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