1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _linux_POSIX_TIMERS_H
3 #define _linux_POSIX_TIMERS_H
4
5 #include <linux/spinlock.h>
6 #include <linux/list.h>
7 #include <linux/sched.h>
8 #include <linux/timex.h>
9 #include <linux/alarmtimer.h>
10
11 struct siginfo;
12
13 struct cpu_timer_list {
14 struct list_head entry;
15 u64 expires, incr;
16 struct task_struct *task;
17 int firing;
18 };
19
20 /*
21 * Bit fields within a clockid:
22 *
23 * The most significant 29 bits hold either a pid or a file descriptor.
24 *
25 * Bit 2 indicates whether a cpu clock refers to a thread or a process.
26 *
27 * Bits 1 and 0 give the type: PROF=0, VIRT=1, SCHED=2, or FD=3.
28 *
29 * A clockid is invalid if bits 2, 1, and 0 are all set.
30 */
31 #define CPUCLOCK_PID(clock) ((pid_t) ~((clock) >> 3))
32 #define CPUCLOCK_PERTHREAD(clock) \
33 (((clock) & (clockid_t) CPUCLOCK_PERTHREAD_MASK) != 0)
34
35 #define CPUCLOCK_PERTHREAD_MASK 4
36 #define CPUCLOCK_WHICH(clock) ((clock) & (clockid_t) CPUCLOCK_CLOCK_MASK)
37 #define CPUCLOCK_CLOCK_MASK 3
38 #define CPUCLOCK_PROF 0
39 #define CPUCLOCK_VIRT 1
40 #define CPUCLOCK_SCHED 2
41 #define CPUCLOCK_MAX 3
42 #define CLOCKFD CPUCLOCK_MAX
43 #define CLOCKFD_MASK (CPUCLOCK_PERTHREAD_MASK|CPUCLOCK_CLOCK_MASK)
44
make_process_cpuclock(const unsigned int pid,const clockid_t clock)45 static inline clockid_t make_process_cpuclock(const unsigned int pid,
46 const clockid_t clock)
47 {
48 return ((~pid) << 3) | clock;
49 }
make_thread_cpuclock(const unsigned int tid,const clockid_t clock)50 static inline clockid_t make_thread_cpuclock(const unsigned int tid,
51 const clockid_t clock)
52 {
53 return make_process_cpuclock(tid, clock | CPUCLOCK_PERTHREAD_MASK);
54 }
55
fd_to_clockid(const int fd)56 static inline clockid_t fd_to_clockid(const int fd)
57 {
58 return make_process_cpuclock((unsigned int) fd, CLOCKFD);
59 }
60
clockid_to_fd(const clockid_t clk)61 static inline int clockid_to_fd(const clockid_t clk)
62 {
63 return ~(clk >> 3);
64 }
65
66 #define REQUEUE_PENDING 1
67
68 /**
69 * struct k_itimer - POSIX.1b interval timer structure.
70 * @list: List head for binding the timer to signals->posix_timers
71 * @t_hash: Entry in the posix timer hash table
72 * @it_lock: Lock protecting the timer
73 * @kclock: Pointer to the k_clock struct handling this timer
74 * @it_clock: The posix timer clock id
75 * @it_id: The posix timer id for identifying the timer
76 * @it_active: Marker that timer is active
77 * @it_overrun: The overrun counter for pending signals
78 * @it_overrun_last: The overrun at the time of the last delivered signal
79 * @it_requeue_pending: Indicator that timer waits for being requeued on
80 * signal delivery
81 * @it_sigev_notify: The notify word of sigevent struct for signal delivery
82 * @it_interval: The interval for periodic timers
83 * @it_signal: Pointer to the creators signal struct
84 * @it_pid: The pid of the process/task targeted by the signal
85 * @it_process: The task to wakeup on clock_nanosleep (CPU timers)
86 * @sigq: Pointer to preallocated sigqueue
87 * @it: Union representing the various posix timer type
88 * internals. Also used for rcu freeing the timer.
89 */
90 struct k_itimer {
91 struct list_head list;
92 struct hlist_node t_hash;
93 spinlock_t it_lock;
94 const struct k_clock *kclock;
95 clockid_t it_clock;
96 timer_t it_id;
97 int it_active;
98 s64 it_overrun;
99 s64 it_overrun_last;
100 int it_requeue_pending;
101 int it_sigev_notify;
102 ktime_t it_interval;
103 struct signal_struct *it_signal;
104 union {
105 struct pid *it_pid;
106 struct task_struct *it_process;
107 };
108 struct sigqueue *sigq;
109 union {
110 struct {
111 struct hrtimer timer;
112 } real;
113 struct cpu_timer_list cpu;
114 struct {
115 struct alarm alarmtimer;
116 } alarm;
117 struct rcu_head rcu;
118 } it;
119 };
120
121 void run_posix_cpu_timers(struct task_struct *task);
122 void posix_cpu_timers_exit(struct task_struct *task);
123 void posix_cpu_timers_exit_group(struct task_struct *task);
124 void set_process_cpu_timer(struct task_struct *task, unsigned int clock_idx,
125 u64 *newval, u64 *oldval);
126
127 void update_rlimit_cpu(struct task_struct *task, unsigned long rlim_new);
128
129 void posixtimer_rearm(struct siginfo *info);
130 #endif
131