[PATCH] hrtimer: hrtimer core code
hrtimer subsystem core. It is initialized at bootup and expired by the timer interrupt, but is otherwise not utilized by any other subsystem yet. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Thomas Gleixner
Linus Torvalds
parent
97fc79f97b
commit
c0a3132963
6 changed files with 828 additions and 1 deletions
130
include/linux/hrtimer.h
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130
include/linux/hrtimer.h
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@ -0,0 +1,130 @@
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/*
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* include/linux/hrtimer.h
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*
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* hrtimers - High-resolution kernel timers
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*
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* Copyright(C) 2005, Thomas Gleixner <tglx@linutronix.de>
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* Copyright(C) 2005, Red Hat, Inc., Ingo Molnar
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*
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* data type definitions, declarations, prototypes
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*
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* Started by: Thomas Gleixner and Ingo Molnar
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*
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* For licencing details see kernel-base/COPYING
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*/
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#ifndef _LINUX_HRTIMER_H
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#define _LINUX_HRTIMER_H
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#include <linux/rbtree.h>
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#include <linux/ktime.h>
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#include <linux/init.h>
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#include <linux/list.h>
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#include <linux/wait.h>
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/*
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* Mode arguments of xxx_hrtimer functions:
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*/
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enum hrtimer_mode {
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HRTIMER_ABS, /* Time value is absolute */
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HRTIMER_REL, /* Time value is relative to now */
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};
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enum hrtimer_restart {
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HRTIMER_NORESTART,
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HRTIMER_RESTART,
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};
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/*
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* Timer states:
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*/
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enum hrtimer_state {
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HRTIMER_INACTIVE, /* Timer is inactive */
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HRTIMER_EXPIRED, /* Timer is expired */
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HRTIMER_PENDING, /* Timer is pending */
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};
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struct hrtimer_base;
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/**
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* struct hrtimer - the basic hrtimer structure
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*
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* @node: red black tree node for time ordered insertion
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* @list: list head for easier access to the time ordered list,
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* without walking the red black tree.
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* @expires: the absolute expiry time in the hrtimers internal
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* representation. The time is related to the clock on
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* which the timer is based.
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* @state: state of the timer
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* @function: timer expiry callback function
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* @data: argument for the callback function
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* @base: pointer to the timer base (per cpu and per clock)
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*
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* The hrtimer structure must be initialized by init_hrtimer_#CLOCKTYPE()
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*/
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struct hrtimer {
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struct rb_node node;
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struct list_head list;
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ktime_t expires;
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enum hrtimer_state state;
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int (*function)(void *);
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void *data;
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struct hrtimer_base *base;
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};
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/**
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* struct hrtimer_base - the timer base for a specific clock
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*
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* @index: clock type index for per_cpu support when moving a timer
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* to a base on another cpu.
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* @lock: lock protecting the base and associated timers
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* @active: red black tree root node for the active timers
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* @pending: list of pending timers for simple time ordered access
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* @resolution: the resolution of the clock, in nanoseconds
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* @get_time: function to retrieve the current time of the clock
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* @curr_timer: the timer which is executing a callback right now
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*/
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struct hrtimer_base {
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clockid_t index;
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spinlock_t lock;
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struct rb_root active;
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struct list_head pending;
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unsigned long resolution;
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ktime_t (*get_time)(void);
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struct hrtimer *curr_timer;
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};
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/* Exported timer functions: */
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/* Initialize timers: */
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extern void hrtimer_init(struct hrtimer *timer, const clockid_t which_clock);
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extern void hrtimer_rebase(struct hrtimer *timer, const clockid_t which_clock);
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/* Basic timer operations: */
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extern int hrtimer_start(struct hrtimer *timer, ktime_t tim,
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const enum hrtimer_mode mode);
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extern int hrtimer_cancel(struct hrtimer *timer);
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extern int hrtimer_try_to_cancel(struct hrtimer *timer);
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#define hrtimer_restart(timer) hrtimer_start((timer), (timer)->expires, HRTIMER_ABS)
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/* Query timers: */
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extern ktime_t hrtimer_get_remaining(const struct hrtimer *timer);
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extern int hrtimer_get_res(const clockid_t which_clock, struct timespec *tp);
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static inline int hrtimer_active(const struct hrtimer *timer)
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{
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return timer->state == HRTIMER_PENDING;
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}
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/* Forward a hrtimer so it expires after now: */
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extern unsigned long hrtimer_forward(struct hrtimer *timer,
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const ktime_t interval);
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/* Soft interrupt function to run the hrtimer queues: */
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extern void hrtimer_run_queues(void);
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/* Bootup initialization: */
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extern void __init hrtimers_init(void);
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#endif
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@ -266,4 +266,19 @@ static inline u64 ktime_to_ns(const ktime_t kt)
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#endif
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/*
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* The resolution of the clocks. The resolution value is returned in
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* the clock_getres() system call to give application programmers an
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* idea of the (in)accuracy of timers. Timer values are rounded up to
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* this resolution values.
