Loading...
1
2#ifdef CONFIG_SCHEDSTATS
3
4/*
5 * Expects runqueue lock to be held for atomicity of update
6 */
7static inline void
8rq_sched_info_arrive(struct rq *rq, unsigned long long delta)
9{
10 if (rq) {
11 rq->rq_sched_info.run_delay += delta;
12 rq->rq_sched_info.pcount++;
13 }
14}
15
16/*
17 * Expects runqueue lock to be held for atomicity of update
18 */
19static inline void
20rq_sched_info_depart(struct rq *rq, unsigned long long delta)
21{
22 if (rq)
23 rq->rq_cpu_time += delta;
24}
25
26static inline void
27rq_sched_info_dequeued(struct rq *rq, unsigned long long delta)
28{
29 if (rq)
30 rq->rq_sched_info.run_delay += delta;
31}
32# define schedstat_inc(rq, field) do { (rq)->field++; } while (0)
33# define schedstat_add(rq, field, amt) do { (rq)->field += (amt); } while (0)
34# define schedstat_set(var, val) do { var = (val); } while (0)
35#else /* !CONFIG_SCHEDSTATS */
36static inline void
37rq_sched_info_arrive(struct rq *rq, unsigned long long delta)
38{}
39static inline void
40rq_sched_info_dequeued(struct rq *rq, unsigned long long delta)
41{}
42static inline void
43rq_sched_info_depart(struct rq *rq, unsigned long long delta)
44{}
45# define schedstat_inc(rq, field) do { } while (0)
46# define schedstat_add(rq, field, amt) do { } while (0)
47# define schedstat_set(var, val) do { } while (0)
48#endif
49
50#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
51static inline void sched_info_reset_dequeued(struct task_struct *t)
52{
53 t->sched_info.last_queued = 0;
54}
55
56/*
57 * We are interested in knowing how long it was from the *first* time a
58 * task was queued to the time that it finally hit a cpu, we call this routine
59 * from dequeue_task() to account for possible rq->clock skew across cpus. The
60 * delta taken on each cpu would annul the skew.
61 */
62static inline void sched_info_dequeued(struct rq *rq, struct task_struct *t)
63{
64 unsigned long long now = rq_clock(rq), delta = 0;
65
66 if (unlikely(sched_info_on()))
67 if (t->sched_info.last_queued)
68 delta = now - t->sched_info.last_queued;
69 sched_info_reset_dequeued(t);
70 t->sched_info.run_delay += delta;
71
72 rq_sched_info_dequeued(rq, delta);
73}
74
75/*
76 * Called when a task finally hits the cpu. We can now calculate how
77 * long it was waiting to run. We also note when it began so that we
78 * can keep stats on how long its timeslice is.
79 */
80static void sched_info_arrive(struct rq *rq, struct task_struct *t)
81{
82 unsigned long long now = rq_clock(rq), delta = 0;
83
84 if (t->sched_info.last_queued)
85 delta = now - t->sched_info.last_queued;
86 sched_info_reset_dequeued(t);
87 t->sched_info.run_delay += delta;
88 t->sched_info.last_arrival = now;
89 t->sched_info.pcount++;
90
91 rq_sched_info_arrive(rq, delta);
92}
93
94/*
95 * This function is only called from enqueue_task(), but also only updates
96 * the timestamp if it is already not set. It's assumed that
97 * sched_info_dequeued() will clear that stamp when appropriate.
98 */
99static inline void sched_info_queued(struct rq *rq, struct task_struct *t)
100{
101 if (unlikely(sched_info_on()))
102 if (!t->sched_info.last_queued)
103 t->sched_info.last_queued = rq_clock(rq);
104}
105
106/*
107 * Called when a process ceases being the active-running process involuntarily
108 * due, typically, to expiring its time slice (this may also be called when
109 * switching to the idle task). Now we can calculate how long we ran.
110 * Also, if the process is still in the TASK_RUNNING state, call
111 * sched_info_queued() to mark that it has now again started waiting on
112 * the runqueue.
