Stewart <[email protected]>
Cc: Philippe Ombredanne <[email protected]>
Cc: Russell King <[email protected]>
Cc: Richard Cochran <[email protected]>
Cc: Nicolas Pitre <[email protected]>
Cc: David Riley <[email protected]>
Cc: Colin Cross <[email protected]>
Cc: Mark Brown <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Paul E. McKenney <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]

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time: Remove useless filenames in top level comments

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
commen

time: Remove useless filenames in top level comments

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 <[email protected]>
Acked-by: Nicolas Pitre <[email protected]>
Acked-by: Kees Cook <[email protected]>
Acked-by: Ingo Molnar <[email protected]>
Acked-by: John Stultz <[email protected]>
Acked-by: Corey Minyard <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Kate Stewart <[email protected]>
Cc: Philippe Ombredanne <[email protected]>
Cc: Peter Anvin <[email protected]>
Cc: Russell King <[email protected]>
Cc: Richard Cochran <[email protected]>
Cc: "Paul E. McKenney" <[email protected]>
Cc: David Riley <[email protected]>
Cc: Colin Cross <[email protected]>
Cc: Mark Brown <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]

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proc: introduce proc_create_seq_private

Variant of proc_create_data that directly take a struct seq_operations
argument + a private state size and drastically reduces the boilerplate
code in the cal

proc: introduce proc_create_seq_private

Variant of proc_create_data that directly take a struct seq_operations
argument + a private state size and drastically reduces the boilerplate
code in the callers.

All trivial callers converted over.

Signed-off-by: Christoph Hellwig <[email protected]>

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timer_list: Remove unused function pointer typedef

Remove the 'printf_fn_t' typedef as it is not used.

Signed-off-by: Chen Lin <[email protected]>
Signed-off-by: Thomas Gleixner <tglx@linutronix

timer_list: Remove unused function pointer typedef

Remove the 'printf_fn_t' typedef as it is not used.

Signed-off-by: Chen Lin <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Cc: [email protected]
Cc: [email protected]
Link: https://lkml.kernel.org/r/[email protected]

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timer/debug: Change /proc/timer_list from 0444 to 0400

While it uses %pK, there's still few reasons to read this file
as non-root.

Suggested-by: Linus Torvalds <[email protected]>
Acked

timer/debug: Change /proc/timer_list from 0444 to 0400

While it uses %pK, there's still few reasons to read this file
as non-root.

Suggested-by: Linus Torvalds <[email protected]>
Acked-by: Thomas Gleixner <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: [email protected]
Signed-off-by: Ingo Molnar <[email protected]>

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sysrq: Reset the watchdog timers while displaying high-resolution timers

On systems with a large number of CPUs, running sysrq-<q> can cause
watchdog timeouts. There are two slow sections of code i

sysrq: Reset the watchdog timers while displaying high-resolution timers

On systems with a large number of CPUs, running sysrq-<q> can cause
watchdog timeouts. There are two slow sections of code in the sysrq-<q>
path in timer_list.c.

1. print_active_timers() - This function is called by print_cpu() and
contains a slow goto loop. On a machine with hundreds of CPUs, this
loop took approximately 100ms for the first CPU in a NUMA node.
(Subsequent CPUs in the same node ran much quicker.) The total time
to print all of the CPUs is ultimately long enough to trigger the
soft lockup watchdog.

2. print_tickdevice() - This function outputs a large amount of textual
information. This function also took approximately 100ms per CPU.

Since sysrq-<q> is not a performance critical path, there should be no
harm in touching the nmi watchdog in both slow sections above. Touching
it in just one location was insufficient on systems with hundreds of
CPUs as occasional timeouts were still observed during testing.

This issue was observed on an Oracle T7 machine with 128 CPUs, but I
anticipate it may affect other systems with similarly large numbers of
CPUs.

Signed-off-by: Tom Hromatka <[email protected]>
Reviewed-by: Rob Gardner <[email protected]>
Signed-off-by: John Stultz <[email protected]>

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timer_list: Remove useless cast when printing

hrtimer_resolution is already unsigned int, not necessary to cast
it when printing.

Signed-off-by: Mars Cheng <[email protected]>
Cc: CC Hwang <c

timer_list: Remove useless cast when printing

hrtimer_resolution is already unsigned int, not necessary to cast
it when printing.

