1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _linux_POSIX_TIMERS_H
3 #define _linux_POSIX_TIMERS_H
4
5 #include <linux/alarmtimer.h>
6 #include <linux/list.h>
7 #include <linux/mutex.h>
8 #include <linux/pid.h>
9 #include <linux/posix-timers_types.h>
10 #include <linux/rcuref.h>
11 #include <linux/spinlock.h>
12 #include <linux/timerqueue.h>
13
14 struct kernel_siginfo;
15 struct task_struct;
16 struct sigqueue;
17 struct k_itimer;
18
make_process_cpuclock(const unsigned int pid,const clockid_t clock)19 static inline clockid_t make_process_cpuclock(const unsigned int pid,
20 const clockid_t clock)
21 {
22 return ((~pid) << 3) | clock;
23 }
make_thread_cpuclock(const unsigned int tid,const clockid_t clock)24 static inline clockid_t make_thread_cpuclock(const unsigned int tid,
25 const clockid_t clock)
26 {
27 return make_process_cpuclock(tid, clock | CPUCLOCK_PERTHREAD_MASK);
28 }
29
fd_to_clockid(const int fd)30 static inline clockid_t fd_to_clockid(const int fd)
31 {
32 return make_process_cpuclock((unsigned int) fd, CLOCKFD);
33 }
34
clockid_to_fd(const clockid_t clk)35 static inline int clockid_to_fd(const clockid_t clk)
36 {
37 return ~(clk >> 3);
38 }
39
40 #ifdef CONFIG_POSIX_TIMERS
41
42 #include <linux/signal_types.h>
43
44 /**
45 * cpu_timer - Posix CPU timer representation for k_itimer
46 * @node: timerqueue node to queue in the task/sig
47 * @head: timerqueue head on which this timer is queued
48 * @pid: Pointer to target task PID
49 * @elist: List head for the expiry list
50 * @firing: Timer is currently firing
51 * @nanosleep: Timer is used for nanosleep and is not a regular posix-timer
52 * @handling: Pointer to the task which handles expiry
53 */
54 struct cpu_timer {
55 struct timerqueue_node node;
56 struct timerqueue_head *head;
57 struct pid *pid;
58 struct list_head elist;
59 bool firing;
60 bool nanosleep;
61 struct task_struct __rcu *handling;
62 };
63
cpu_timer_enqueue(struct timerqueue_head * head,struct cpu_timer * ctmr)64 static inline bool cpu_timer_enqueue(struct timerqueue_head *head,
65 struct cpu_timer *ctmr)
66 {
67 ctmr->head = head;
68 return timerqueue_add(head, &ctmr->node);
69 }
70
cpu_timer_queued(struct cpu_timer * ctmr)71 static inline bool cpu_timer_queued(struct cpu_timer *ctmr)
72 {
73 return !!ctmr->head;
74 }
75
cpu_timer_dequeue(struct cpu_timer * ctmr)76 static inline bool cpu_timer_dequeue(struct cpu_timer *ctmr)
77 {
78 if (cpu_timer_queued(ctmr)) {
79 timerqueue_del(ctmr->head, &ctmr->node);
80 ctmr->head = NULL;
81 return true;
82 }
83 return false;
84 }
85
cpu_timer_getexpires(struct cpu_timer * ctmr)86 static inline u64 cpu_timer_getexpires(struct cpu_timer *ctmr)
87 {
88 return ctmr->node.expires;
89 }
90
cpu_timer_setexpires(struct cpu_timer * ctmr,u64 exp)91 static inline void cpu_timer_setexpires(struct cpu_timer *ctmr, u64 exp)
92 {
93 ctmr->node.expires = exp;
94 }
95
posix_cputimers_init(struct posix_cputimers * pct)96 static inline void posix_cputimers_init(struct posix_cputimers *pct)
97 {
98 memset(pct, 0, sizeof(*pct));
99 pct->bases[0].nextevt = U64_MAX;
100 pct->bases[1].nextevt = U64_MAX;
101 pct->bases[2].nextevt = U64_MAX;
102 }
103
104 void posix_cputimers_group_init(struct posix_cputimers *pct, u64 cpu_limit);
105
posix_cputimers_rt_watchdog(struct posix_cputimers * pct,u64 runtime)106 static inline void posix_cputimers_rt_watchdog(struct posix_cputimers *pct,
107 u64 runtime)
108 {
109 pct->bases[CPUCLOCK_SCHED].nextevt = runtime;
110 }
111
112 void posixtimer_rearm_itimer(struct task_struct *p);
113 bool posixtimer_init_sigqueue(struct sigqueue *q);
114 void posixtimer_send_sigqueue(struct k_itimer *tmr);
115 bool posixtimer_deliver_signal(struct kernel_siginfo *info, struct sigqueue *timer_sigq);
116 void posixtimer_free_timer(struct k_itimer *timer);
117
118 /* Init task static initializer */
119 #define INIT_CPU_TIMERBASE(b) { \
120 .nextevt = U64_MAX, \
121 }
122
123 #define INIT_CPU_TIMERBASES(b) { \
124 INIT_CPU_TIMERBASE(b[0]), \
125 INIT_CPU_TIMERBASE(b[1]), \
126 INIT_CPU_TIMERBASE(b[2]), \
127 }
128
129 #define INIT_CPU_TIMERS(s) \
130 .posix_cputimers = { \
131 .bases = INIT_CPU_TIMERBASES(s.posix_cputimers.bases), \
132 },
133 #else
134 struct cpu_timer { };
135 #define INIT_CPU_TIMERS(s)
posix_cputimers_init(struct posix_cputimers * pct)136 static inline void posix_cputimers_init(struct posix_cputimers *pct) { }
posix_cputimers_group_init(struct posix_cputimers * pct,u64 cpu_limit)137 static inline void posix_cputimers_group_init(struct posix_cputimers *pct,
138 u64 cpu_limit) { }
posixtimer_rearm_itimer(struct task_struct * p)139 static inline void posixtimer_rearm_itimer(struct task_struct *p) { }
posixtimer_deliver_signal(struct kernel_siginfo * info,struct sigqueue * timer_sigq)140 static inline bool posixtimer_deliver_signal(struct kernel_siginfo *info,
141 struct sigqueue *timer_sigq) { return false; }
posixtimer_free_timer(struct k_itimer * timer)142 static inline void posixtimer_free_timer(struct k_itimer *timer) { }
143 #endif
144
145 #ifdef CONFIG_POSIX_CPU_TIMERS_TASK_WORK
146 void clear_posix_cputimers_work(struct task_struct *p);
147 void posix_cputimers_init_work(void);
148 #else
clear_posix_cputimers_work(struct task_struct * p)149 static inline void clear_posix_cputimers_work(struct task_struct *p) { }
posix_cputimers_init_work(void)150 static inline void posix_cputimers_init_work(void) { }
151 #endif
152
153 /**
154 * struct k_itimer - POSIX.1b interval timer structure.