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*/
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#define KTIME_REALTIME_RES (NSEC_PER_SEC/HZ)
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#define KTIME_MONOTONIC_RES (NSEC_PER_SEC/HZ)
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/* Get the monotonic time in timespec format: */
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extern void ktime_get_ts(struct timespec *ts);
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/* Get the real (wall-) time in timespec format: */
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#define ktime_get_real_ts(ts) getnstimeofday(ts)
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#endif
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@ -485,6 +485,7 @@ asmlinkage void __init start_kernel(void)
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init_IRQ();
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pidhash_init();
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init_timers();
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hrtimers_init();
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softirq_init();
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time_init();
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@ -7,7 +7,8 @@ obj-y = sched.o fork.o exec_domain.o panic.o printk.o profile.o \
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sysctl.o capability.o ptrace.o timer.o user.o \
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signal.o sys.o kmod.o workqueue.o pid.o \
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rcupdate.o intermodule.o extable.o params.o posix-timers.o \
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kthread.o wait.o kfifo.o sys_ni.o posix-cpu-timers.o mutex.o
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kthread.o wait.o kfifo.o sys_ni.o posix-cpu-timers.o mutex.o \
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hrtimer.o
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obj-$(CONFIG_DEBUG_MUTEXES) += mutex-debug.o
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obj-$(CONFIG_FUTEX) += futex.o
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679
kernel/hrtimer.c
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679
kernel/hrtimer.c
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@ -0,0 +1,679 @@
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/*
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* linux/kernel/hrtimer.c
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*
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* Copyright(C) 2005, Thomas Gleixner <tglx@linutronix.de>
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* Copyright(C) 2005, Red Hat, Inc., Ingo Molnar
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*
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* High-resolution kernel timers
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*
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* In contrast to the low-resolution timeout API implemented in
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* kernel/timer.c, hrtimers provide finer resolution and accuracy
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* depending on system configuration and capabilities.
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*
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* These timers are currently used for:
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* - itimers
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* - POSIX timers
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* - nanosleep
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* - precise in-kernel timing
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*
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* Started by: Thomas Gleixner and Ingo Molnar
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*
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* Credits:
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* based on kernel/timer.c
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*
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* For licencing details see kernel-base/COPYING
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*/
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#include <linux/cpu.h>
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#include <linux/module.h>
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#include <linux/percpu.h>
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#include <linux/hrtimer.h>
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#include <linux/notifier.h>
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#include <linux/syscalls.h>
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#include <linux/interrupt.h>
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#include <asm/uaccess.h>
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/**
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* ktime_get - get the monotonic time in ktime_t format
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*
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* returns the time in ktime_t format
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*/
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static ktime_t ktime_get(void)
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{
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struct timespec now;
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ktime_get_ts(&now);
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return timespec_to_ktime(now);
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}
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/**
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* ktime_get_real - get the real (wall-) time in ktime_t format
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*
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* returns the time in ktime_t format
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*/
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static ktime_t ktime_get_real(void)
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{
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struct timespec now;
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getnstimeofday(&now);
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return timespec_to_ktime(now);
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}
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EXPORT_SYMBOL_GPL(ktime_get_real);
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/*
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* The timer bases:
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*/
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#define MAX_HRTIMER_BASES 2
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static DEFINE_PER_CPU(struct hrtimer_base, hrtimer_bases[MAX_HRTIMER_BASES]) =
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{
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{
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.index = CLOCK_REALTIME,
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.get_time = &ktime_get_real,
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.resolution = KTIME_REALTIME_RES,
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},
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{
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.index = CLOCK_MONOTONIC,
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.get_time = &ktime_get,
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.resolution = KTIME_MONOTONIC_RES,
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},
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};
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/**
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* ktime_get_ts - get the monotonic clock in timespec format
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*
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* @ts: pointer to timespec variable
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*
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* The function calculates the monotonic clock from the realtime
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* clock and the wall_to_monotonic offset and stores the result
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* in normalized timespec format in the variable pointed to by ts.