Signed-off-by: Mars Cheng <[email protected]>
Cc: CC Hwang <[email protected]>
Cc: [email protected]
Cc: Loda Chou <[email protected]>
Cc: Jades Shih <[email protected]>
Cc: Miles Chen <[email protected]>
Cc: John Stultz <[email protected]>
Cc: My Chuang <[email protected]>
Cc: Matthias Brugger <[email protected]>
Cc: Yingjoe Chen <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Thomas Gleixner <[email protected]>

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time: Remove CONFIG_TIMER_STATS

Currently CONFIG_TIMER_STATS exposes process information across namespaces:

kernel/time/timer_list.c print_timer():

SEQ_printf(m, ", %s/%d", tmp, timer->sta

time: Remove CONFIG_TIMER_STATS

Currently CONFIG_TIMER_STATS exposes process information across namespaces:

kernel/time/timer_list.c print_timer():

SEQ_printf(m, ", %s/%d", tmp, timer->start_pid);

/proc/timer_list:

#11: <0000000000000000>, hrtimer_wakeup, S:01, do_nanosleep, cron/2570

Given that the tracer can give the same information, this patch entirely
removes CONFIG_TIMER_STATS.

Suggested-by: Thomas Gleixner <[email protected]>
Signed-off-by: Kees Cook <[email protected]>
Acked-by: John Stultz <[email protected]>
Cc: Nicolas Pitre <[email protected]>
Cc: [email protected]
Cc: Lai Jiangshan <[email protected]>
Cc: Shuah Khan <[email protected]>
Cc: Xing Gao <[email protected]>
Cc: Jonathan Corbet <[email protected]>
Cc: Jessica Frazelle <[email protected]>
Cc: [email protected]
Cc: Nicolas Iooss <[email protected]>
Cc: "Paul E. McKenney" <[email protected]>
Cc: Petr Mladek <[email protected]>
Cc: Richard Cochran <[email protected]>
Cc: Tejun Heo <[email protected]>
Cc: Michal Marek <[email protected]>
Cc: Josh Poimboeuf <[email protected]>
Cc: Dmitry Vyukov <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: "Eric W. Biederman" <[email protected]>
Cc: Olof Johansson <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: [email protected]
Cc: Arjan van de Ven <[email protected]>
Link: http://lkml.kernel.org/r/20170208192659.GA32582@beast
Signed-off-by: Thomas Gleixner <[email protected]>

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Replace <asm/uaccess.h> with <linux/uaccess.h> globally

This was entirely automated, using the script by Al:

PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
sed -i -e "s!$PA

Replace <asm/uaccess.h> with <linux/uaccess.h> globally

This was entirely automated, using the script by Al:

PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
$(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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hrtimer: Handle remaining time proper for TIME_LOW_RES

If CONFIG_TIME_LOW_RES is enabled we add a jiffie to the relative timeout to
prevent short sleeps, but we do not account for that in interfaces

hrtimer: Handle remaining time proper for TIME_LOW_RES

If CONFIG_TIME_LOW_RES is enabled we add a jiffie to the relative timeout to
prevent short sleeps, but we do not account for that in interfaces which
retrieve the remaining time.

Helge observed that timerfd can return a remaining time larger than the
relative timeout. That's not expected and breaks userland test programs.

Store the information that the timer was armed relative and provide functions
to adjust the remaining time. To avoid bloating the hrtimer struct make state
a u8, which as a bonus results in better code on x86 at least.

Reported-and-tested-by: Helge Deller <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: John Stultz <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Thomas Gleixner <[email protected]>

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clockevents: Remove unused set_mode() callback

All users are migrated to the per-state callbacks, get rid of the
unused interface and the core support code.

Signed-off-by: Viresh Kumar <viresh.kuma

clockevents: Remove unused set_mode() callback

All users are migrated to the per-state callbacks, get rid of the
unused interface and the core support code.

Signed-off-by: Viresh Kumar <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Cc: [email protected]
Cc: John Stultz <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Link: http://lkml.kernel.org/r/fd60de14cf6d125489c031207567bb255ad946f6.1441943991.git.viresh.kumar@linaro.org
Signed-off-by: Ingo Molnar <[email protected]>

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timer_list: Add the base offset so remaining nsecs are accurate for non monotonic timers

I noticed for non-monotonic timers in timer_list, some of the
output looked a little confusing.

