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 extern void cputime_adjust(struct task_cputime *curr, struct prev_cputime *prev,
58 u64 *ut, u64 *st);
59
60 /*
61 * Thread group CPU time accounting.
62 */
63 void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
64 void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
65
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 cputimer is running
75 *
76 * @tsk: Pointer to target task.
77 */
78 #ifdef CONFIG_POSIX_TIMERS
79 static inline
get_running_cputimer(struct task_struct * tsk)80 struct thread_group_cputimer *get_running_cputimer(struct task_struct *tsk)
81 {
82 struct thread_group_cputimer *cputimer = &tsk->signal->cputimer;
83
84 /* Check if cputimer isn't running. This is accessed without locking. */
85 if (!READ_ONCE(cputimer->running))
86 return NULL;
87
88 /*
89 * After we flush the task's sum_exec_runtime to sig->sum_sched_runtime
90 * in __exit_signal(), we won't account to the signal struct further
91 * cputime consumed by that task, even though the task can still be
92 * ticking after __exit_signal().
93 *
94 * In order to keep a consistent behaviour between thread group cputime
95 * and thread group cputimer accounting, lets also ignore the cputime
96 * elapsing after __exit_signal() in any thread group timer running.
97 *
98 * This makes sure that POSIX CPU clocks and timers are synchronized, so
99 * that a POSIX CPU timer won't expire while the corresponding POSIX CPU
100 * clock delta is behind the expiring timer value.
101 */
102 if (unlikely(!tsk->sighand))
103 return NULL;
104
105 return cputimer;
106 }
107 #else
108 static inline
get_running_cputimer(struct task_struct * tsk)109 struct thread_group_cputimer *get_running_cputimer(struct task_struct *tsk)
110 {
111 return NULL;
112 }
113 #endif
114
115 /**
116 * account_group_user_time - Maintain utime for a thread group.
117 *
118 * @tsk: Pointer to task structure.
119 * @cputime: Time value by which to increment the utime field of the
120 * thread_group_cputime structure.
121 *
122 * If thread group time is being maintained, get the structure for the
123 * running CPU and update the utime field there.
124 */
account_group_user_time(struct task_struct * tsk,u64 cputime)125 static inline void account_group_user_time(struct task_struct *tsk,
126 u64 cputime)
127 {
128 struct thread_group_cputimer *cputimer = get_running_cputimer(tsk);
129
130 if (!cputimer)
131 return;
132
133 atomic64_add(cputime, &cputimer->cputime_atomic.utime);
134 }
135
136 /**
137 * account_group_system_time - Maintain stime for a thread group.
138 *
139 * @tsk: Pointer to task structure.
140 * @cputime: Time value by which to increment the stime field of the
141 * thread_group_cputime structure.
142 *
143 * If thread group time is being maintained, get the structure for the
144 * running CPU and update the stime field there.
145 */
account_group_system_time(struct task_struct * tsk,u64 cputime)146 static inline void account_group_system_time(struct task_struct *tsk,
147 u64 cputime)
148 {
149 struct thread_group_cputimer *cputimer = get_running_cputimer(tsk);
150
151 if (!cputimer)
152 return;
153
154 atomic64_add(cputime, &cputimer->cputime_atomic.stime);
155 }
156
157 /**
158 * account_group_exec_runtime - Maintain exec runtime for a thread group.
159 *
160 * @tsk: Pointer to task structure.
161 * @ns: Time value by which to increment the sum_exec_runtime field
162 * of the thread_group_cputime structure.
163 *
164 * If thread group time is being maintained, get the structure for the
165 * running CPU and update the sum_exec_runtime field there.
166 */
account_group_exec_runtime(struct task_struct * tsk,unsigned long long ns)167 static inline void account_group_exec_runtime(struct task_struct *tsk,
168 unsigned long long ns)
169 {
170 struct thread_group_cputimer *cputimer = get_running_cputimer(tsk);
171
172 if (!cputimer)
173 return;
174
175 atomic64_add(ns, &cputimer->cputime_atomic.sum_exec_runtime);
176 }
177
prev_cputime_init(struct prev_cputime * prev)178 static inline void prev_cputime_init(struct prev_cputime *prev)
179 {
180 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
181 prev->utime = prev->stime = 0;
182 raw_spin_lock_init(&prev->lock);
183 #endif
184 }
185
186 extern unsigned long long
187 task_sched_runtime(struct task_struct *task);
188
189 #endif /* _LINUX_SCHED_CPUTIME_H */
190