[PATCH v6 0/6] timers: Use timer_shutdown*() before freeing timers

[Steven Rostedt <rostedt@goodmis.org>]

This is just the patches to implement the infrastructure of the
timer_shutdown_sync() and timer_shutdown(). I'll leave the scripting for the
second stage if this is approved.

Changes since the v5a: https://lore.kernel.org/all/20221106054535.709068702@goodmis.org/

- Broke up the implementation patch into three patches:

  1. The code taken from Thomas and tweaked to compile and added comments,
     as well as changing the name to timer_shutdown_sync():
     https://lore.kernel.org/all/20221106054535.709068702@goodmis.org/

  2. Addition of timer_shutdown() that is like del_timer() but uses the same
     logic as timer_shutdown_sync() to disable the timer after it is called.

  3. Update the documentation to reflect the new APIs.

Steven Rostedt (Google) (6):
      ARM: spear: Do not use timer namespace for timer_shutdown() function
      clocksource/drivers/arm_arch_timer: Do not use timer namespace for timer_shutdown() function
      clocksource/drivers/sp804: Do not use timer namespace for timer_shutdown() function
      timers: Add timer_shutdown_sync() to be called before freeing timers
      timers: Add timer_shutdown() to be called before freeing timers
      timers: Update the documentation to reflect on the new timer_shutdown() API

----
 .../RCU/Design/Requirements/Requirements.rst       |  2 +-
 Documentation/core-api/local_ops.rst               |  2 +-
 Documentation/kernel-hacking/locking.rst           |  5 ++
 arch/arm/mach-spear/time.c                         |  8 +--
 drivers/clocksource/arm_arch_timer.c               | 12 ++--
 drivers/clocksource/timer-sp804.c                  |  6 +-
 include/linux/timer.h                              | 62 +++++++++++++++++++--
 kernel/time/timer.c                                | 64 ++++++++++++----------
 8 files changed, 110 insertions(+), 51 deletions(-)