For example:

timer_list: Add the base offset so remaining nsecs are accurate for non monotonic timers

I noticed for non-monotonic timers in timer_list, some of the
output looked a little confusing.

For example:
#1: <0000000000000000>, posix_timer_fn, S:01, hrtimer_start_range_ns, leap-a-day/2360
# expires at 1434412800000000000-1434412800000000000 nsecs [in 1434410725062375469 to 1434410725062375469 nsecs]

You'll note the relative time till the expiration "[in xxx to
yyy nsecs]" is incorrect. This is because its printing the delta
between CLOCK_MONOTONIC time to the CLOCK_REALTIME expiration.

This patch fixes this issue by adding the clock offset to the
"now" time which we use to calculate the delta.

Cc: Prarit Bhargava <[email protected]>
Cc: Daniel Bristot de Oliveira <[email protected]>
Cc: Richard Cochran <[email protected]>
Cc: Jan Kara <[email protected]>
Cc: Jiri Bohac <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Shuah Khan <[email protected]>
Signed-off-by: John Stultz <[email protected]>

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timer: Reduce timer migration overhead if disabled

Eric reported that the timer_migration sysctl is not really nice
performance wise as it needs to check at every timer insertion whether
the feature

timer: Reduce timer migration overhead if disabled

Eric reported that the timer_migration sysctl is not really nice
performance wise as it needs to check at every timer insertion whether
the feature is enabled or not. Further the check does not live in the
timer code, so we have an extra function call which checks an extra
cache line to figure out that it is disabled.

We can do better and store that information in the per cpu (hr)timer
bases. I pondered to use a static key, but that's a nightmare to
update from the nohz code and the timer base cache line is hot anyway
when we select a timer base.

The old logic enabled the timer migration unconditionally if
CONFIG_NO_HZ was set even if nohz was disabled on the kernel command
line.

With this modification, we start off with migration disabled. The user
visible sysctl is still set to enabled. If the kernel switches to NOHZ
migration is enabled, if the user did not disable it via the sysctl
prior to the switch. If nohz=off is on the kernel command line,
migration stays disabled no matter what.

Before:
47.76% hog [.] main
14.84% [kernel] [k] _raw_spin_lock_irqsave
9.55% [kernel] [k] _raw_spin_unlock_irqrestore
6.71% [kernel] [k] mod_timer
6.24% [kernel] [k] lock_timer_base.isra.38
3.76% [kernel] [k] detach_if_pending
3.71% [kernel] [k] del_timer
2.50% [kernel] [k] internal_add_timer
1.51% [kernel] [k] get_nohz_timer_target
1.28% [kernel] [k] __internal_add_timer
0.78% [kernel] [k] timerfn
0.48% [kernel] [k] wake_up_nohz_cpu

After:
48.10% hog [.] main
15.25% [kernel] [k] _raw_spin_lock_irqsave
9.76% [kernel] [k] _raw_spin_unlock_irqrestore
6.50% [kernel] [k] mod_timer
6.44% [kernel] [k] lock_timer_base.isra.38
3.87% [kernel] [k] detach_if_pending
3.80% [kernel] [k] del_timer
2.67% [kernel] [k] internal_add_timer
1.33% [kernel] [k] __internal_add_timer
0.73% [kernel] [k] timerfn
0.54% [kernel] [k] wake_up_nohz_cpu


Reported-by: Eric Dumazet <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Paul McKenney <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
Cc: Viresh Kumar <[email protected]>
Cc: John Stultz <[email protected]>
Cc: Joonwoo Park <[email protected]>
Cc: Wenbo Wang <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Thomas Gleixner <[email protected]>

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clockevents: Introduce CLOCK_EVT_STATE_ONESHOT_STOPPED state

When no timers/hrtimers are pending, the expiry time is set to a
special value: 'KTIME_MAX'. This normally happens with
NO_HZ_{IDLE|FULL}

clockevents: Introduce CLOCK_EVT_STATE_ONESHOT_STOPPED state

When no timers/hrtimers are pending, the expiry time is set to a
special value: 'KTIME_MAX'. This normally happens with
NO_HZ_{IDLE|FULL} in both LOWRES/HIGHRES modes.

When 'expiry == KTIME_MAX', we either cancel the 'tick-sched' hrtimer
(NOHZ_MODE_HIGHRES) or skip reprogramming clockevent device
(NOHZ_MODE_LOWRES). But, the clockevent device is already
reprogrammed from the tick-handler for next tick.