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*/
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void ktime_get_ts(struct timespec *ts)
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{
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struct timespec tomono;
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unsigned long seq;
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do {
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seq = read_seqbegin(&xtime_lock);
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getnstimeofday(ts);
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tomono = wall_to_monotonic;
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} while (read_seqretry(&xtime_lock, seq));
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set_normalized_timespec(ts, ts->tv_sec + tomono.tv_sec,
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ts->tv_nsec + tomono.tv_nsec);
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}
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/*
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* Functions and macros which are different for UP/SMP systems are kept in a
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* single place
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*/
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#ifdef CONFIG_SMP
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#define set_curr_timer(b, t) do { (b)->curr_timer = (t); } while (0)
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/*
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* We are using hashed locking: holding per_cpu(hrtimer_bases)[n].lock
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* means that all timers which are tied to this base via timer->base are
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* locked, and the base itself is locked too.
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*
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* So __run_timers/migrate_timers can safely modify all timers which could
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* be found on the lists/queues.
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*
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* When the timer's base is locked, and the timer removed from list, it is
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* possible to set timer->base = NULL and drop the lock: the timer remains
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* locked.
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*/
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static struct hrtimer_base *lock_hrtimer_base(const struct hrtimer *timer,
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unsigned long *flags)
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{
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struct hrtimer_base *base;
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for (;;) {
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base = timer->base;
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if (likely(base != NULL)) {
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spin_lock_irqsave(&base->lock, *flags);
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if (likely(base == timer->base))
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return base;
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/* The timer has migrated to another CPU: */
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spin_unlock_irqrestore(&base->lock, *flags);
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}
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cpu_relax();
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}
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}
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/*
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* Switch the timer base to the current CPU when possible.
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*/
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static inline struct hrtimer_base *
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switch_hrtimer_base(struct hrtimer *timer, struct hrtimer_base *base)
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{
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struct hrtimer_base *new_base;
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new_base = &__get_cpu_var(hrtimer_bases[base->index]);
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if (base != new_base) {
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/*
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* We are trying to schedule the timer on the local CPU.
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* However we can't change timer's base while it is running,
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* so we keep it on the same CPU. No hassle vs. reprogramming
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* the event source in the high resolution case. The softirq
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* code will take care of this when the timer function has
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* completed. There is no conflict as we hold the lock until
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* the timer is enqueued.
