Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 167 insertions, 0 deletions

diff --git a/kernel/sched/stats.h b/kernel/sched/stats.h
new file mode 100644
index 000000000..8aea199a3
--- /dev/null
+++ b/kernel/sched/stats.h
@@ -0,0 +1,167 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#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_enabled()		static_branch_unlikely(&sched_schedstats)
+#define __schedstat_inc(var)		do { var++; } while (0)
+#define   schedstat_inc(var)		do { if (schedstat_enabled()) { var++; } } while (0)
+#define __schedstat_add(var, amt)	do { var += (amt); } while (0)
+#define   schedstat_add(var, amt)	do { if (schedstat_enabled()) { var += (amt); } } while (0)
+#define __schedstat_set(var, val)	do { var = (val); } while (0)
+#define   schedstat_set(var, val)	do { if (schedstat_enabled()) { var = (val); } } while (0)
+#define   schedstat_val(var)		(var)
+#define   schedstat_val_or_zero(var)	((schedstat_enabled()) ? (var) : 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_enabled()		0
+# define __schedstat_inc(var)		do { } while (0)
+# define   schedstat_inc(var)		do { } while (0)
+# define __schedstat_add(var, amt)	do { } while (0)
+# define   schedstat_add(var, amt)	do { } while (0)
+# define __schedstat_set(var, val)	do { } while (0)
+# define   schedstat_set(var, val)	do { } while (0)
+# define   schedstat_val(var)		0
+# define   schedstat_val_or_zero(var)	0
+#endif /* CONFIG_SCHEDSTATS */
+
+#ifdef CONFIG_SCHED_INFO
+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 rq *rq, struct task_struct *t)
+{
+	unsigned long long now = rq_clock(rq), 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(rq, 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 rq *rq, struct task_struct *t)
+{
+	unsigned long long now = rq_clock(rq), 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(rq, 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 rq *rq, struct task_struct *t)
+{
+	if (unlikely(sched_info_on())) {
+		if (!t->sched_info.last_queued)
+			t->sched_info.last_queued = rq_clock(rq);
+	}
+}
+
+/*
+ * Called when a process ceases being the active-running process involuntarily
+ * due, typically, to expiring its time slice (this may also be called when
+ * switching to the idle task).  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 rq *rq, struct task_struct *t)
+{
+	unsigned long long delta = rq_clock(rq) - t->sched_info.last_arrival;
+
+	rq_sched_info_depart(rq, delta);
+
+	if (t->state == TASK_RUNNING)
+		sched_info_queued(rq, 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 rq *rq, struct task_struct *prev, struct task_struct *next)
+{
+	/*
+	 * 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(rq, prev);
+
+	if (next != rq->idle)
+		sched_info_arrive(rq, next);
+}
+
+static inline void
+sched_info_switch(struct rq *rq, struct task_struct *prev, struct task_struct *next)
+{
+	if (unlikely(sched_info_on()))
+		__sched_info_switch(rq, prev, next);
+}
+
+#else /* !CONFIG_SCHED_INFO: */
+# define sched_info_queued(rq, t)	do { } while (0)
+# define sched_info_reset_dequeued(t)	do { } while (0)
+# define sched_info_dequeued(rq, t)	do { } while (0)
+# define sched_info_depart(rq, t)	do { } while (0)
+# define sched_info_arrive(rq, next)	do { } while (0)
+# define sched_info_switch(rq, t, next)	do { } while (0)
+#endif /* CONFIG_SCHED_INFO */