linux.git/include/trace/events/timer.h, branch v6.6.131

tracing/timer: Add missing hrtimer modes to decode_hrtimer_mode().

2023-06-19T07:09:14+00:00

The trace output for the HRTIMER_MODE_.*_HARD modes is seen as a number
since these modes are not decoded. The author was not aware of the fancy
decoding function which makes the life easier.

Extend decode_hrtimer_mode() with the additional HRTIMER_MODE_.*_HARD
modes.

Fixes: ae6683d815895 ("hrtimer: Introduce HARD expiry mode")
Signed-off-by: Sebastian Andrzej Siewior 
Signed-off-by: Thomas Gleixner 
Reviewed-by: Mukesh Ojha 
Acked-by: Steven Rostedt (Google) 
Link: https://lore.kernel.org/r/20230418143854.8vHWQKLM@linutronix.de

rcu: Fix missing TICK_DEP_MASK_RCU_EXP dependency check

2023-04-05T13:47:43+00:00

This commit adds checks for the TICK_DEP_MASK_RCU_EXP bit, thus enabling
RCU expedited grace periods to actually force-enable scheduling-clock
interrupts on holdout CPUs.

Fixes: df1e849ae455 ("rcu: Enable tick for nohz_full CPUs slow to provide expedited QS")
Signed-off-by: Zqiang 
Cc: Steven Rostedt 
Cc: Masami Hiramatsu 
Cc: Frederic Weisbecker 
Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: Anna-Maria Behnsen 
Acked-by: Frederic Weisbecker 
Signed-off-by: Paul E. McKenney 
Signed-off-by: Joel Fernandes (Google)

tracing/timer: Add missing argument documentation of trace points

2022-04-14T14:14:49+00:00

Documentation of trace points timer_start, timer_expire_entry and
hrtimer_start lack always the last argument. Add it to keep implementation
and documentation in sync.

Signed-off-by: Anna-Maria Behnsen 
Signed-off-by: Thomas Gleixner 
Acked-by: Steven Rostedt (Google) 
Link: https://lore.kernel.org/r/20220411140115.24185-1-anna-maria@linutronix.de

tracing: Fix various typos in comments

2021-03-23T18:08:18+00:00

Fix ~59 single-word typos in the tracing code comments, and fix
the grammar in a handful of places.

Link: https://lore.kernel.org/r/20210322224546.GA1981273@gmail.com
Link: https://lkml.kernel.org/r/20210323174935.GA4176821@gmail.com

Reviewed-by: Randy Dunlap 
Signed-off-by: Ingo Molnar 
Signed-off-by: Steven Rostedt (VMware)

Merge tag 'y2038-cleanups-5.5' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground

2019-12-01T22:00:59+00:00

Pull y2038 cleanups from Arnd Bergmann:
 "y2038 syscall implementation cleanups

  This is a series of cleanups for the y2038 work, mostly intended for
  namespace cleaning: the kernel defines the traditional time_t, timeval
  and timespec types that often lead to y2038-unsafe code. Even though
  the unsafe usage is mostly gone from the kernel, having the types and
  associated functions around means that we can still grow new users,
  and that we may be missing conversions to safe types that actually
  matter.

  There are still a number of driver specific patches needed to get the
  last users of these types removed, those have been submitted to the
  respective maintainers"