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*/
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if (unlikely(base->curr_timer == timer))
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return base;
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/* See the comment in lock_timer_base() */
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timer->base = NULL;
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spin_unlock(&base->lock);
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spin_lock(&new_base->lock);
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timer->base = new_base;
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}
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return new_base;
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}
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#else /* CONFIG_SMP */
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#define set_curr_timer(b, t) do { } while (0)
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static inline struct hrtimer_base *
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lock_hrtimer_base(const struct hrtimer *timer, unsigned long *flags)
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{
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struct hrtimer_base *base = timer->base;
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spin_lock_irqsave(&base->lock, *flags);
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return base;
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}
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#define switch_hrtimer_base(t, b) (b)
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#endif /* !CONFIG_SMP */
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/*
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* Functions for the union type storage format of ktime_t which are
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* too large for inlining:
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*/
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#if BITS_PER_LONG < 64
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# ifndef CONFIG_KTIME_SCALAR
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/**
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* ktime_add_ns - Add a scalar nanoseconds value to a ktime_t variable
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*
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* @kt: addend
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* @nsec: the scalar nsec value to add
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*
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* Returns the sum of kt and nsec in ktime_t format
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*/
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ktime_t ktime_add_ns(const ktime_t kt, u64 nsec)
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{
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ktime_t tmp;
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if (likely(nsec < NSEC_PER_SEC)) {
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tmp.tv64 = nsec;
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} else {
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unsigned long rem = do_div(nsec, NSEC_PER_SEC);
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tmp = ktime_set((long)nsec, rem);
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}
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return ktime_add(kt, tmp);
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}
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#else /* CONFIG_KTIME_SCALAR */
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# endif /* !CONFIG_KTIME_SCALAR */
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/*
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* Divide a ktime value by a nanosecond value
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*/
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static unsigned long ktime_divns(const ktime_t kt, nsec_t div)
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{
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u64 dclc, inc, dns;
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int sft = 0;
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dclc = dns = ktime_to_ns(kt);
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inc = div;
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/* Make sure the divisor is less than 2^32: */
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while (div >> 32) {
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sft++;
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div >>= 1;
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}
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dclc >>= sft;
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do_div(dclc, (unsigned long) div);
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return (unsigned long) dclc;
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}
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#else /* BITS_PER_LONG < 64 */
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# define ktime_divns(kt, div) (unsigned long)((kt).tv64 / (div))
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#endif /* BITS_PER_LONG >= 64 */
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/*
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* Counterpart to lock_timer_base above:
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*/
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static inline
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void unlock_hrtimer_base(const struct hrtimer *timer, unsigned long *flags)
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{
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spin_unlock_irqrestore(&timer->base->lock, *flags);
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}
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/**
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* hrtimer_forward - forward the timer expiry
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*
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* @timer: hrtimer to forward
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* @interval: the interval to forward
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*
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* Forward the timer expiry so it will expire in the future.
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* The number of overruns is added to the overrun field.
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*/
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unsigned long
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hrtimer_forward(struct hrtimer *timer, const ktime_t interval)
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{
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unsigned long orun = 1;
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ktime_t delta, now;
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now = timer->base->get_time();
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delta = ktime_sub(now, timer->expires);
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if (delta.tv64 < 0)
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return 0;
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if (unlikely(delta.tv64 >= interval.tv64)) {
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nsec_t incr = ktime_to_ns(interval);
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orun = ktime_divns(delta, incr);
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timer->expires = ktime_add_ns(timer->expires, incr * orun);
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if (timer->expires.tv64 > now.tv64)
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return orun;
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/*
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* This (and the ktime_add() below) is the
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* correction for exact:
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*/
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orun++;
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}
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timer->expires = ktime_add(timer->expires, interval);
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return orun;
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}
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/*
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* enqueue_hrtimer - internal function to (re)start a timer
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*
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* The timer is inserted in expiry order. Insertion into the
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* red black tree is O(log(n)). Must hold the base lock.
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*/
|
||||
static void enqueue_hrtimer(struct hrtimer *timer, struct hrtimer_base *base)
|
||||
{
|
||||
struct rb_node **link = &base->active.rb_node;
|
||||
struct list_head *prev = &base->pending;
|
||||
struct rb_node *parent = NULL;
|
||||
struct hrtimer *entry;
|
||||
|
||||
/*
|
||||
* Find the right place in the rbtree:
|
||||
*/
|
||||
while (*link) {
|
||||
parent = *link;
|
||||
entry = rb_entry(parent, struct hrtimer, node);
|
||||
/*
|
||||
* We dont care about collisions. Nodes with
|
||||
* the same expiry time stay together.
|
||||
*/
|
||||
if (timer->expires.tv64 < entry->expires.tv64)
|
||||
link = &(*link)->rb_left;
|
||||
else {
|
||||
link = &(*link)->rb_right;
|
||||
prev = &entry->list;
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* Insert the timer to the rbtree and to the sorted list:
|
||||
*/
|
||||
rb_link_node(&timer->node, parent, link);
|
||||
rb_insert_color(&timer->node, &base->active);
|
||||
list_add(&timer->list, prev);
|
||||
|
||||
timer->state = HRTIMER_PENDING;
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
* __remove_hrtimer - internal function to remove a timer
|
||||
*
|
||||
* Caller must hold the base lock.