113 */
114static inline void sched_info_depart(struct rq *rq, struct task_struct *t)
115{
116 unsigned long long delta = rq_clock(rq) -
117 t->sched_info.last_arrival;
118
119 rq_sched_info_depart(rq, delta);
120
121 if (t->state == TASK_RUNNING)
122 sched_info_queued(rq, t);
123}
124
125/*
126 * Called when tasks are switched involuntarily due, typically, to expiring
127 * their time slice. (This may also be called when switching to or from
128 * the idle task.) We are only called when prev != next.
129 */
130static inline void
131__sched_info_switch(struct rq *rq,
132 struct task_struct *prev, struct task_struct *next)
133{
134 /*
135 * prev now departs the cpu. It's not interesting to record
136 * stats about how efficient we were at scheduling the idle
137 * process, however.
138 */
139 if (prev != rq->idle)
140 sched_info_depart(rq, prev);
141
142 if (next != rq->idle)
143 sched_info_arrive(rq, next);
144}
145static inline void
146sched_info_switch(struct rq *rq,
147 struct task_struct *prev, struct task_struct *next)
148{
149 if (unlikely(sched_info_on()))
150 __sched_info_switch(rq, prev, next);
151}
152#else
153#define sched_info_queued(rq, t) do { } while (0)
154#define sched_info_reset_dequeued(t) do { } while (0)
155#define sched_info_dequeued(rq, t) do { } while (0)
156#define sched_info_depart(rq, t) do { } while (0)
157#define sched_info_arrive(rq, next) do { } while (0)
158#define sched_info_switch(rq, t, next) do { } while (0)
159#endif /* CONFIG_SCHEDSTATS || CONFIG_TASK_DELAY_ACCT */
160
161/*
162 * The following are functions that support scheduler-internal time accounting.
163 * These functions are generally called at the timer tick. None of this depends
164 * on CONFIG_SCHEDSTATS.
165 */
166
167/**
168 * cputimer_running - return true if cputimer is running
169 *
170 * @tsk: Pointer to target task.
171 */
172static inline bool cputimer_running(struct task_struct *tsk)
173
174{
175 struct thread_group_cputimer *cputimer = &tsk->signal->cputimer;
176
177 if (!cputimer->running)
178 return false;
179
180 /*
181 * After we flush the task's sum_exec_runtime to sig->sum_sched_runtime
182 * in __exit_signal(), we won't account to the signal struct further
183 * cputime consumed by that task, even though the task can still be
184 * ticking after __exit_signal().
185 *
186 * In order to keep a consistent behaviour between thread group cputime
187 * and thread group cputimer accounting, lets also ignore the cputime
188 * elapsing after __exit_signal() in any thread group timer running.
189 *
190 * This makes sure that POSIX CPU clocks and timers are synchronized, so
191 * that a POSIX CPU timer won't expire while the corresponding POSIX CPU
192 * clock delta is behind the expiring timer value.
193 */
194 if (unlikely(!tsk->sighand))
195 return false;
196
197 return true;
198}
199
200/**
201 * account_group_user_time - Maintain utime for a thread group.
202 *
203 * @tsk: Pointer to task structure.
204 * @cputime: Time value by which to increment the utime field of the
205 * thread_group_cputime structure.
206 *
207 * If thread group time is being maintained, get the structure for the
208 * running CPU and update the utime field there.
209 */
210static inline void account_group_user_time(struct task_struct *tsk,
211 cputime_t cputime)
212{
213 struct thread_group_cputimer *cputimer = &tsk->signal->cputimer;
214
215 if (!cputimer_running(tsk))
216 return;
217
218 raw_spin_lock(&cputimer->lock);
219 cputimer->cputime.utime += cputime;
220 raw_spin_unlock(&cputimer->lock);
221}
222
223/**
224 * account_group_system_time - Maintain stime for a thread group.
225 *
226 * @tsk: Pointer to task structure.
227 * @cputime: Time value by which to increment the stime field of the
228 * thread_group_cputime structure.
229 *
230 * If thread group time is being maintained, get the structure for the
231 * running CPU and update the stime field there.
