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 19 static inline clockid_t make_process_cpuclock(const unsigned int pid, 20 const clockid_t clock) 21 { 22 return ((~pid) << 3) | clock; 23 } 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 30 static inline clockid_t fd_to_clockid(const int fd) 31 { 32 return make_process_cpuclock((unsigned int) fd, CLOCKFD); 33 } 34 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 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 71 static inline bool cpu_timer_queued(struct cpu_timer *ctmr) 72 { 73 return !!ctmr->head; 74 } 75 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 86 static inline u64 cpu_timer_getexpires(struct cpu_timer *ctmr) 87 { 88 return ctmr->node.expires; 89 } 90 91 static inline void cpu_timer_setexpires(struct cpu_timer *ctmr, u64 exp) 92 { 93 ctmr->node.expires = exp; 94 } 95 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); 105 106 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 long posixtimer_create_prctl(unsigned long ctrl); 118 119 /* Init task static initializer */ 120 #define INIT_CPU_TIMERBASE(b) { \ 121 .nextevt = U64_MAX, \ 122 } 123 124 #define INIT_CPU_TIMERBASES(b) { \ 125 INIT_CPU_TIMERBASE(b[0]), \ 126 INIT_CPU_TIMERBASE(b[1]), \ 127 INIT_CPU_TIMERBASE(b[2]), \ 128 } 129 130 #define INIT_CPU_TIMERS(s) \ 131 .posix_cputimers = { \ 132 .bases = INIT_CPU_TIMERBASES(s.posix_cputimers.bases), \ 133 }, 134 #else 135 struct cpu_timer { }; 136 #define INIT_CPU_TIMERS(s) 137 static inline void posix_cputimers_init(struct posix_cputimers *pct) { } 138 static inline void posix_cputimers_group_init(struct posix_cputimers *pct, 139 u64 cpu_limit) { } 140 static inline void posixtimer_rearm_itimer(struct task_struct *p) { } 141 static inline bool posixtimer_deliver_signal(struct kernel_siginfo *info, 142 struct sigqueue *timer_sigq) { return false; } 143 static inline void posixtimer_free_timer(struct k_itimer *timer) { } 144 static inline long posixtimer_create_prctl(unsigned long ctrl) { return -EINVAL; } 145 #endif 146 147 #ifdef CONFIG_POSIX_CPU_TIMERS_TASK_WORK 148 void clear_posix_cputimers_work(struct task_struct *p); 149 void posix_cputimers_init_work(void); 150 #else 151 static inline void clear_posix_cputimers_work(struct task_struct *p) { } 152 static inline void posix_cputimers_init_work(void) { } 153 #endif 154 155 /** 156 * struct k_itimer - POSIX.1b interval timer structure. 157 * @list: List node for binding the timer to tsk::signal::posix_timers 158 * @ignored_list: List node for tracking ignored timers in tsk::signal::ignored_posix_timers 159 * @t_hash: Entry in the posix timer hash table 160 * @it_lock: Lock protecting the timer 161 * @kclock: Pointer to the k_clock struct handling this timer 162 * @it_clock: The posix timer clock id 163 * @it_id: The posix timer id for identifying the timer 164 * @it_status: The status of the timer 165 * @it_sig_periodic: The periodic status at signal delivery 166 * @it_overrun: The overrun counter for pending signals 167 * @it_overrun_last: The overrun at the time of the last delivered signal 168 * @it_signal_seq: Sequence count to control signal delivery 169 * @it_sigqueue_seq: The sequence count at the point where the signal was queued 170 * @it_sigev_notify: The notify word of sigevent struct for signal delivery 171 * @it_interval: The interval for periodic timers 172 * @it_signal: Pointer to the creators signal struct 173 * @it_pid: The pid of the process/task targeted by the signal 174 * @it_process: The task to wakeup on clock_nanosleep (CPU timers) 175 * @rcuref: Reference count for life time management 176 * @sigq: Embedded sigqueue 177 * @it: Union representing the various posix timer type 178 * internals. 179 * @rcu: RCU head for freeing the timer. 180 */ 181 struct k_itimer { 182 /* 1st cacheline contains read-mostly fields */ 183 struct hlist_node t_hash; 184 struct hlist_node list; 185 timer_t it_id; 186 clockid_t it_clock; 187 int it_sigev_notify; 188 enum pid_type it_pid_type; 189 struct signal_struct *it_signal; 190 const struct k_clock *kclock; 191 192 /* 2nd cacheline and above contain fields which are modified regularly */ 193 spinlock_t it_lock; 194 int it_status; 195 bool it_sig_periodic; 196 s64 it_overrun; 197 s64 it_overrun_last; 198 unsigned int it_signal_seq; 199 unsigned int it_sigqueue_seq; 200 ktime_t it_interval; 201 struct hlist_node ignored_list; 202 union { 203 struct pid *it_pid; 204 struct task_struct *it_process; 205 }; 206 struct sigqueue sigq; 207 rcuref_t rcuref; 208 union { 209 struct { 210 struct hrtimer timer; 211 } real; 212 struct cpu_timer cpu; 213 struct { 214 struct alarm alarmtimer; 215 } alarm; 216 } it; 217 struct rcu_head rcu; 218 } ____cacheline_aligned_in_smp; 219 220 void run_posix_cpu_timers(void); 221 void posix_cpu_timers_exit(struct task_struct *task); 222 void posix_cpu_timers_exit_group(struct task_struct *task); 223 void set_process_cpu_timer(struct task_struct *task, unsigned int clock_idx, 224 u64 *newval, u64 *oldval); 225 226 int update_rlimit_cpu(struct task_struct *task, unsigned long rlim_new); 227 228 #ifdef CONFIG_POSIX_TIMERS 229 static inline void posixtimer_putref(struct k_itimer *tmr) 230 { 231 if (rcuref_put(&tmr->rcuref)) 232 posixtimer_free_timer(tmr); 233 } 234 235 static inline void posixtimer_sigqueue_getref(struct sigqueue *q) 236 { 237 struct k_itimer *tmr = container_of(q, struct k_itimer, sigq); 238 239 WARN_ON_ONCE(!rcuref_get(&tmr->rcuref)); 240 } 241 242 static inline void posixtimer_sigqueue_putref(struct sigqueue *q) 243 { 244 struct k_itimer *tmr = container_of(q, struct k_itimer, sigq); 245 246 posixtimer_putref(tmr); 247 } 248 249 static inline bool posixtimer_valid(const struct k_itimer *timer) 250 { 251 unsigned long val = (unsigned long)timer->it_signal; 252 253 return !(val & 0x1UL); 254 } 255 #else /* CONFIG_POSIX_TIMERS */ 256 static inline void posixtimer_sigqueue_getref(struct sigqueue *q) { } 257 static inline void posixtimer_sigqueue_putref(struct sigqueue *q) { } 258 #endif /* !CONFIG_POSIX_TIMERS */ 259 260 #endif 261