Lines Matching +full:one +full:- +full:timer +full:- +full:only

32 Kernel uses several types of time-related devices, such as: real time clocks,
39 periodically, to run different time-based events.
42 Kernel uses time-based events for many different purposes: scheduling,
47 .Bl -tag -width ".Fn hardclock"
63 Different platforms provide different kinds of timer hardware.
65 that hardware, and to use it, supplying kernel with all required time-based
72 .Bd -literal
89 .Bl -inset
92 bitmask, defining event timer capabilities:
93 .Bl -tag -offset indent -width indent -compact
97 one-shot mode supported,
99 timer is per-CPU,
101 timer may stop when CPU goes to sleep state,
103 timer supports only power-of-2 divisors.
107 timer base frequency,
110 integral value, defining how good is this timer, comparing to others.
113 Timers management code of the kernel chooses one timer from that list.
115 .Va kern.eventtimer.timer
117 Several other tunables/sysctls are affecting how exactly this timer is used:
118 .Bl -inset
120 allows to choose periodic and one-shot operation mode.
121 In periodic mode, periodic interrupts from timer hardware are taken as the
122 only source of time for time events.
123 One-shot mode instead uses currently selected time counter to precisely
124 schedule all needed events and programs event timer to generate interrupt
126 Default value depends of chosen timer capabilities, but one-shot mode is
129 in periodic mode specifies how much times higher timer frequency should be,
138 makes each CPU to receive every timer interrupt independently of whether they
141 If chosen timer is per-CPU
142 and runs in periodic mode, this option has no effect - all interrupts are