232 */
233static inline void account_group_system_time(struct task_struct *tsk,
234 cputime_t cputime)
235{
236 struct thread_group_cputimer *cputimer = &tsk->signal->cputimer;
237
238 if (!cputimer_running(tsk))
239 return;
240
241 raw_spin_lock(&cputimer->lock);
242 cputimer->cputime.stime += cputime;
243 raw_spin_unlock(&cputimer->lock);
244}
245
246/**
247 * account_group_exec_runtime - Maintain exec runtime for a thread group.
248 *
249 * @tsk: Pointer to task structure.
250 * @ns: Time value by which to increment the sum_exec_runtime field
251 * of the thread_group_cputime structure.
252 *
253 * If thread group time is being maintained, get the structure for the
254 * running CPU and update the sum_exec_runtime field there.
255 */
256static inline void account_group_exec_runtime(struct task_struct *tsk,
257 unsigned long long ns)
258{
259 struct thread_group_cputimer *cputimer = &tsk->signal->cputimer;
260
261 if (!cputimer_running(tsk))
262 return;
263
264 raw_spin_lock(&cputimer->lock);
265 cputimer->cputime.sum_exec_runtime += ns;
266 raw_spin_unlock(&cputimer->lock);
267}
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _KERNEL_STATS_H
3#define _KERNEL_STATS_H
4
5#ifdef CONFIG_SCHEDSTATS
6
7extern struct static_key_false sched_schedstats;
8
9/*
10 * Expects runqueue lock to be held for atomicity of update
11 */
12static inline void
13rq_sched_info_arrive(struct rq *rq, unsigned long long delta)
14{
15 if (rq) {
16 rq->rq_sched_info.run_delay += delta;
17 rq->rq_sched_info.pcount++;
18 }
19}
20
21/*
22 * Expects runqueue lock to be held for atomicity of update
23 */
24static inline void
25rq_sched_info_depart(struct rq *rq, unsigned long long delta)
26{
27 if (rq)
28 rq->rq_cpu_time += delta;
29}
30
31static inline void
32rq_sched_info_dequeue(struct rq *rq, unsigned long long delta)
33{
34 if (rq)
35 rq->rq_sched_info.run_delay += delta;
36}
37#define schedstat_enabled() static_branch_unlikely(&sched_schedstats)
38#define __schedstat_inc(var) do { var++; } while (0)
39#define schedstat_inc(var) do { if (schedstat_enabled()) { var++; } } while (0)
40#define __schedstat_add(var, amt) do { var += (amt); } while (0)
41#define schedstat_add(var, amt) do { if (schedstat_enabled()) { var += (amt); } } while (0)
42#define __schedstat_set(var, val) do { var = (val); } while (0)
43#define schedstat_set(var, val) do { if (schedstat_enabled()) { var = (val); } } while (0)
44#define schedstat_val(var) (var)
45#define schedstat_val_or_zero(var) ((schedstat_enabled()) ? (var) : 0)
46
47void __update_stats_wait_start(struct rq *rq, struct task_struct *p,
48 struct sched_statistics *stats);
49
50void __update_stats_wait_end(struct rq *rq, struct task_struct *p,
51 struct sched_statistics *stats);
52void __update_stats_enqueue_sleeper(struct rq *rq, struct task_struct *p,
53 struct sched_statistics *stats);
54
55static inline void
56check_schedstat_required(void)
57{
58 if (schedstat_enabled())
59 return;
60
61 /* Force schedstat enabled if a dependent tracepoint is active */
62 if (trace_sched_stat_wait_enabled() ||
63 trace_sched_stat_sleep_enabled() ||
64 trace_sched_stat_iowait_enabled() ||
65 trace_sched_stat_blocked_enabled() ||
66 trace_sched_stat_runtime_enabled())
