Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LINUX_SCHED_CPUTIME_H
3#define _LINUX_SCHED_CPUTIME_H
4
5#include <linux/static_call_types.h>
6#include <linux/sched/signal.h>
7
8/*
9 * cputime accounting APIs:
10 */
11
12#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
13extern bool task_cputime(struct task_struct *t,
14 u64 *utime, u64 *stime);
15extern u64 task_gtime(struct task_struct *t);
16#else
17static inline bool task_cputime(struct task_struct *t,
18 u64 *utime, u64 *stime)
19{
20 *utime = t->utime;
21 *stime = t->stime;
22 return false;
23}
24
25static inline u64 task_gtime(struct task_struct *t)
26{
27 return t->gtime;
28}
29#endif
30
31#ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
32static inline void task_cputime_scaled(struct task_struct *t,
33 u64 *utimescaled,
34 u64 *stimescaled)
35{
36 *utimescaled = t->utimescaled;
37 *stimescaled = t->stimescaled;
38}
39#else
40static inline void task_cputime_scaled(struct task_struct *t,
41 u64 *utimescaled,
42 u64 *stimescaled)
43{
44 task_cputime(t, utimescaled, stimescaled);
45}
46#endif
47
48extern void task_cputime_adjusted(struct task_struct *p, u64 *ut, u64 *st);
49extern void thread_group_cputime_adjusted(struct task_struct *p, u64 *ut, u64 *st);
50extern void cputime_adjust(struct task_cputime *curr, struct prev_cputime *prev,
51 u64 *ut, u64 *st);
52
53/*
54 * Thread group CPU time accounting.
55 */
56void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
57void thread_group_sample_cputime(struct task_struct *tsk, u64 *samples);
58
59/*
60 * The following are functions that support scheduler-internal time accounting.
61 * These functions are generally called at the timer tick. None of this depends
62 * on CONFIG_SCHEDSTATS.
63 */
64
65/**
66 * get_running_cputimer - return &tsk->signal->cputimer if cputimers are active
67 *
68 * @tsk: Pointer to target task.
69 */
70#ifdef CONFIG_POSIX_TIMERS
71static inline
72struct thread_group_cputimer *get_running_cputimer(struct task_struct *tsk)
73{
74 struct thread_group_cputimer *cputimer = &tsk->signal->cputimer;
75
76 /*
77 * Check whether posix CPU timers are active. If not the thread
78 * group accounting is not active either. Lockless check.
79 */
80 if (!READ_ONCE(tsk->signal->posix_cputimers.timers_active))
81 return NULL;
82
83 /*
84 * After we flush the task's sum_exec_runtime to sig->sum_sched_runtime
85 * in __exit_signal(), we won't account to the signal struct further
86 * cputime consumed by that task, even though the task can still be
87 * ticking after __exit_signal().
88 *
89 * In order to keep a consistent behaviour between thread group cputime
90 * and thread group cputimer accounting, lets also ignore the cputime
91 * elapsing after __exit_signal() in any thread group timer running.
92 *
93 * This makes sure that POSIX CPU clocks and timers are synchronized, so
94 * that a POSIX CPU timer won't expire while the corresponding POSIX CPU
95 * clock delta is behind the expiring timer value.
96 */
97 if (unlikely(!tsk->sighand))
98 return NULL;
99
100 return cputimer;
101}
102#else
103static inline
104struct thread_group_cputimer *get_running_cputimer(struct task_struct *tsk)
105{
106 return NULL;
107}
108#endif
109
110/**
111 * account_group_user_time - Maintain utime for a thread group.
112 *
113 * @tsk: Pointer to task structure.
114 * @cputime: Time value by which to increment the utime field of the
115 * thread_group_cputime structure.
116 *
117 * If thread group time is being maintained, get the structure for the
118 * running CPU and update the utime field there.
119 */
120static inline void account_group_user_time(struct task_struct *tsk,
121 u64 cputime)
122{
123 struct thread_group_cputimer *cputimer = get_running_cputimer(tsk);
124
125 if (!cputimer)
126 return;
127
128 atomic64_add(cputime, &cputimer->cputime_atomic.utime);
129}
130
131/**
132 * account_group_system_time - Maintain stime for a thread group.
133 *
134 * @tsk: Pointer to task structure.
135 * @cputime: Time value by which to increment the stime field of the
136 * thread_group_cputime structure.
137 *
138 * If thread group time is being maintained, get the structure for the
139 * running CPU and update the stime field there.
140 */
141static inline void account_group_system_time(struct task_struct *tsk,
142 u64 cputime)
143{
144 struct thread_group_cputimer *cputimer = get_running_cputimer(tsk);
145
146 if (!cputimer)
147 return;
148
149 atomic64_add(cputime, &cputimer->cputime_atomic.stime);
150}
151
152/**
153 * account_group_exec_runtime - Maintain exec runtime for a thread group.
154 *
155 * @tsk: Pointer to task structure.
156 * @ns: Time value by which to increment the sum_exec_runtime field
157 * of the thread_group_cputime structure.
158 *
159 * If thread group time is being maintained, get the structure for the
160 * running CPU and update the sum_exec_runtime field there.
161 */
162static inline void account_group_exec_runtime(struct task_struct *tsk,
163 unsigned long long ns)
164{
165 struct thread_group_cputimer *cputimer = get_running_cputimer(tsk);
166
167 if (!cputimer)
168 return;
169
170 atomic64_add(ns, &cputimer->cputime_atomic.sum_exec_runtime);
171}
172
173static inline void prev_cputime_init(struct prev_cputime *prev)
174{
175#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
176 prev->utime = prev->stime = 0;
177 raw_spin_lock_init(&prev->lock);
178#endif
179}
180
181extern unsigned long long
182task_sched_runtime(struct task_struct *task);
183
184#ifdef CONFIG_PARAVIRT
185struct static_key;
186extern struct static_key paravirt_steal_enabled;
187extern struct static_key paravirt_steal_rq_enabled;
188
189#ifdef CONFIG_HAVE_PV_STEAL_CLOCK_GEN
190u64 dummy_steal_clock(int cpu);
191
192DECLARE_STATIC_CALL(pv_steal_clock, dummy_steal_clock);
193
194static inline u64 paravirt_steal_clock(int cpu)
195{
196 return static_call(pv_steal_clock)(cpu);
197}
198#endif
199#endif
200
201#endif /* _LINUX_SCHED_CPUTIME_H */