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 # Timekeeping vsyscall support
  20 config GENERIC_TIME_VSYSCALL_OLD
  21         bool
  22
  23 # ktime_t scalar 64bit nsec representation
  24 config KTIME_SCALAR
  25         bool
  26
  27 # Old style timekeeping
  28 config ARCH_USES_GETTIMEOFFSET
  29         bool
  30
  31 # The generic clock events infrastructure
  32 config GENERIC_CLOCKEVENTS
  33         bool
  34
  35 # Migration helper. Builds, but does not invoke
  36 config GENERIC_CLOCKEVENTS_BUILD
  37         bool
  38         default y
  39         depends on GENERIC_CLOCKEVENTS
  40
  41 # Clockevents broadcasting infrastructure
  42 config GENERIC_CLOCKEVENTS_BROADCAST
  43         bool
  44         depends on GENERIC_CLOCKEVENTS
  45
  46 # Automatically adjust the min. reprogramming time for
  47 # clock event device
  48 config GENERIC_CLOCKEVENTS_MIN_ADJUST
  49         bool
  50
  51 # Generic update of CMOS clock
  52 config GENERIC_CMOS_UPDATE
  53         bool
  54
  55 if GENERIC_CLOCKEVENTS
  56 menu "Timers subsystem"
  57
  58 # Core internal switch. Selected by NO_HZ / HIGH_RES_TIMERS. This is
  59 # only related to the tick functionality. Oneshot clockevent devices
  60 # are supported independ of this.
  61 config TICK_ONESHOT
  62         bool
  63
  64 config NO_HZ
  65         bool "Tickless System (Dynamic Ticks)"
  66         depends on !ARCH_USES_GETTIMEOFFSET && GENERIC_CLOCKEVENTS
  67         select TICK_ONESHOT
  68         help
  69           This option enables a tickless system: timer interrupts will
  70           only trigger on an as-needed basis both when the system is
  71           busy and when the system is idle.
  72
  73 config HIGH_RES_TIMERS
  74         bool "High Resolution Timer Support"
  75         depends on !ARCH_USES_GETTIMEOFFSET && GENERIC_CLOCKEVENTS
  76         select TICK_ONESHOT
  77         help
  78           This option enables high resolution timer support. If your
  79           hardware is not capable then this option only increases
  80           the size of the kernel image.
  81
  82 endmenu
  83 endif