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_sample_cputime(struct task_struct *tsk, u64 *samples);
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 cputimers are active
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 /*
84 * Check whether posix CPU timers are active. If not the thread
85 * group accounting is not active either. Lockless check.
86 */
87 if (!READ_ONCE(tsk->signal->posix_cputimers.timers_active))
88 return NULL;
89
90 /*
91 * After we flush the task's sum_exec_runtime to sig->sum_sched_runtime
92 * in __exit_signal(), we won't account to the signal struct further
93 * cputime consumed by that task, even though the task can still be
94 * ticking after __exit_signal().
95 *
96 * In order to keep a consistent behaviour between thread group cputime
97 * and thread group cputimer accounting, lets also ignore the cputime
98 * elapsing after __exit_signal() in any thread group timer running.
99 *
100 * This makes sure that POSIX CPU clocks and timers are synchronized, so
101 * that a POSIX CPU timer won't expire while the corresponding POSIX CPU
102 * clock delta is behind the expiring timer value.
103 */
104 if (unlikely(!tsk->sighand))
105 return NULL;
106
107 return cputimer;
108 }
109 #else
110 static inline
get_running_cputimer(struct task_struct * tsk)111 struct thread_group_cputimer *get_running_cputimer(struct task_struct *tsk)
112 {
113 return NULL;
114 }
115 #endif
116
117 /**
118 * account_group_user_time - Maintain utime for a thread group.
119 *
120 * @tsk: Pointer to task structure.
121 * @cputime: Time value by which to increment the utime field of the
122 * thread_group_cputime structure.
123 *
124 * If thread group time is being maintained, get the structure for the
125 * running CPU and update the utime field there.
126 */
account_group_user_time(struct task_struct * tsk,u64 cputime)127 static inline void account_group_user_time(struct task_struct *tsk,
128 u64 cputime)
129 {
130 struct thread_group_cputimer *cputimer = get_running_cputimer(tsk);
131
132 if (!cputimer)
133 return;
134
135 atomic64_add(cputime, &cputimer->cputime_atomic.utime);
136 }
137
138 /**
139 * account_group_system_time - Maintain stime for a thread group.
140 *
141 * @tsk: Pointer to task structure.
142 * @cputime: Time value by which to increment the stime field of the
143 * thread_group_cputime structure.
144 *
145 * If thread group time is being maintained, get the structure for the
146 * running CPU and update the stime field there.
147 */
account_group_system_time(struct task_struct * tsk,u64 cputime)148 static inline void account_group_system_time(struct task_struct *tsk,
149 u64 cputime)
150 {
151 struct thread_group_cputimer *cputimer = get_running_cputimer(tsk);
152
153 if (!cputimer)
154 return;
155
156 atomic64_add(cputime, &cputimer->cputime_atomic.stime);
157 }
158
159 /**
160 * account_group_exec_runtime - Maintain exec runtime for a thread group.
161 *
162 * @tsk: Pointer to task structure.
163 * @ns: Time value by which to increment the sum_exec_runtime field
164 * of the thread_group_cputime structure.
165 *
166 * If thread group time is being maintained, get the structure for the
167 * running CPU and update the sum_exec_runtime field there.
168 */
account_group_exec_runtime(struct task_struct * tsk,unsigned long long ns)169 static inline void account_group_exec_runtime(struct task_struct *tsk,
170 unsigned long long ns)
171 {
172 struct thread_group_cputimer *cputimer = get_running_cputimer(tsk);
173
174 if (!cputimer)
175 return;
176
177 atomic64_add(ns, &cputimer->cputime_atomic.sum_exec_runtime);
178 }
179
prev_cputime_init(struct prev_cputime * prev)180 static inline void prev_cputime_init(struct prev_cputime *prev)
181 {
182 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
183 prev->utime = prev->stime = 0;
184 raw_spin_lock_init(&prev->lock);
185 #endif
186 }
187
188 extern unsigned long long
189 task_sched_runtime(struct task_struct *task);
190
191 #endif /* _LINUX_SCHED_CPUTIME_H */
192