|
||||
*/
|
||||
static void __remove_hrtimer(struct hrtimer *timer, struct hrtimer_base *base)
|
||||
{
|
||||
/*
|
||||
* Remove the timer from the sorted list and from the rbtree:
|
||||
*/
|
||||
list_del(&timer->list);
|
||||
rb_erase(&timer->node, &base->active);
|
||||
}
|
||||
|
||||
/*
|
||||
* remove hrtimer, called with base lock held
|
||||
*/
|
||||
static inline int
|
||||
remove_hrtimer(struct hrtimer *timer, struct hrtimer_base *base)
|
||||
{
|
||||
if (hrtimer_active(timer)) {
|
||||
__remove_hrtimer(timer, base);
|
||||
timer->state = HRTIMER_INACTIVE;
|
||||
return 1;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
/**
|
||||
* hrtimer_start - (re)start an relative timer on the current CPU
|
||||
*
|
||||
* @timer: the timer to be added
|
||||
* @tim: expiry time
|
||||
* @mode: expiry mode: absolute (HRTIMER_ABS) or relative (HRTIMER_REL)
|
||||
*
|
||||
* Returns:
|
||||
* 0 on success
|
||||
* 1 when the timer was active
|
||||
*/
|
||||
int
|
||||
hrtimer_start(struct hrtimer *timer, ktime_t tim, const enum hrtimer_mode mode)
|
||||
{
|
||||
struct hrtimer_base *base, *new_base;
|
||||
unsigned long flags;
|
||||
int ret;
|
||||
|
||||
base = lock_hrtimer_base(timer, &flags);
|
||||
|
||||
/* Remove an active timer from the queue: */
|
||||
ret = remove_hrtimer(timer, base);
|
||||
|
||||
/* Switch the timer base, if necessary: */
|
||||
new_base = switch_hrtimer_base(timer, base);
|
||||
|
||||
if (mode == HRTIMER_REL)
|
||||
tim = ktime_add(tim, new_base->get_time());
|
||||
timer->expires = tim;
|
||||
|
||||
enqueue_hrtimer(timer, new_base);
|
||||
|
||||
unlock_hrtimer_base(timer, &flags);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
/**
|
||||
* hrtimer_try_to_cancel - try to deactivate a timer
|
||||
*
|
||||
* @timer: hrtimer to stop
|
||||
*
|
||||
* Returns:
|
||||
* 0 when the timer was not active
|
||||
* 1 when the timer was active
|
||||
* -1 when the timer is currently excuting the callback function and
|
||||
* can not be stopped
|
||||
*/
|
||||
int hrtimer_try_to_cancel(struct hrtimer *timer)
|
||||
{
|
||||
struct hrtimer_base *base;
|
||||
unsigned long flags;
|
||||
int ret = -1;
|
||||
|
||||
base = lock_hrtimer_base(timer, &flags);
|
||||
|
||||
if (base->curr_timer != timer)
|
||||
ret = remove_hrtimer(timer, base);
|
||||
|
||||
unlock_hrtimer_base(timer, &flags);
|
||||
|
||||
return ret;
|
||||
|
||||
}
|
||||
|
||||
/**
|
||||
* hrtimer_cancel - cancel a timer and wait for the handler to finish.
