Linux kernel mirror (for testing)
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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
21extern void task_cputime(struct task_struct *t,
22 u64 *utime, u64 *stime);
23extern u64 task_gtime(struct task_struct *t);
24#else
25static inline void task_cputime(struct task_struct *t,
26 u64 *utime, u64 *stime)
27{
28 *utime = t->utime;
29 *stime = t->stime;
30}
31
32static inline u64 task_gtime(struct task_struct *t)
33{
34 return t->gtime;
35}
36#endif
37
38#ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
39static 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
47static 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
55extern void task_cputime_adjusted(struct task_struct *p, u64 *ut, u64 *st);
56extern void thread_group_cputime_adjusted(struct task_struct *p, u64 *ut, u64 *st);
57extern 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 */
63void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
64void 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
78static inline
79struct 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
110static inline
111struct 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 */
127static 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 */
148static 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 */
169static 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
180static 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
188extern unsigned long long
189task_sched_runtime(struct task_struct *task);
190
191#endif /* _LINUX_SCHED_CPUTIME_H */