Line data    Source code

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