155 * @list: List node for binding the timer to tsk::signal::posix_timers
156 * @ignored_list: List node for tracking ignored timers in tsk::signal::ignored_posix_timers
157 * @t_hash: Entry in the posix timer hash table
158 * @it_lock: Lock protecting the timer
159 * @kclock: Pointer to the k_clock struct handling this timer
160 * @it_clock: The posix timer clock id
161 * @it_id: The posix timer id for identifying the timer
162 * @it_status: The status of the timer
163 * @it_sig_periodic: The periodic status at signal delivery
164 * @it_overrun: The overrun counter for pending signals
165 * @it_overrun_last: The overrun at the time of the last delivered signal
166 * @it_signal_seq: Sequence count to control signal delivery
167 * @it_sigqueue_seq: The sequence count at the point where the signal was queued
168 * @it_sigev_notify: The notify word of sigevent struct for signal delivery
169 * @it_interval: The interval for periodic timers
170 * @it_signal: Pointer to the creators signal struct
171 * @it_pid: The pid of the process/task targeted by the signal
172 * @it_process: The task to wakeup on clock_nanosleep (CPU timers)
173 * @rcuref: Reference count for life time management
174 * @sigq: Embedded sigqueue
175 * @it: Union representing the various posix timer type
176 * internals.
177 * @rcu: RCU head for freeing the timer.
178 */
179 struct k_itimer {
180 struct hlist_node list;
181 struct hlist_node ignored_list;
182 struct hlist_node t_hash;
183 spinlock_t it_lock;
184 const struct k_clock *kclock;
185 clockid_t it_clock;
186 timer_t it_id;
187 int it_status;
188 bool it_sig_periodic;
189 s64 it_overrun;
190 s64 it_overrun_last;
191 unsigned int it_signal_seq;
192 unsigned int it_sigqueue_seq;
193 int it_sigev_notify;
194 enum pid_type it_pid_type;
195 ktime_t it_interval;
196 struct signal_struct *it_signal;
197 union {
198 struct pid *it_pid;
199 struct task_struct *it_process;
200 };
201 struct sigqueue sigq;
202 rcuref_t rcuref;
203 union {
204 struct {
205 struct hrtimer timer;
206 } real;
207 struct cpu_timer cpu;
208 struct {
209 struct alarm alarmtimer;
210 } alarm;
211 } it;
212 struct rcu_head rcu;
213 };
214
215 void run_posix_cpu_timers(void);
216 void posix_cpu_timers_exit(struct task_struct *task);
217 void posix_cpu_timers_exit_group(struct task_struct *task);
218 void set_process_cpu_timer(struct task_struct *task, unsigned int clock_idx,
219 u64 *newval, u64 *oldval);
220
221 int update_rlimit_cpu(struct task_struct *task, unsigned long rlim_new);
222
223 #ifdef CONFIG_POSIX_TIMERS
posixtimer_putref(struct k_itimer * tmr)224 static inline void posixtimer_putref(struct k_itimer *tmr)
225 {
226 if (rcuref_put(&tmr->rcuref))
227 posixtimer_free_timer(tmr);
228 }
229
posixtimer_sigqueue_getref(struct sigqueue * q)230 static inline void posixtimer_sigqueue_getref(struct sigqueue *q)
231 {
232 struct k_itimer *tmr = container_of(q, struct k_itimer, sigq);
233
234 WARN_ON_ONCE(!rcuref_get(&tmr->rcuref));
235 }
236
posixtimer_sigqueue_putref(struct sigqueue * q)237 static inline void posixtimer_sigqueue_putref(struct sigqueue *q)
238 {
239 struct k_itimer *tmr = container_of(q, struct k_itimer, sigq);
240
241 posixtimer_putref(tmr);
242 }
243 #else /* CONFIG_POSIX_TIMERS */
posixtimer_sigqueue_getref(struct sigqueue * q)244 static inline void posixtimer_sigqueue_getref(struct sigqueue *q) { }
posixtimer_sigqueue_putref(struct sigqueue * q)245 static inline void posixtimer_sigqueue_putref(struct sigqueue *q) { }
246 #endif /* !CONFIG_POSIX_TIMERS */
247
248 #endif
249