From 6c7d9537fe7003667472b83424ea3895fd77c41c Mon Sep 17 00:00:00 2001
From: Pavankumar Kondeti <pkondeti@codeaurora.org>
Date: Wed, 18 Dec 2019 08:38:28 +0530
Subject: [PATCH] sched/fair: Improve the scheduler

This change is for general scheduler improvement.

Change-Id: I7c3a073fa68d715dd3bdbed11e4f83e82046a3c0
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>
---
 kernel/sched/core.c  | 14 ++++++++------
 kernel/sched/sched.h |  1 +
 kernel/sched/walt.h  |  6 +++++-
 3 files changed, 14 insertions(+), 7 deletions(-)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index a1993537ea8e..8817bd9eb428 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -8444,7 +8444,7 @@ void sched_account_irqtime(int cpu, struct task_struct *curr,
 				u64 delta, u64 wallclock)
 {
 	struct rq *rq = cpu_rq(cpu);
-	unsigned long flags, nr_windows;
+	unsigned long flags, nr_ticks;
 	u64 cur_jiffies_ts;
 
 	raw_spin_lock_irqsave(&rq->lock, flags);
@@ -8460,18 +8460,20 @@ void sched_account_irqtime(int cpu, struct task_struct *curr,
 		walt_update_task_ravg(curr, rq, IRQ_UPDATE, sched_ktime_clock(),
 								delta);
 
-	nr_windows = cur_jiffies_ts - rq->irqload_ts;
+	nr_ticks = cur_jiffies_ts - rq->irqload_ts;
 
-	if (nr_windows) {
-		if (nr_windows < 10) {
+	if (nr_ticks) {
+		if (nr_ticks < 10) {
 			/* Decay CPU's irqload by 3/4 for each window. */
-			rq->avg_irqload *= (3 * nr_windows);
+			rq->avg_irqload *= (3 * nr_ticks);
 			rq->avg_irqload = div64_u64(rq->avg_irqload,
-							4 * nr_windows);
+							4 * nr_ticks);
 		} else {
 			rq->avg_irqload = 0;
 		}
 		rq->avg_irqload += rq->cur_irqload;
+		rq->high_irqload = (rq->avg_irqload >=
+				    sysctl_sched_cpu_high_irqload);
 		rq->cur_irqload = 0;
 	}
 
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index f4e0790c4b42..837360af7ba7 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -1076,6 +1076,7 @@ struct rq {
 	u64			cur_irqload;
 	u64			avg_irqload;
 	u64			irqload_ts;
+	bool			high_irqload;
 	struct task_struct	*ed_task;
 	struct cpu_cycle	cc;
 	u64			old_busy_time, old_busy_time_group;
diff --git a/kernel/sched/walt.h b/kernel/sched/walt.h
index 6b91d365ac60..d670cd053e6b 100644
--- a/kernel/sched/walt.h
+++ b/kernel/sched/walt.h
@@ -85,6 +85,10 @@ extern void __weak mark_task_starting(struct task_struct *p);
 extern void __weak set_window_start(struct rq *rq);
 extern bool __weak do_pl_notif(struct rq *rq);
 
+/*
+ * This is only for tracepoints to print the avg irq load. For
+ * task placment considerations, use sched_cpu_high_irqload().
+ */
 #define SCHED_HIGH_IRQ_TIMEOUT 3
 static inline u64 sched_irqload(int cpu)
 {
@@ -107,7 +111,7 @@ static inline u64 sched_irqload(int cpu)
 
 static inline int sched_cpu_high_irqload(int cpu)
 {
-	return sched_irqload(cpu) >= sysctl_sched_cpu_high_irqload;
+	return cpu_rq(cpu)->high_irqload;
 }
 
 static inline int exiting_task(struct task_struct *p)