Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer and clockevent updates from Thomas Gleixner:
 "The time(r) core and clockevent updates are mostly boring this time:

   - A new driver for the Tegra210 timer

   - Small fixes and improvements alll over the place

   - Documentation updates and cleanups"

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (22 commits)
  soc/tegra: default select TEGRA_TIMER for Tegra210
  clocksource/drivers/tegra: Add Tegra210 timer support
  dt-bindings: timer: add Tegra210 timer
  clocksource/drivers/timer-cs5535: Rename the file for consistency
  clocksource/drivers/timer-pxa: Rename the file for consistency
  clocksource/drivers/tango-xtal: Rename the file for consistency
  dt-bindings: timer: gpt: update binding doc
  clocksource/drivers/exynos_mct: Remove unused header includes
  dt-bindings: timer: mediatek: update bindings for MT7629 SoC
  clocksource/drivers/exynos_mct: Fix error path in timer resources initialization
  clocksource/drivers/exynos_mct: Remove dead code
  clocksource/drivers/riscv: Add required checks during clock source init
  dt-bindings: timer: renesas: tmu: Document r8a774c0 bindings
  dt-bindings: timer: renesas, cmt: Document r8a774c0 CMT support
  clocksource/drivers/exynos_mct: Clear timer interrupt when shutdown
  clocksource/drivers/exynos_mct: Move one-shot check from tick clear to ISR
  clocksource/drivers/arch_timer: Workaround for Allwinner A64 timer instability
  clocksource/drivers/sun5i: Fail gracefully when clock rate is unavailable
  timers: Mark expected switch fall-throughs
  timekeeping/debug: No need to check return value of debugfs_create functions
  ...

1 files changed, 29 insertions, 0 deletions

diff --git a/kernel/time/Kconfig b/kernel/time/Kconfig
index 58b981f4bb5d..e2c038d6c13c 100644
--- a/kernel/time/Kconfig
+++ b/kernel/time/Kconfig
@@ -117,6 +117,35 @@ config NO_HZ_FULL
 
 endchoice
 
+config CONTEXT_TRACKING
+       bool
+
+config CONTEXT_TRACKING_FORCE
+	bool "Force context tracking"
+	depends on CONTEXT_TRACKING
+	default y if !NO_HZ_FULL
+	help
+	  The major pre-requirement for full dynticks to work is to
+	  support the context tracking subsystem. But there are also
+	  other dependencies to provide in order to make the full
+	  dynticks working.
+
+	  This option stands for testing when an arch implements the
+	  context tracking backend but doesn't yet fullfill all the
+	  requirements to make the full dynticks feature working.
+	  Without the full dynticks, there is no way to test the support
+	  for context tracking and the subsystems that rely on it: RCU
+	  userspace extended quiescent state and tickless cputime
+	  accounting. This option copes with the absence of the full
+	  dynticks subsystem by forcing the context tracking on all
+	  CPUs in the system.
+
+	  Say Y only if you're working on the development of an
+	  architecture backend for the context tracking.
+
+	  Say N otherwise, this option brings an overhead that you
+	  don't want in production.
+
 config NO_HZ
 	bool "Old Idle dynticks config"
 	depends on !ARCH_USES_GETTIMEOFFSET && GENERIC_CLOCKEVENTS