|
||||
*
|
||||
* @timer: the timer to be cancelled
|
||||
*
|
||||
* Returns:
|
||||
* 0 when the timer was not active
|
||||
* 1 when the timer was active
|
||||
*/
|
||||
int hrtimer_cancel(struct hrtimer *timer)
|
||||
{
|
||||
for (;;) {
|
||||
int ret = hrtimer_try_to_cancel(timer);
|
||||
|
||||
if (ret >= 0)
|
||||
return ret;
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* hrtimer_get_remaining - get remaining time for the timer
|
||||
*
|
||||
* @timer: the timer to read
|
||||
*/
|
||||
ktime_t hrtimer_get_remaining(const struct hrtimer *timer)
|
||||
{
|
||||
struct hrtimer_base *base;
|
||||
unsigned long flags;
|
||||
ktime_t rem;
|
||||
|
||||
base = lock_hrtimer_base(timer, &flags);
|
||||
rem = ktime_sub(timer->expires, timer->base->get_time());
|
||||
unlock_hrtimer_base(timer, &flags);
|
||||
|
||||
return rem;
|
||||
}
|
||||
|
||||
/**
|
||||
* hrtimer_rebase - rebase an initialized hrtimer to a different base
|
||||
*
|
||||
* @timer: the timer to be rebased
|
||||
* @clock_id: the clock to be used
|
||||
*/
|
||||
void hrtimer_rebase(struct hrtimer *timer, const clockid_t clock_id)
|
||||
{
|
||||
struct hrtimer_base *bases;
|
||||
|
||||
bases = per_cpu(hrtimer_bases, raw_smp_processor_id());
|
||||
timer->base = &bases[clock_id];
|
||||
}
|
||||
|
||||
/**
|
||||
* hrtimer_init - initialize a timer to the given clock
|
||||
*
|
||||
* @timer: the timer to be initialized
|
||||
* @clock_id: the clock to be used
|
||||
*/
|
||||
void hrtimer_init(struct hrtimer *timer, const clockid_t clock_id)
|
||||
{
|
||||
memset(timer, 0, sizeof(struct hrtimer));
|
||||
hrtimer_rebase(timer, clock_id);
|
||||
}
|
||||
|
||||
/**
|
||||
* hrtimer_get_res - get the timer resolution for a clock
|
||||
*
|
||||
* @which_clock: which clock to query
|
||||
* @tp: pointer to timespec variable to store the resolution
|
||||
*
|
||||
* Store the resolution of the clock selected by which_clock in the
|
||||
* variable pointed to by tp.
|
||||
*/
|
||||
int hrtimer_get_res(const clockid_t which_clock, struct timespec *tp)
|
||||
{
|
||||
struct hrtimer_base *bases;
|
||||
|
||||
tp->tv_sec = 0;
|
||||
bases = per_cpu(hrtimer_bases, raw_smp_processor_id());
|
||||
tp->tv_nsec = bases[which_clock].resolution;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Expire the per base hrtimer-queue:
|
||||
*/
|
||||
static inline void run_hrtimer_queue(struct hrtimer_base *base)
|
||||
{
|
||||
ktime_t now = base->get_time();
|
||||
|
||||
spin_lock_irq(&base->lock);
|
||||
|
||||
while (!list_empty(&base->pending)) {
|
||||
struct hrtimer *timer;
|
||||
int (*fn)(void *);
|
||||
int restart;
|
||||
void *data;
|
||||
|
||||
timer = list_entry(base->pending.next, struct hrtimer, list);
|
||||
if (now.tv64 <= timer->expires.tv64)
|
||||
break;
|
||||
|
||||
fn = timer->function;
|
||||
data = timer->data;
|
||||
set_curr_timer(base, timer);
|
||||
__remove_hrtimer(timer, base);
|
||||
spin_unlock_irq(&base->lock);
|
||||
|
||||
/*
|
||||
* fn == NULL is special case for the simplest timer
|
||||
* variant - wake up process and do not restart:
|
||||
*/
|
||||
if (!fn) {
|
||||
wake_up_process(data);
|
||||
restart = HRTIMER_NORESTART;
|
||||
} else
|
||||
restart = fn(data);
|
||||
|
||||
spin_lock_irq(&base->lock);
|
||||
|
||||
