kernel/time/Kconfig

   1 #
   2 # Timer subsystem related configuration options
   3 #
   4
   5 # Options selectable by arch Kconfig
   6
   7 # Watchdog function for clocksources to detect instabilities
   8 config CLOCKSOURCE_WATCHDOG
   9         bool
  10
  11 # Architecture has extra clocksource data
  12 config ARCH_CLOCKSOURCE_DATA
  13         bool
  14
  15 # Timekeeping vsyscall support
  16 config GENERIC_TIME_VSYSCALL
  17         bool
  18
  19 # ktime_t scalar 64bit nsec representation
  20 config KTIME_SCALAR
  21         bool
  22
  23 # Old style timekeeping
  24 config ARCH_USES_GETTIMEOFFSET
  25         bool
  26
  27 # The generic clock events infrastructure
  28 config GENERIC_CLOCKEVENTS
  29         bool
  30
  31 # Migration helper. Builds, but does not invoke
  32 config GENERIC_CLOCKEVENTS_BUILD
  33         bool
  34         default y
  35         depends on GENERIC_CLOCKEVENTS
  36
  37 # Clockevents broadcasting infrastructure
  38 config GENERIC_CLOCKEVENTS_BROADCAST
  39         bool
  40         depends on GENERIC_CLOCKEVENTS
  41
  42 # Automatically adjust the min. reprogramming time for
  43 # clock event device
  44 config GENERIC_CLOCKEVENTS_MIN_ADJUST
  45         bool
  46
  47 # Generic update of CMOS clock
  48 config GENERIC_CMOS_UPDATE
  49         bool
  50
  51 if GENERIC_CLOCKEVENTS
  52 menu "Timers subsystem"
  53
  54 # Core internal switch. Selected by NO_HZ / HIGH_RES_TIMERS. This is
  55 # only related to the tick functionality. Oneshot clockevent devices
  56 # are supported independ of this.
  57 config TICK_ONESHOT
  58         bool
  59
  60 config NO_HZ
  61         bool "Tickless System (Dynamic Ticks)"
  62         depends on !ARCH_USES_GETTIMEOFFSET && GENERIC_CLOCKEVENTS
  63         select TICK_ONESHOT
  64         help
  65           This option enables a tickless system: timer interrupts will
  66           only trigger on an as-needed basis both when the system is
  67           busy and when the system is idle.
  68
  69 config HIGH_RES_TIMERS
  70         bool "High Resolution Timer Support"
  71         depends on !ARCH_USES_GETTIMEOFFSET && GENERIC_CLOCKEVENTS
  72         select TICK_ONESHOT
  73         help
  74           This option enables high resolution timer support. If your
  75           hardware is not capable then this option only increases
  76           the size of the kernel image.
  77
  78 endmenu
  79 endif