As the clock event device is programmed in ONESHOT mode it will at
least fire one more time (unnecessarily). Timers on few
implementations (like arm_arch_timer, etc.) only support PERIODIC mode
and their drivers emulate ONESHOT over that. Which means that on these
platforms we will get spurious interrupts periodically (at last
programmed interval rate, normally tick rate).

In order to avoid spurious interrupts, the clockevent device should be
stopped or its interrupts should be masked.

A simple (yet hacky) solution to get this fixed could be: update
hrtimer_force_reprogram() to always reprogram clockevent device and
update clockevent drivers to STOP generating events (or delay it to
max time) when 'expires' is set to KTIME_MAX. But the drawback here is
that every clockevent driver has to be hacked for this particular case
and its very easy for new ones to miss this.

However, Thomas suggested to add an optional state ONESHOT_STOPPED to
solve this problem: lkml.org/lkml/2014/5/9/508.

This patch adds support for ONESHOT_STOPPED state in clockevents
core. It will only be available to drivers that implement the
state-specific callbacks instead of the legacy ->set_mode() callback.

Signed-off-by: Viresh Kumar <[email protected]>
Reviewed-by: Preeti U. Murthy <[email protected]>
Cc: [email protected]
Cc: Frederic Weisbecker <[email protected]>
Cc: Kevin Hilman <[email protected]>
Cc: Daniel Lezcano <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Link: http://lkml.kernel.org/r/b8b383a03ac07b13312c16850b5106b82e4245b5.1428031396.git.viresh.kumar@linaro.org
Signed-off-by: Thomas Gleixner <[email protected]>

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tick-broadcast: Fix the printing of broadcast masks

Today the number of bits of the broadcast masks that is output into
/proc/timer_list is sizeof(unsigned long). This means that on machines
with a

tick-broadcast: Fix the printing of broadcast masks

Today the number of bits of the broadcast masks that is output into
/proc/timer_list is sizeof(unsigned long). This means that on machines
with a larger number of CPUs, the bitmasks of CPUs beyond this range do
not appear.

Fix this by using bitmap printing through "%*pb" instead, so as to
output the broadcast masks for the range of nr_cpu_ids into
/proc/timer_list.

Signed-off-by: Preeti U Murthy <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Thomas Gleixner <[email protected]>

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tick: Nohz: Rework next timer evaluation

The evaluation of the next timer in the nohz code is based on jiffies
while all the tick internals are nano seconds based. We have also to
convert hrtimer na

tick: Nohz: Rework next timer evaluation

The evaluation of the next timer in the nohz code is based on jiffies
while all the tick internals are nano seconds based. We have also to
convert hrtimer nanoseconds to jiffies in the !highres case. That's
just wrong and introduces interesting corner cases.

Turn it around and convert the next timer wheel timer expiry and the
rcu event to clock monotonic and base all calculations on
nanoseconds. That identifies the case where no timer is pending
clearly with an absolute expiry value of KTIME_MAX.

Makes the code more readable and gets rid of the jiffies magic in the
nohz code.

Signed-off-by: Thomas Gleixner <[email protected]>
Reviewed-by: Paul E. McKenney <[email protected]>
Acked-by: Peter Zijlstra <[email protected]>
Cc: Preeti U Murthy <[email protected]>
Cc: Viresh Kumar <[email protected]>
Cc: Marcelo Tosatti <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
Cc: Josh Triplett <[email protected]>
Cc: Lai Jiangshan <[email protected]>
Cc: John Stultz <[email protected]>
Cc: Marcelo Tosatti <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Thomas Gleixner <[email protected]>

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hrtimer: Make the statistics fields smaller

No point in having usigned long for /proc/timer_list statistics. Make
them unsigned int.

Signed-off-by: Thomas Gleixner <[email protected]>
Acked-by: Pe

hrtimer: Make the statistics fields smaller

No point in having usigned long for /proc/timer_list statistics. Make
them unsigned int.

Signed-off-by: Thomas Gleixner <[email protected]>
Acked-by: Peter Zijlstra <[email protected]>
Cc: Preeti U Murthy <[email protected]>
Cc: Viresh Kumar <[email protected]>
Cc: Marcelo Tosatti <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Thomas Gleixner <[email protected]>

show more ...