LXR linux/include/linux/sched/cputime.h

   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_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
  79static inline
  80struct 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
 108static inline
 109struct 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 */
 125static 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 */
 146static 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 */
 167static 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
 178static 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
 186extern unsigned long long
 187task_sched_runtime(struct task_struct *task);
 188
 189#endif /* _LINUX_SCHED_CPUTIME_H */
 190