These are some pointers to timing and timer related files in the Linux kernel.
kernel/time/time.c- Contains basic time related system
kernel/time/timer.c- Legacy timer subsystem based on timer wheels.
kernel/time/hrtimer.c- High resolution timers subsystem
(this is the basis for high resolution kernel timers as well as most current
userspace timer iterfaces:
and POSIX timers)
kernel/time/tick-common.c- Functions for handling of
ticks when they occur, including
tick_periodic for periodic
kernel/time/tick-oneshot.c- Functions for handling of ticks on oneshot based systems.
kernel/time/tick-broadcast.c- Functions for handling the broadcast of tick events for SMP systems, including functions for handling ticks in oneshot mode.