Link: https://lore.kernel.org/lkml/20191108210236.1296047-1-arnd@arndb.de/

* tag 'y2038-cleanups-5.5' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground: (26 commits)
  y2038: alarm: fix half-second cut-off
  y2038: ipc: fix x32 ABI breakage
  y2038: fix typo in powerpc vdso "LOPART"
  y2038: allow disabling time32 system calls
  y2038: itimer: change implementation to timespec64
  y2038: move itimer reset into itimer.c
  y2038: use compat_{get,set}_itimer on alpha
  y2038: itimer: compat handling to itimer.c
  y2038: time: avoid timespec usage in settimeofday()
  y2038: timerfd: Use timespec64 internally
  y2038: elfcore: Use __kernel_old_timeval for process times
  y2038: make ns_to_compat_timeval use __kernel_old_timeval
  y2038: socket: use __kernel_old_timespec instead of timespec
  y2038: socket: remove timespec reference in timestamping
  y2038: syscalls: change remaining timeval to __kernel_old_timeval
  y2038: rusage: use __kernel_old_timeval
  y2038: uapi: change __kernel_time_t to __kernel_old_time_t
  y2038: stat: avoid 'time_t' in 'struct stat'
  y2038: ipc: remove __kernel_time_t reference from headers
  y2038: vdso: powerpc: avoid timespec references
  ...

y2038: itimer: change implementation to timespec64

2019-11-15T13:38:30+00:00

There is no 64-bit version of getitimer/setitimer since that is not
actually needed. However, the implementation is built around the
deprecated 'struct timeval' type.

Change the code to use timespec64 internally to reduce the dependencies
on timeval and associated helper functions.

Minor adjustments in the code are needed to make the native and compat
version work the same way, and to keep the range check working after
the conversion.

Signed-off-by: Arnd Bergmann

nohz: Add TICK_DEP_BIT_RCU

2019-10-05T17:45:16+00:00

If a nohz_full CPU is looping in the kernel, the scheduling-clock tick
might nevertheless remain disabled.  In !PREEMPT kernels, this can
prevent RCU's attempts to enlist the aid of that CPU's executions of
cond_resched(), which can in turn result in an arbitrarily delayed grace
period and thus an OOM.  RCU therefore needs a way to enable a holdout
nohz_full CPU's scheduler-clock interrupt.

This commit therefore provides a new TICK_DEP_BIT_RCU value which RCU can
pass to tick_dep_set_cpu() and friends to force on the scheduler-clock
interrupt for a specified CPU or task.  In some cases, rcutorture needs
to turn on the scheduler-clock tick, so this commit also exports the
relevant symbols to GPL-licensed modules.

Signed-off-by: Frederic Weisbecker 
Signed-off-by: Paul E. McKenney

timer/trace: Improve timer tracing

2019-03-24T19:29:33+00:00

Timers are added to the timer wheel off by one. This is required in
case a timer is queued directly before incrementing jiffies to prevent
early timer expiry.

When reading a timer trace and relying only on the expiry time of the timer
in the timer_start trace point and on the now in the timer_expiry_entry
trace point, it seems that the timer fires late. With the current
timer_expiry_entry trace point information only now=jiffies is printed but
not the value of base->clk. This makes it impossible to draw a conclusion
to the index of base->clk and makes it impossible to examine timer problems
without additional trace points.

Therefore add the base->clk value to the timer_expire_entry trace
point, to be able to calculate the index the timer base is located at
during collecting expired timers.

Signed-off-by: Anna-Maria Gleixner 
Signed-off-by: Thomas Gleixner 
Cc: fweisbec@gmail.com
Cc: peterz@infradead.org
Cc: Steven Rostedt 
Link: https://lkml.kernel.org/r/20190321120921.16463-5-anna-maria@linutronix.de

timer/trace: Replace deprecated vsprintf pointer extension %pf by %ps

2019-03-24T19:29:33+00:00

Since commit 04b8eb7a4ccd ("symbol lookup: introduce
dereference_symbol_descriptor()") %pf is deprecated, because %ps is smart
enough to handle function pointer dereference on platforms where such a
dereference is required.

While at it add proper line breaks to stay in the 80 character limit.

Signed-off-by: Anna-Maria Gleixner 
Signed-off-by: Thomas Gleixner 
Cc: fweisbec@gmail.com
Cc: peterz@infradead.org
Cc: Steven Rostedt 
Link: https://lkml.kernel.org/r/20190321120921.16463-4-anna-maria@linutronix.de

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