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| author | Anna-Maria Behnsen <anna-maria@linutronix.de> | 2025-05-19 10:33:20 +0200 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2025-06-19 14:28:22 +0200 |
| commit | 9094c72c3d81bf2416b7c79d12c8494ab8fbac20 (patch) | |
| tree | fcc75df4a0607f171276a975076cf2fcc803d166 /kernel | |
| parent | timekeeping: Introduce timekeeper ID (diff) | |
| download | linux-9094c72c3d81bf2416b7c79d12c8494ab8fbac20.tar.gz linux-9094c72c3d81bf2416b7c79d12c8494ab8fbac20.zip | |
time: Introduce auxiliary POSIX clocks
To support auxiliary timekeeping and the related user space interfaces,
it's required to define a clock ID range for them.
Reserve 8 auxiliary clock IDs after the regular timekeeping clock ID space.
This is the maximum number of auxiliary clocks the kernel can support. The actual
number of supported clocks depends obviously on the presence of related devices
and might be constraint by the available VDSO space.
Add the corresponding timekeeper IDs as well.
Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: John Stultz <jstultz@google.com>
Link: https://lore.kernel.org/all/20250519083025.905800695@linutronix.de
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/time/Kconfig | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/kernel/time/Kconfig b/kernel/time/Kconfig index b0b97a60aaa6..7c6a52f7836c 100644 --- a/kernel/time/Kconfig +++ b/kernel/time/Kconfig @@ -82,9 +82,9 @@ config CONTEXT_TRACKING_IDLE help Tracks idle state on behalf of RCU. -if GENERIC_CLOCKEVENTS menu "Timers subsystem" +if GENERIC_CLOCKEVENTS # Core internal switch. Selected by NO_HZ_COMMON / HIGH_RES_TIMERS. This is # only related to the tick functionality. Oneshot clockevent devices # are supported independent of this. @@ -208,6 +208,17 @@ config CLOCKSOURCE_WATCHDOG_MAX_SKEW_US interval and NTP's maximum frequency drift of 500 parts per million. If the clocksource is good enough for NTP, it is good enough for the clocksource watchdog! +endif + +config POSIX_AUX_CLOCKS + bool "Enable auxiliary POSIX clocks" + depends on POSIX_TIMERS + help + Auxiliary POSIX clocks are clocks which can be steered + independently of the core timekeeper, which controls the + MONOTONIC, REALTIME, BOOTTIME and TAI clocks. They are useful to + provide e.g. lockless time accessors to independent PTP clocks + and other clock domains, which are not correlated to the TAI/NTP + notion of time. endmenu -endif |