if (restart == HRTIMER_RESTART)
|
||||
enqueue_hrtimer(timer, base);
|
||||
else
|
||||
timer->state = HRTIMER_EXPIRED;
|
||||
}
|
||||
set_curr_timer(base, NULL);
|
||||
spin_unlock_irq(&base->lock);
|
||||
}
|
||||
|
||||
/*
|
||||
* Called from timer softirq every jiffy, expire hrtimers:
|
||||
*/
|
||||
void hrtimer_run_queues(void)
|
||||
{
|
||||
struct hrtimer_base *base = __get_cpu_var(hrtimer_bases);
|
||||
int i;
|
||||
|
||||
for (i = 0; i < MAX_HRTIMER_BASES; i++)
|
||||
run_hrtimer_queue(&base[i]);
|
||||
}
|
||||
|
||||
/*
|
||||
* Functions related to boot-time initialization:
|
||||
*/
|
||||
static void __devinit init_hrtimers_cpu(int cpu)
|
||||
{
|
||||
struct hrtimer_base *base = per_cpu(hrtimer_bases, cpu);
|
||||
int i;
|
||||
|
||||
for (i = 0; i < MAX_HRTIMER_BASES; i++) {
|
||||
spin_lock_init(&base->lock);
|
||||
INIT_LIST_HEAD(&base->pending);
|
||||
base++;
|
||||
}
|
||||
}
|
||||
|
||||
#ifdef CONFIG_HOTPLUG_CPU
|
||||
|
||||
static void migrate_hrtimer_list(struct hrtimer_base *old_base,
|
||||
struct hrtimer_base *new_base)
|
||||
{
|
||||
struct hrtimer *timer;
|
||||
struct rb_node *node;
|
||||
|
||||
while ((node = rb_first(&old_base->active))) {
|
||||
timer = rb_entry(node, struct hrtimer, node);
|
||||
__remove_hrtimer(timer, old_base);
|
||||
timer->base = new_base;
|
||||
enqueue_hrtimer(timer, new_base);
|
||||
}
|
||||
}
|
||||
|
||||
static void migrate_hrtimers(int cpu)
|
||||
{
|
||||
struct hrtimer_base *old_base, *new_base;
|
||||
int i;
|
||||
|
||||
BUG_ON(cpu_online(cpu));
|
||||
old_base = per_cpu(hrtimer_bases, cpu);
|
||||
new_base = get_cpu_var(hrtimer_bases);
|
||||
|
||||
local_irq_disable();
|
||||
|
||||
for (i = 0; i < MAX_HRTIMER_BASES; i++) {
|
||||
|
||||
spin_lock(&new_base->lock);
|
||||
spin_lock(&old_base->lock);
|
||||
|
||||
BUG_ON(old_base->curr_timer);
|
||||
|
||||
migrate_hrtimer_list(old_base, new_base);
|
||||
|
||||
spin_unlock(&old_base->lock);
|
||||
spin_unlock(&new_base->lock);
|
||||
old_base++;
|
||||
new_base++;
|
||||
}
|
||||
|
||||
local_irq_enable();
|
||||
put_cpu_var(hrtimer_bases);
|
||||
}
|
||||
#endif /* CONFIG_HOTPLUG_CPU */
|
||||
|
||||
static int __devinit hrtimer_cpu_notify(struct notifier_block *self,
|
||||
unsigned long action, void *hcpu)
|
||||
{
|
||||
long cpu = (long)hcpu;
|
||||
|
||||
switch (action) {
|
||||
|
||||
case CPU_UP_PREPARE:
|
||||
init_hrtimers_cpu(cpu);
|
||||
break;
|
||||
|
||||
#ifdef CONFIG_HOTPLUG_CPU
|
||||
case CPU_DEAD:
|
||||
migrate_hrtimers(cpu);
|
||||
break;
|
||||
#endif
|
||||
|
||||
default:
|
||||
break;
|
||||
}
|
||||
|
||||
return NOTIFY_OK;
|
||||
}
|
||||
|
||||
static struct notifier_block __devinitdata hrtimers_nb = {
|
||||
.notifier_call = hrtimer_cpu_notify,
|
||||
};
|
||||
|
||||
void __init hrtimers_init(void)
|
||||
{
|
||||
hrtimer_cpu_notify(&hrtimers_nb, (unsigned long)CPU_UP_PREPARE,
|
||||
(void *)(long)smp_processor_id());
|
||||
register_cpu_notifier(&hrtimers_nb);
|
||||
}
|
||||
|
||||
|
|
@ -858,6 +858,7 @@ static void run_timer_softirq(struct softirq_action *h)
|
|||
{
|
||||
tvec_base_t *base = &__get_cpu_var(tvec_bases);
|
||||
|
||||
hrtimer_run_queues();
|
||||
if (time_after_eq(jiffies, base->timer_jiffies))
|
||||
__run_timers(base);
|
||||
}
|
||||
|
|
|
|||
Loading…
Reference in a new issue