67 printk_deferred_once("Scheduler tracepoints stat_sleep, stat_iowait, stat_blocked and stat_runtime require the kernel parameter schedstats=enable or kernel.sched_schedstats=1\n");
68}
69
70#else /* !CONFIG_SCHEDSTATS: */
71
72static inline void rq_sched_info_arrive (struct rq *rq, unsigned long long delta) { }
73static inline void rq_sched_info_dequeue(struct rq *rq, unsigned long long delta) { }
74static inline void rq_sched_info_depart (struct rq *rq, unsigned long long delta) { }
75# define schedstat_enabled() 0
76# define __schedstat_inc(var) do { } while (0)
77# define schedstat_inc(var) do { } while (0)
78# define __schedstat_add(var, amt) do { } while (0)
79# define schedstat_add(var, amt) do { } while (0)
80# define __schedstat_set(var, val) do { } while (0)
81# define schedstat_set(var, val) do { } while (0)
82# define schedstat_val(var) 0
83# define schedstat_val_or_zero(var) 0
84
85# define __update_stats_wait_start(rq, p, stats) do { } while (0)
86# define __update_stats_wait_end(rq, p, stats) do { } while (0)
87# define __update_stats_enqueue_sleeper(rq, p, stats) do { } while (0)
88# define check_schedstat_required() do { } while (0)
89
90#endif /* CONFIG_SCHEDSTATS */
91
92#ifdef CONFIG_FAIR_GROUP_SCHED
93struct sched_entity_stats {
94 struct sched_entity se;
95 struct sched_statistics stats;
96} __no_randomize_layout;
97#endif
98
99static inline struct sched_statistics *
100__schedstats_from_se(struct sched_entity *se)
101{
102#ifdef CONFIG_FAIR_GROUP_SCHED
103 if (!entity_is_task(se))
104 return &container_of(se, struct sched_entity_stats, se)->stats;
105#endif
106 return &task_of(se)->stats;
107}
108
109#ifdef CONFIG_PSI
110void psi_task_change(struct task_struct *task, int clear, int set);
111void psi_task_switch(struct task_struct *prev, struct task_struct *next,
112 bool sleep);
113void psi_account_irqtime(struct task_struct *task, u32 delta);
114
115/*
116 * PSI tracks state that persists across sleeps, such as iowaits and
117 * memory stalls. As a result, it has to distinguish between sleeps,
118 * where a task's runnable state changes, and requeues, where a task
119 * and its state are being moved between CPUs and runqueues.
120 */
121static inline void psi_enqueue(struct task_struct *p, bool wakeup)
122{
123 int clear = 0, set = TSK_RUNNING;
124
125 if (static_branch_likely(&psi_disabled))
126 return;
127
128 if (p->in_memstall)
129 set |= TSK_MEMSTALL_RUNNING;
130
131 if (!wakeup) {
132 if (p->in_memstall)
133 set |= TSK_MEMSTALL;
134 } else {
135 if (p->in_iowait)
136 clear |= TSK_IOWAIT;
137 }
138
139 psi_task_change(p, clear, set);
140}
141
142static inline void psi_dequeue(struct task_struct *p, bool sleep)
143{
144 if (static_branch_likely(&psi_disabled))
145 return;
146
147 /*
148 * A voluntary sleep is a dequeue followed by a task switch. To
149 * avoid walking all ancestors twice, psi_task_switch() handles
150 * TSK_RUNNING and TSK_IOWAIT for us when it moves TSK_ONCPU.
151 * Do nothing here.
152 */
153 if (sleep)
154 return;
155
156 psi_task_change(p, p->psi_flags, 0);
157}
158
159static inline void psi_ttwu_dequeue(struct task_struct *p)
160{
161 if (static_branch_likely(&psi_disabled))
162 return;
163 /*
164 * Is the task being migrated during a wakeup? Make sure to
165 * deregister its sleep-persistent psi states from the old
166 * queue, and let psi_enqueue() know it has to requeue.
