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-rw-r--r--kernel/sched/stats.h231
1 files changed, 231 insertions, 0 deletions
diff --git a/kernel/sched/stats.h b/kernel/sched/stats.h
new file mode 100644
index 000000000000..2ef90a51ec5e
--- /dev/null
+++ b/kernel/sched/stats.h
@@ -0,0 +1,231 @@
+
+#ifdef CONFIG_SCHEDSTATS
+
+/*
+ * Expects runqueue lock to be held for atomicity of update
+ */
+static inline void
+rq_sched_info_arrive(struct rq *rq, unsigned long long delta)
+{
+ if (rq) {
+ rq->rq_sched_info.run_delay += delta;
+ rq->rq_sched_info.pcount++;
+ }
+}
+
+/*
+ * Expects runqueue lock to be held for atomicity of update
+ */
+static inline void
+rq_sched_info_depart(struct rq *rq, unsigned long long delta)
+{
+ if (rq)
+ rq->rq_cpu_time += delta;
+}
+
+static inline void
+rq_sched_info_dequeued(struct rq *rq, unsigned long long delta)
+{
+ if (rq)
+ rq->rq_sched_info.run_delay += delta;
+}
+# define schedstat_inc(rq, field) do { (rq)->field++; } while (0)
+# define schedstat_add(rq, field, amt) do { (rq)->field += (amt); } while (0)
+# define schedstat_set(var, val) do { var = (val); } while (0)
+#else /* !CONFIG_SCHEDSTATS */
+static inline void
+rq_sched_info_arrive(struct rq *rq, unsigned long long delta)
+{}
+static inline void
+rq_sched_info_dequeued(struct rq *rq, unsigned long long delta)
+{}
+static inline void
+rq_sched_info_depart(struct rq *rq, unsigned long long delta)
+{}
+# define schedstat_inc(rq, field) do { } while (0)
+# define schedstat_add(rq, field, amt) do { } while (0)
+# define schedstat_set(var, val) do { } while (0)
+#endif
+
+#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
+static inline void sched_info_reset_dequeued(struct task_struct *t)
+{
+ t->sched_info.last_queued = 0;
+}
+
+/*
+ * We are interested in knowing how long it was from the *first* time a
+ * task was queued to the time that it finally hit a cpu, we call this routine
+ * from dequeue_task() to account for possible rq->clock skew across cpus. The
+ * delta taken on each cpu would annul the skew.
+ */
+static inline void sched_info_dequeued(struct task_struct *t)
+{
+ unsigned long long now = task_rq(t)->clock, delta = 0;
+
+ if (unlikely(sched_info_on()))
+ if (t->sched_info.last_queued)
+ delta = now - t->sched_info.last_queued;
+ sched_info_reset_dequeued(t);
+ t->sched_info.run_delay += delta;
+
+ rq_sched_info_dequeued(task_rq(t), delta);
+}
+
+/*
+ * Called when a task finally hits the cpu. We can now calculate how
+ * long it was waiting to run. We also note when it began so that we
+ * can keep stats on how long its timeslice is.
+ */
+static void sched_info_arrive(struct task_struct *t)
+{
+ unsigned long long now = task_rq(t)->clock, delta = 0;
+
+ if (t->sched_info.last_queued)
+ delta = now - t->sched_info.last_queued;
+ sched_info_reset_dequeued(t);
+ t->sched_info.run_delay += delta;
+ t->sched_info.last_arrival = now;
+ t->sched_info.pcount++;
+
+ rq_sched_info_arrive(task_rq(t), delta);
+}
+
+/*
+ * This function is only called from enqueue_task(), but also only updates
+ * the timestamp if it is already not set. It's assumed that
+ * sched_info_dequeued() will clear that stamp when appropriate.
+ */
+static inline void sched_info_queued(struct task_struct *t)
+{
+ if (unlikely(sched_info_on()))
+ if (!t->sched_info.last_queued)
+ t->sched_info.last_queued = task_rq(t)->clock;
+}
+
+/*
+ * Called when a process ceases being the active-running process, either
+ * voluntarily or involuntarily. Now we can calculate how long we ran.
