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);
+}