167 */
168 if (unlikely(p->psi_flags)) {
169 struct rq_flags rf;
170 struct rq *rq;
171
172 rq = __task_rq_lock(p, &rf);
173 psi_task_change(p, p->psi_flags, 0);
174 __task_rq_unlock(rq, &rf);
175 }
176}
177
178static inline void psi_sched_switch(struct task_struct *prev,
179 struct task_struct *next,
180 bool sleep)
181{
182 if (static_branch_likely(&psi_disabled))
183 return;
184
185 psi_task_switch(prev, next, sleep);
186}
187
188#else /* CONFIG_PSI */
189static inline void psi_enqueue(struct task_struct *p, bool wakeup) {}
190static inline void psi_dequeue(struct task_struct *p, bool sleep) {}
191static inline void psi_ttwu_dequeue(struct task_struct *p) {}
192static inline void psi_sched_switch(struct task_struct *prev,
193 struct task_struct *next,
194 bool sleep) {}
195static inline void psi_account_irqtime(struct task_struct *task, u32 delta) {}
196#endif /* CONFIG_PSI */
197
198#ifdef CONFIG_SCHED_INFO
199/*
200 * We are interested in knowing how long it was from the *first* time a
201 * task was queued to the time that it finally hit a CPU, we call this routine
202 * from dequeue_task() to account for possible rq->clock skew across CPUs. The
203 * delta taken on each CPU would annul the skew.
204 */
205static inline void sched_info_dequeue(struct rq *rq, struct task_struct *t)
206{
207 unsigned long long delta = 0;
208
209 if (!t->sched_info.last_queued)
210 return;
211
212 delta = rq_clock(rq) - t->sched_info.last_queued;
213 t->sched_info.last_queued = 0;
214 t->sched_info.run_delay += delta;
215
216 rq_sched_info_dequeue(rq, delta);
217}
218
219/*
220 * Called when a task finally hits the CPU. We can now calculate how
221 * long it was waiting to run. We also note when it began so that we
222 * can keep stats on how long its timeslice is.
223 */
224static void sched_info_arrive(struct rq *rq, struct task_struct *t)
225{
226 unsigned long long now, delta = 0;
227
228 if (!t->sched_info.last_queued)
229 return;
230
231 now = rq_clock(rq);
232 delta = now - t->sched_info.last_queued;
233 t->sched_info.last_queued = 0;
234 t->sched_info.run_delay += delta;
235 t->sched_info.last_arrival = now;
236 t->sched_info.pcount++;
237
238 rq_sched_info_arrive(rq, delta);
239}
240
241/*
242 * This function is only called from enqueue_task(), but also only updates
243 * the timestamp if it is already not set. It's assumed that
244 * sched_info_dequeue() will clear that stamp when appropriate.
245 */
246static inline void sched_info_enqueue(struct rq *rq, struct task_struct *t)
247{
248 if (!t->sched_info.last_queued)
249 t->sched_info.last_queued = rq_clock(rq);
250}
251
252/*
253 * Called when a process ceases being the active-running process involuntarily
254 * due, typically, to expiring its time slice (this may also be called when
255 * switching to the idle task). Now we can calculate how long we ran.
256 * Also, if the process is still in the TASK_RUNNING state, call
257 * sched_info_enqueue() to mark that it has now again started waiting on
258 * the runqueue.
259 */
260static inline void sched_info_depart(struct rq *rq, struct task_struct *t)
261{
262 unsigned long long delta = rq_clock(rq) - t->sched_info.last_arrival;
263
264 rq_sched_info_depart(rq, delta);
265
266 if (task_is_running(t))
267 sched_info_enqueue(rq, t);
268}
269
270/*
271 * Called when tasks are switched involuntarily due, typically, to expiring
272 * their time slice. (This may also be called when switching to or from
273 * the idle task.) We are only called when prev != next.
274 */
275static inline void
276sched_info_switch(struct rq *rq, struct task_struct *prev, struct task_struct *next)
277{
278 /*
279 * prev now departs the CPU. It's not interesting to record
280 * stats about how efficient we were at scheduling the idle
281 * process, however.
282 */
283 if (prev != rq->idle)
284 sched_info_depart(rq, prev);
285
286 if (next != rq->idle)
287 sched_info_arrive(rq, next);
288}
289
290#else /* !CONFIG_SCHED_INFO: */
291# define sched_info_enqueue(rq, t) do { } while (0)
292# define sched_info_dequeue(rq, t) do { } while (0)
293# define sched_info_switch(rq, t, next) do { } while (0)
294#endif /* CONFIG_SCHED_INFO */
295
296#endif /* _KERNEL_STATS_H */