+ * Also, if the process is still in the TASK_RUNNING state, call
+ * sched_info_queued() to mark that it has now again started waiting on
+ * the runqueue.
+ */
+static inline void sched_info_depart(struct task_struct *t)
+{
+ unsigned long long delta = task_rq(t)->clock -
+ t->sched_info.last_arrival;
+
+ rq_sched_info_depart(task_rq(t), delta);
+
+ if (t->state == TASK_RUNNING)
+ sched_info_queued(t);
+}
+
+/*
+ * Called when tasks are switched involuntarily due, typically, to expiring
+ * their time slice. (This may also be called when switching to or from
+ * the idle task.) We are only called when prev != next.
+ */
+static inline void
+__sched_info_switch(struct task_struct *prev, struct task_struct *next)
+{
+ struct rq *rq = task_rq(prev);
+
+ /*
+ * prev now departs the cpu. It's not interesting to record
+ * stats about how efficient we were at scheduling the idle
+ * process, however.
+ */
+ if (prev != rq->idle)
+ sched_info_depart(prev);
+
+ if (next != rq->idle)
+ sched_info_arrive(next);
+}
+static inline void
+sched_info_switch(struct task_struct *prev, struct task_struct *next)
+{
+ if (unlikely(sched_info_on()))
+ __sched_info_switch(prev, next);
+}
+#else
+#define sched_info_queued(t) do { } while (0)
+#define sched_info_reset_dequeued(t) do { } while (0)
+#define sched_info_dequeued(t) do { } while (0)
+#define sched_info_switch(t, next) do { } while (0)
+#endif /* CONFIG_SCHEDSTATS || CONFIG_TASK_DELAY_ACCT */
+
+/*
+ * The following are functions that support scheduler-internal time accounting.
+ * These functions are generally called at the timer tick. None of this depends
+ * on CONFIG_SCHEDSTATS.
+ */
+
+/**
+ * account_group_user_time - Maintain utime for a thread group.
+ *
+ * @tsk: Pointer to task structure.
+ * @cputime: Time value by which to increment the utime field of the
+ * thread_group_cputime structure.
+ *
+ * If thread group time is being maintained, get the structure for the
+ * running CPU and update the utime field there.
+ */
+static inline void account_group_user_time(struct task_struct *tsk,
+ cputime_t cputime)
+{
+ struct thread_group_cputimer *cputimer = &tsk->signal->cputimer;
+
+ if (!cputimer->running)
+ return;
+
+ raw_spin_lock(&cputimer->lock);
+ cputimer->cputime.utime += cputime;
+ raw_spin_unlock(&cputimer->lock);
+}
+
+/**
+ * account_group_system_time - Maintain stime for a thread group.
+ *
+ * @tsk: Pointer to task structure.
+ * @cputime: Time value by which to increment the stime field of the
+ * thread_group_cputime structure.
+ *
+ * If thread group time is being maintained, get the structure for the
+ * running CPU and update the stime field there.
+ */
+static inline void account_group_system_time(struct task_struct *tsk,
+ cputime_t cputime)
+{
+ struct thread_group_cputimer *cputimer = &tsk->signal->cputimer;
+
+ if (!cputimer->running)
+ return;
+
+ raw_spin_lock(&cputimer->lock);
+ cputimer->cputime.stime += cputime;
+ raw_spin_unlock(&cputimer->lock);
+}
+
+/**
+ * account_group_exec_runtime - Maintain exec runtime for a thread group.
+ *
+ * @tsk: Pointer to task structure.
+ * @ns: Time value by which to increment the sum_exec_runtime field
+ * of the thread_group_cputime structure.
+ *
+ * If thread group time is being maintained, get the structure for the
+ * running CPU and update the sum_exec_runtime field there.
+ */
+static inline void account_group_exec_runtime(struct task_struct *tsk,
+ unsigned long long ns)
+{
+ struct thread_group_cputimer *cputimer = &tsk->signal->cputimer;
+
+ if (!cputimer->running)
+ return;
+
+ raw_spin_lock(&cputimer->lock);
+ cputimer->cputime.sum_exec_runtime += ns;
+ raw_spin_unlock(&cputimer->lock);
+}
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