/* * linux/kernel/timer.c * * Kernel internal timers, basic process system calls * * Copyright (C) 1991, 1992 Linus Torvalds * * 1997-01-28 Modified by Finn Arne Gangstad to make timers scale better. * * 1997-09-10 Updated NTP code according to technical memorandum Jan '96 * "A Kernel Model for Precision Timekeeping" by Dave Mills * 1998-12-24 Fixed a xtime SMP race (we need the xtime_lock rw spinlock to * serialize accesses to xtime/lost_ticks). * Copyright (C) 1998 Andrea Arcangeli * 1999-03-10 Improved NTP compatibility by Ulrich Windl * 2002-05-31 Move sys_sysinfo here and make its locking sane, Robert Love * 2000-10-05 Implemented scalable SMP per-CPU timer handling. * Copyright (C) 2000, 2001, 2002 Ingo Molnar * Designed by David S. Miller, Alexey Kuznetsov and Ingo Molnar */#include <linux/kernel_stat.h>#include <linux/module.h>#include <linux/interrupt.h>#include <linux/percpu.h>#include <linux/init.h>#include <linux/mm.h>#include <linux/swap.h>#include <linux/pid_namespace.h>#include <linux/notifier.h>#include <linux/thread_info.h>#include <linux/time.h>#include <linux/jiffies.h>#include <linux/posix-timers.h>#include <linux/cpu.h>#include <linux/syscalls.h>#include <linux/delay.h>#include <linux/tick.h>#include <linux/kallsyms.h>#include <asm/uaccess.h>#include <asm/unistd.h>#include <asm/div64.h>#include <asm/timex.h>#include <asm/io.h>
u64 jiffies_64 __cacheline_aligned_in_smp = INITIAL_JIFFIES;EXPORT_SYMBOL(jiffies_64);/* * per-CPU timer vector definitions: */#define TVN_BITS (CONFIG_BASE_SMALL ? 4 : 6)#define TVR_BITS (CONFIG_BASE_SMALL ? 6 : 8)#define TVN_SIZE (1 << TVN_BITS)#define TVR_SIZE (1 << TVR_BITS)#define TVN_MASK (TVN_SIZE - 1)#define TVR_MASK (TVR_SIZE - 1)struct tvec {struct list_head vec[TVN_SIZE];};struct tvec_root {struct list_head vec[TVR_SIZE];};struct tvec_base {
spinlock_t lock;struct timer_list *running_timer;unsigned long timer_jiffies;struct tvec_root tv1;struct tvec tv2;struct tvec tv3;struct tvec tv4;struct tvec tv5;} ____cacheline_aligned;struct tvec_base boot_tvec_bases;EXPORT_SYMBOL(boot_tvec_bases);staticDEFINE_PER_CPU(struct tvec_base *, tvec_bases) = &boot_tvec_bases;/* * Note that all tvec_bases are 2 byte aligned and lower bit of * base in timer_list is guaranteed to be zero. Use the LSB for * the new flag to indicate whether the timer is deferrable */#define TBASE_DEFERRABLE_FLAG (0x1)/* Functions below help us manage 'deferrable' flag */staticinlineunsigned inttbase_get_deferrable(struct tvec_base *base){return((unsigned int)(unsigned long)base & TBASE_DEFERRABLE_FLAG);}staticinlinestruct tvec_base *tbase_get_base(struct tvec_base *base){return((struct tvec_base *)((unsigned long)base & ~TBASE_DEFERRABLE_FLAG));}staticinlinevoidtimer_set_deferrable(struct timer_list
