From 1afc3d9b7035782e091d9bb3e9643aac0b9cf93a Mon Sep 17 00:00:00 2001
From: Balazs Gerofi <bgerofi@riken.jp>
Date: Thu, 26 Sep 2019 12:24:18 +0900
Subject: [PATCH] Keep track of number of context switches per CPU

Change-Id: I7a2194c8777a7efcd34e1ed7f4734da03fb4d433
---
 kernel/include/cls.h | 1 +
 kernel/process.c     | 7 +++++--
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/kernel/include/cls.h b/kernel/include/cls.h
index e7e42a83..3ba98905 100644
--- a/kernel/include/cls.h
+++ b/kernel/include/cls.h
@@ -100,6 +100,7 @@ struct cpu_local_var {
 	int in_interrupt;
 	int no_preempt;
 	int timer_enabled;
+	unsigned long nr_ctx_switches;
 	int kmalloc_initialized;
 	struct ihk_os_cpu_monitor *monitor;
 	struct rusage_percpu *rusage;
diff --git a/kernel/process.c b/kernel/process.c
index b8224146..c00e29ea 100644
--- a/kernel/process.c
+++ b/kernel/process.c
@@ -3518,8 +3518,11 @@ void schedule(void)
 	set_timer(1);
 
 	if (switch_ctx) {
-		dkprintf("schedule: %d => %d \n",
-		        prev ? prev->tid : 0, next ? next->tid : 0);
+		++cpu_local_var(nr_ctx_switches);
+		dkprintf("%s: %d => %d [ctx sws: %lu]\n",
+				__func__,
+				prev ? prev->tid : 0, next ? next->tid : 0,
+				cpu_local_var(nr_ctx_switches));
 
 		if (prev && prev->ptrace_debugreg) {
 			save_debugreg(prev->ptrace_debugreg);