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 void task_cputime(struct task_struct *t,
22 u64 *utime, u64 *stime);
23 extern u64 task_gtime(struct task_struct *t);
24 #else
task_cputime(struct task_struct * t,u64 * utime,u64 * stime)25 static inline void task_cputime(struct task_struct *t,
26 u64 *utime, u64 *stime)
27 {
28 *utime = t->utime;
29 *stime = t->stime;
30 }
31
task_gtime(struct task_struct * t)32 static inline u64 task_gtime(struct task_struct *t)
33 {
34 return t->gtime;
35 }
36 #endif
37
38 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
task_cputime_scaled(struct task_struct * t,u64 * utimescaled,u64 * stimescaled)39 static inline void task_cputime_scaled(struct task_struct *t,
40 u64 *utimescaled,
41 u64 *stimescaled)
42 {
43 *utimescaled = t->utimescaled;
44 *stimescaled = t->stimescaled;
45 }
46 #else
task_cputime_scaled(struct task_struct * t,u64 * utimescaled,u64 * stimescaled)47 static inline void task_cputime_scaled(struct task_struct *t,
48 u64 *utimescaled,
49 u64 *stimescaled)
50 {
51 task_cputime(t, utimescaled, stimescaled);
52 }
53 #endif
54
55 extern void task_cputime_adjusted(struct task_struct *p, u64 *ut, u64 *st);
56 extern void thread_group_cputime_adjusted(struct task_struct *p, u64 *ut, u64 *st);
57
58
59 /*
60 * Thread group CPU time accounting.
61 */
62 void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
63 void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
64
65
66 /*
67 * The following are functions that support scheduler-internal time accounting.
68 * These functions are generally called at the timer tick. None of this depends
69 * on CONFIG_SCHEDSTATS.
70 */
71
72 /**
73 * get_running_cputimer - return &tsk->signal->cputimer if cputimer is running
74 *
75 * @tsk: Pointer to target task.
76 */
77 #ifdef CONFIG_POSIX_TIMERS
78 static inline
get_running_cputimer(struct task_struct * tsk)79 struct thread_group_cputimer *get_running_cputimer(struct task_struct *tsk)
80 {
81 struct thread_group_cputimer *cputimer = &tsk->signal->cputimer;
82
83 /* Check if cputimer isn't running. This is accessed without locking. */
84 if (!READ_ONCE(cputimer->running))
85 return NULL;
86
87 /*
88 * After we flush the task's sum_exec_runtime to sig->sum_sched_runtime
89 * in __exit_signal(), we won't account to the signal struct further
90 * cputime consumed by that task, even though the task can still be
91 * ticking after __exit_signal().
92 *
93 * In order to keep a consistent behaviour between thread group cputime
94 * and thread group cputimer accounting, lets also ignore the cputime
95 * elapsing after __exit_signal() in any thread group timer running.
96 *
97 * This makes sure that POSIX CPU clocks and timers are synchronized, so
98 * that a POSIX CPU timer won't expire while the corresponding POSIX CPU
99 * clock delta is behind the expiring timer value.
100 */
101 if (unlikely(!tsk->sighand))
102 return NULL;
103
104 return cputimer;
105 }
106 #else
107 static inline
get_running_cputimer(struct task_struct * tsk)108 struct thread_group_cputimer *get_running_cputimer(struct task_struct *tsk)
109 {
110 return NULL;
111 }
112 #endif
113
114 /**
115 * account_group_user_time - Maintain utime for a thread group.
116 *
117 * @tsk: Pointer to task structure.
118 * @cputime: Time value by which to increment the utime field of the
119 * thread_group_cputime structure.
120 *
121 * If thread group time is being maintained, get the structure for the
122 * running CPU and update the utime field there.
123 */
account_group_user_time(struct task_struct * tsk,u64 cputime)124 static inline void account_group_user_time(struct task_struct *tsk,
125 u64 cputime)
126 {
127 struct thread_group_cputimer *cputimer = get_running_cputimer(tsk);
128
129 if (!cputimer)
130 return;
131
132 atomic64_add(cputime, &cputimer->cputime_atomic.utime);
133 }
134
135 /**
136 * account_group_system_time - Maintain stime for a thread group.
137 *
138 * @tsk: Pointer to task structure.
139 * @cputime: Time value by which to increment the stime field of the
140 * thread_group_cputime structure.
141 *
142 * If thread group time is being maintained, get the structure for the
143 * running CPU and update the stime field there.
144 */
account_group_system_time(struct task_struct * tsk,u64 cputime)145 static inline void account_group_system_time(struct task_struct *tsk,
146 u64 cputime)
147 {
148 struct thread_group_cputimer *cputimer = get_running_cputimer(tsk);
149
150 if (!cputimer)
151 return;
152
153 atomic64_add(cputime, &cputimer->cputime_atomic.stime);
154 }
155
156 /**
157 * account_group_exec_runtime - Maintain exec runtime for a thread group.
158 *
159 * @tsk: Pointer to task structure.
160 * @ns: Time value by which to increment the sum_exec_runtime field
161 * of the thread_group_cputime structure.
162 *
163 * If thread group time is being maintained, get the structure for the
164 * running CPU and update the sum_exec_runtime field there.
165 */
account_group_exec_runtime(struct task_struct * tsk,unsigned long long ns)166 static inline void account_group_exec_runtime(struct task_struct *tsk,
167 unsigned long long ns)
168 {
169 struct thread_group_cputimer *cputimer = get_running_cputimer(tsk);
170
171 if (!cputimer)
172 return;
173
174 atomic64_add(ns, &cputimer->cputime_atomic.sum_exec_runtime);
175 }
176
prev_cputime_init(struct prev_cputime * prev)177 static inline void prev_cputime_init(struct prev_cputime *prev)
178 {
179 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
180 prev->utime = prev->stime = 0;
181 raw_spin_lock_init(&prev->lock);
182 #endif
183 }
184
185 extern unsigned long long
186 task_sched_runtime(struct task_struct *task);
187
188 #endif /* _LINUX_SCHED_CPUTIME_H */
189