1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _LINUX_SCHED_CPUTIME_H 3 #define _LINUX_SCHED_CPUTIME_H 4 5 #include <linux/sched/signal.h> 6 7 /* 8 * cputime accounting APIs: 9 */ 10 11 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 12 #include <asm/cputime.h> 13 14 #ifndef cputime_to_nsecs 15 # define cputime_to_nsecs(__ct) \ 16 (cputime_to_usecs(__ct) * NSEC_PER_USEC) 17 #endif 18 #endif /* CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */ 19 20 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN 21 extern bool task_cputime(struct task_struct *t, 22 u64 *utime, u64 *stime); 23 extern u64 task_gtime(struct task_struct *t); 24 #else 25 static inline bool task_cputime(struct task_struct *t, 26 u64 *utime, u64 *stime) 27 { 28 *utime = t->utime; 29 *stime = t->stime; 30 return false; 31 } 32 33 static inline u64 task_gtime(struct task_struct *t) 34 { 35 return t->gtime; 36 } 37 #endif 38 39 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME 40 static inline void task_cputime_scaled(struct task_struct *t, 41 u64 *utimescaled, 42 u64 *stimescaled) 43 { 44 *utimescaled = t->utimescaled; 45 *stimescaled = t->stimescaled; 46 } 47 #else 48 static inline void task_cputime_scaled(struct task_struct *t, 49 u64 *utimescaled, 50 u64 *stimescaled) 51 { 52 task_cputime(t, utimescaled, stimescaled); 53 } 54 #endif 55 56 extern void task_cputime_adjusted(struct task_struct *p, u64 *ut, u64 *st); 57 extern void thread_group_cputime_adjusted(struct task_struct *p, u64 *ut, u64 *st); 58 extern void cputime_adjust(struct task_cputime *curr, struct prev_cputime *prev, 59 u64 *ut, u64 *st); 60 61 /* 62 * Thread group CPU time accounting. 63 */ 64 void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times); 65 void thread_group_sample_cputime(struct task_struct *tsk, u64 *samples); 66 67 /* 68 * The following are functions that support scheduler-internal time accounting. 69 * These functions are generally called at the timer tick. None of this depends 70 * on CONFIG_SCHEDSTATS. 71 */ 72 73 /** 74 * get_running_cputimer - return &tsk->signal->cputimer if cputimers are active 75 * 76 * @tsk: Pointer to target task. 77 */ 78 #ifdef CONFIG_POSIX_TIMERS 79 static inline 80 struct thread_group_cputimer *get_running_cputimer(struct task_struct *tsk) 81 { 82 struct thread_group_cputimer *cputimer = &tsk->signal->cputimer; 83 84 /* 85 * Check whether posix CPU timers are active. If not the thread 86 * group accounting is not active either. Lockless check. 87 */ 88 if (!READ_ONCE(tsk->signal->posix_cputimers.timers_active)) 89 return NULL; 90 91 /* 92 * After we flush the task's sum_exec_runtime to sig->sum_sched_runtime 93 * in __exit_signal(), we won't account to the signal struct further 94 * cputime consumed by that task, even though the task can still be 95 * ticking after __exit_signal(). 96 * 97 * In order to keep a consistent behaviour between thread group cputime 98 * and thread group cputimer accounting, lets also ignore the cputime 99 * elapsing after __exit_signal() in any thread group timer running. 100 * 101 * This makes sure that POSIX CPU clocks and timers are synchronized, so 102 * that a POSIX CPU timer won't expire while the corresponding POSIX CPU 103 * clock delta is behind the expiring timer value. 104 */ 105 if (unlikely(!tsk->sighand)) 106 return NULL; 107 108 return cputimer; 109 } 110 #else 111 static inline 112 struct thread_group_cputimer *get_running_cputimer(struct task_struct *tsk) 113 { 114 return NULL; 115 } 116 #endif 117 118 /** 119 * account_group_user_time - Maintain utime for a thread group. 120 * 121 * @tsk: Pointer to task structure. 122 * @cputime: Time value by which to increment the utime field of the 123 * thread_group_cputime structure. 124 * 125 * If thread group time is being maintained, get the structure for the 126 * running CPU and update the utime field there. 127 */ 128 static inline void account_group_user_time(struct task_struct *tsk, 129 u64 cputime) 130 { 131 struct thread_group_cputimer *cputimer = get_running_cputimer(tsk); 132 133 if (!cputimer) 134 return; 135 136 atomic64_add(cputime, &cputimer->cputime_atomic.utime); 137 } 138 139 /** 140 * account_group_system_time - Maintain stime for a thread group. 141 * 142 * @tsk: Pointer to task structure. 143 * @cputime: Time value by which to increment the stime field of the 144 * thread_group_cputime structure. 145 * 146 * If thread group time is being maintained, get the structure for the 147 * running CPU and update the stime field there. 148 */ 149 static inline void account_group_system_time(struct task_struct *tsk, 150 u64 cputime) 151 { 152 struct thread_group_cputimer *cputimer = get_running_cputimer(tsk); 153 154 if (!cputimer) 155 return; 156 157 atomic64_add(cputime, &cputimer->cputime_atomic.stime); 158 } 159 160 /** 161 * account_group_exec_runtime - Maintain exec runtime for a thread group. 162 * 163 * @tsk: Pointer to task structure. 164 * @ns: Time value by which to increment the sum_exec_runtime field 165 * of the thread_group_cputime structure. 166 * 167 * If thread group time is being maintained, get the structure for the 168 * running CPU and update the sum_exec_runtime field there. 169 */ 170 static inline void account_group_exec_runtime(struct task_struct *tsk, 171 unsigned long long ns) 172 { 173 struct thread_group_cputimer *cputimer = get_running_cputimer(tsk); 174 175 if (!cputimer) 176 return; 177 178 atomic64_add(ns, &cputimer->cputime_atomic.sum_exec_runtime); 179 } 180 181 static inline void prev_cputime_init(struct prev_cputime *prev) 182 { 183 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 184 prev->utime = prev->stime = 0; 185 raw_spin_lock_init(&prev->lock); 186 #endif 187 } 188 189 extern unsigned long long 190 task_sched_runtime(struct task_struct *task); 191 192 #endif /* _LINUX_SCHED_CPUTIME_H */ 193