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c1b4098d48
um_timer shouldn't add local_offset to the host time since get_time already did it. This threw off sleep when a settimeofday or equivalent had happened. Signed-off-by: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
181 lines
3.8 KiB
C
181 lines
3.8 KiB
C
/*
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* Copyright (C) 2000 Jeff Dike (jdike@karaya.com)
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* Licensed under the GPL
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*/
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#include "linux/kernel.h"
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#include "linux/module.h"
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#include "linux/unistd.h"
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#include "linux/stddef.h"
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#include "linux/spinlock.h"
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#include "linux/time.h"
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#include "linux/sched.h"
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#include "linux/interrupt.h"
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#include "linux/init.h"
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#include "linux/delay.h"
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#include "linux/hrtimer.h"
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#include "asm/irq.h"
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#include "asm/param.h"
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#include "asm/current.h"
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#include "kern_util.h"
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#include "user_util.h"
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#include "mode.h"
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#include "os.h"
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int hz(void)
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{
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return(HZ);
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}
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/*
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* Scheduler clock - returns current time in nanosec units.
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*/
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unsigned long long sched_clock(void)
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{
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return (unsigned long long)jiffies_64 * (1000000000 / HZ);
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}
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static unsigned long long prev_nsecs;
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#ifdef CONFIG_UML_REAL_TIME_CLOCK
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static long long delta; /* Deviation per interval */
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#endif
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void timer_irq(union uml_pt_regs *regs)
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{
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unsigned long long ticks = 0;
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#ifdef CONFIG_UML_REAL_TIME_CLOCK
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if(prev_nsecs){
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/* We've had 1 tick */
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unsigned long long nsecs = os_nsecs();
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delta += nsecs - prev_nsecs;
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prev_nsecs = nsecs;
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/* Protect against the host clock being set backwards */
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if(delta < 0)
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delta = 0;
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ticks += (delta * HZ) / BILLION;
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delta -= (ticks * BILLION) / HZ;
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}
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else prev_nsecs = os_nsecs();
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#else
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ticks = 1;
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#endif
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while(ticks > 0){
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do_IRQ(TIMER_IRQ, regs);
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ticks--;
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}
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}
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static DEFINE_SPINLOCK(timer_spinlock);
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static unsigned long long local_offset = 0;
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static inline unsigned long long get_time(void)
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{
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unsigned long long nsecs;
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unsigned long flags;
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spin_lock_irqsave(&timer_spinlock, flags);
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nsecs = os_nsecs();
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nsecs += local_offset;
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spin_unlock_irqrestore(&timer_spinlock, flags);
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return nsecs;
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}
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irqreturn_t um_timer(int irq, void *dev, struct pt_regs *regs)
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{
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unsigned long long nsecs;
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unsigned long flags;
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write_seqlock_irqsave(&xtime_lock, flags);
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do_timer(regs);
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nsecs = get_time();
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xtime.tv_sec = nsecs / NSEC_PER_SEC;
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xtime.tv_nsec = nsecs - xtime.tv_sec * NSEC_PER_SEC;
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write_sequnlock_irqrestore(&xtime_lock, flags);
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return IRQ_HANDLED;
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}
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static void register_timer(void)
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{
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int err;
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err = request_irq(TIMER_IRQ, um_timer, IRQF_DISABLED, "timer", NULL);
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if(err != 0)
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printk(KERN_ERR "register_timer : request_irq failed - "
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"errno = %d\n", -err);
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err = set_interval(1);
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if(err != 0)
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printk(KERN_ERR "register_timer : set_interval failed - "
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"errno = %d\n", -err);
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}
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extern void (*late_time_init)(void);
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void time_init(void)
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{
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long long nsecs;
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nsecs = os_nsecs();
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set_normalized_timespec(&wall_to_monotonic, -nsecs / BILLION,
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-nsecs % BILLION);
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late_time_init = register_timer;
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}
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void do_gettimeofday(struct timeval *tv)
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{
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unsigned long long nsecs = get_time();
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tv->tv_sec = nsecs / NSEC_PER_SEC;
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/* Careful about calculations here - this was originally done as
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* (nsecs - tv->tv_sec * NSEC_PER_SEC) / NSEC_PER_USEC
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* which gave bogus (> 1000000) values. Dunno why, suspect gcc
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* (4.0.0) miscompiled it, or there's a subtle 64/32-bit conversion
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* problem that I missed.
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*/
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nsecs -= tv->tv_sec * NSEC_PER_SEC;
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tv->tv_usec = (unsigned long) nsecs / NSEC_PER_USEC;
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}
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static inline void set_time(unsigned long long nsecs)
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{
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unsigned long long now;
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unsigned long flags;
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spin_lock_irqsave(&timer_spinlock, flags);
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now = os_nsecs();
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local_offset = nsecs - now;
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spin_unlock_irqrestore(&timer_spinlock, flags);
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clock_was_set();
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}
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int do_settimeofday(struct timespec *tv)
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{
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set_time((unsigned long long) tv->tv_sec * NSEC_PER_SEC + tv->tv_nsec);
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return 0;
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}
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void timer_handler(int sig, union uml_pt_regs *regs)
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{
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local_irq_disable();
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irq_enter();
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update_process_times(CHOOSE_MODE(
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(UPT_SC(regs) && user_context(UPT_SP(regs))),
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(regs)->skas.is_user));
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irq_exit();
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local_irq_enable();
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if(current_thread->cpu == 0)
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timer_irq(regs);
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}
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