LXR linux/include/linux/posix-timers.h

   1#ifndef _linux_POSIX_TIMERS_H
   2#define _linux_POSIX_TIMERS_H
   3
   4#include <linux/spinlock.h>
   5#include <linux/list.h>
   6#include <linux/sched.h>
   7#include <linux/timex.h>
   8#include <linux/alarmtimer.h>
   9
  10
  11static inline unsigned long long cputime_to_expires(cputime_t expires)
  12{
  13        return (__force unsigned long long)expires;
  14}
  15
  16static inline cputime_t expires_to_cputime(unsigned long long expires)
  17{
  18        return (__force cputime_t)expires;
  19}
  20
  21struct cpu_timer_list {
  22        struct list_head entry;
  23        unsigned long long expires, incr;
  24        struct task_struct *task;
  25        int firing;
  26};
  27
  28/*
  29 * Bit fields within a clockid:
  30 *
  31 * The most significant 29 bits hold either a pid or a file descriptor.
  32 *
  33 * Bit 2 indicates whether a cpu clock refers to a thread or a process.
  34 *
  35 * Bits 1 and 0 give the type: PROF=0, VIRT=1, SCHED=2, or FD=3.
  36 *
  37 * A clockid is invalid if bits 2, 1, and 0 are all set.
  38 */
  39#define CPUCLOCK_PID(clock)             ((pid_t) ~((clock) >> 3))
  40#define CPUCLOCK_PERTHREAD(clock) \
  41        (((clock) & (clockid_t) CPUCLOCK_PERTHREAD_MASK) != 0)
  42
  43#define CPUCLOCK_PERTHREAD_MASK 4
  44#define CPUCLOCK_WHICH(clock)   ((clock) & (clockid_t) CPUCLOCK_CLOCK_MASK)
  45#define CPUCLOCK_CLOCK_MASK     3
  46#define CPUCLOCK_PROF           0
  47#define CPUCLOCK_VIRT           1
  48#define CPUCLOCK_SCHED          2
  49#define CPUCLOCK_MAX            3
  50#define CLOCKFD                 CPUCLOCK_MAX
  51#define CLOCKFD_MASK            (CPUCLOCK_PERTHREAD_MASK|CPUCLOCK_CLOCK_MASK)
  52
  53#define MAKE_PROCESS_CPUCLOCK(pid, clock) \
  54        ((~(clockid_t) (pid) << 3) | (clockid_t) (clock))
  55#define MAKE_THREAD_CPUCLOCK(tid, clock) \
  56        MAKE_PROCESS_CPUCLOCK((tid), (clock) | CPUCLOCK_PERTHREAD_MASK)
  57
  58#define FD_TO_CLOCKID(fd)       ((~(clockid_t) (fd) << 3) | CLOCKFD)
  59#define CLOCKID_TO_FD(clk)      ((unsigned int) ~((clk) >> 3))
  60
  61/* POSIX.1b interval timer structure. */
  62struct k_itimer {
  63        struct list_head list;          /* free/ allocate list */
  64        struct hlist_node t_hash;
  65        spinlock_t it_lock;
  66        clockid_t it_clock;             /* which timer type */
  67        timer_t it_id;                  /* timer id */
  68        int it_overrun;                 /* overrun on pending signal  */
  69        int it_overrun_last;            /* overrun on last delivered signal */
  70        int it_requeue_pending;         /* waiting to requeue this timer */
  71#define REQUEUE_PENDING 1
  72        int it_sigev_notify;            /* notify word of sigevent struct */
  73        struct signal_struct *it_signal;
  74        union {
  75                struct pid *it_pid;     /* pid of process to send signal to */
  76                struct task_struct *it_process; /* for clock_nanosleep */
  77        };
  78        struct sigqueue *sigq;          /* signal queue entry. */
  79        union {
  80                struct {
  81                        struct hrtimer timer;
  82                        ktime_t interval;
  83                } real;
  84                struct cpu_timer_list cpu;
  85                struct {
  86                        unsigned int clock;
  87                        unsigned int node;
  88                        unsigned long incr;
  89                        unsigned long expires;
  90                } mmtimer;
  91                struct {
  92                        struct alarm alarmtimer;
  93                        ktime_t interval;
  94                } alarm;
  95                struct rcu_head rcu;
  96        } it;
  97};
  98
  99struct k_clock {
 100        int (*clock_getres) (const clockid_t which_clock, struct timespec *tp);
 101        int (*clock_set) (const clockid_t which_clock,
 102                          const struct timespec *tp);
 103        int (*clock_get) (const clockid_t which_clock, struct timespec * tp);
 104        int (*clock_adj) (const clockid_t which_clock, struct timex *tx);
 105        int (*timer_create) (struct k_itimer *timer);
 106        int (*nsleep) (const clockid_t which_clock, int flags,
 107                       struct timespec *, struct timespec __user *);
 108        long (*nsleep_restart) (struct restart_block *restart_block);
 109        int (*timer_set) (struct k_itimer * timr, int flags,
 110                          struct itimerspec * new_setting,
 111                          struct itimerspec * old_setting);
 112        int (*timer_del) (struct k_itimer * timr);
 113#define TIMER_RETRY 1
 114        void (*timer_get) (struct k_itimer * timr,
 115                           struct itimerspec * cur_setting);
 116};
 117
 118extern struct k_clock clock_posix_cpu;
 119extern struct k_clock clock_posix_dynamic;
 120
 121void posix_timers_register_clock(const clockid_t clock_id, struct k_clock *new_clock);
 122
 123/* function to call to trigger timer event */
 124int posix_timer_event(struct k_itimer *timr, int si_private);
 125
 126void posix_cpu_timer_schedule(struct k_itimer *timer);
 127
 128void run_posix_cpu_timers(struct task_struct *task);
 129void posix_cpu_timers_exit(struct task_struct *task);
 130void posix_cpu_timers_exit_group(struct task_struct *task);
 131
 132bool posix_cpu_timers_can_stop_tick(struct task_struct *tsk);
 133
 134void set_process_cpu_timer(struct task_struct *task, unsigned int clock_idx,
 135                           cputime_t *newval, cputime_t *oldval);
 136
 137long clock_nanosleep_restart(struct restart_block *restart_block);
 138
 139void update_rlimit_cpu(struct task_struct *task, unsigned long rlim_new);
 140
 141#endif
 142