/*
* linux/kernel/hrtimer.c
*
* Copyright(C) 2005-2006, Thomas Gleixner <tglx@linutronix.de>
* Copyright(C) 2005-2007, Red Hat, Inc., Ingo Molnar
* Copyright(C) 2006-2007 Timesys Corp., Thomas Gleixner
*
* High-resolution kernel timers
*
* In contrast to the low-resolution timeout API implemented in
* kernel/timer.c, hrtimers provide finer resolution and accuracy
* depending on system configuration and capabilities.
*
* These timers are currently used for:
* - itimers
* - POSIX timers
* - nanosleep
* - precise in-kernel timing
*
* Started by: Thomas Gleixner and Ingo Molnar
*
* Credits:
* based on kernel/timer.c
*
* Help, testing, suggestions, bugfixes, improvements were
* provided by:
*
* George Anzinger, Andrew Morton, Steven Rostedt, Roman Zippel
* et. al.
*
* For licencing details see kernel-base/COPYING
*/
#include <linux/cpu.h>
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/percpu.h>
#include <linux/hrtimer.h>
#include <linux/notifier.h>
#include <linux/syscalls.h>
#include <linux/kallsyms.h>
#include <linux/interrupt.h>
#include <linux/tick.h>
#include <linux/seq_file.h>
#include <linux/err.h>
#include <asm/uaccess.h>
/**
* ktime_get - get the monotonic time in ktime_t format
*
* returns the time in ktime_t format
*/
ktime_t ktime_get(void)
{
struct timespec now;
ktime_get_ts(&now);
return timespec_to_ktime(now);
}
EXPORT_SYMBOL_GPL(ktime_get);
/**
* ktime_get_real - get the real (wall-) time in ktime_t format
*
* returns the time in ktime_t format
*/
ktime_t ktime_get_real(void)
{
struct timespec now;
getnstimeofday(&now);
return timespec_to_ktime(now);
}
EXPORT_SYMBOL_GPL(ktime_get_real);
/*
* The timer bases:
*
* Note: If we want to add new timer bases, we have to skip the two
* clock ids captured by the cpu-timers. We do this by holding empty
* entries rather than doing math adjustment of the clock ids.
* This ensures that we capture erroneous accesses to these clock ids
* rather than moving them into the range of valid clock id's.
*/
DEFINE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases) =
{
.clock_base =
{
{
.index = CLOCK_REALTIME,
.get_time = &ktime_get_real<