test: add simple cpu benchmark test (fix #3026)

repos/os/src/test/cpu_bench/bogomips.h

@@ -0,0 +1,8 @@
+
+void bogomips() __attribute__((optimize("O0")));
+
+void bogomips()
+{
+	for (register unsigned i = 0; i < 1000000000; i++) ;
+};
+

repos/os/src/test/cpu_bench/linux/Makefile

@@ -0,0 +1,7 @@
+INC_DIR = $(PWD)/..
+
+cpu_bench: main.cc $(INC_DIR)/bogomips.h
+	g++ -I$(INC_DIR) -O2 -Wall -Wextra -Weffc++ -std=gnu++11 $< -o $@
+
+clean:
+	rm -f *~ cpu_bench

repos/os/src/test/cpu_bench/linux/main.cc

@@ -0,0 +1,48 @@
+#include <time.h>
+#include <stdio.h>
+
+#include <bogomips.h>
+
+struct Duration { unsigned long usecs; };
+
+
+struct Time
+{
+	timespec _timespec { 0, 0 };
+
+	Time()
+	{
+		clock_gettime(CLOCK_REALTIME, &_timespec);
+	}
+
+	Time(timespec timespec) : _timespec(timespec) { }
+
+	void print() const
+	{
+		printf("secs=%ld nsecs=%ld\n",
+		       (long)_timespec.tv_sec, (long)_timespec.tv_nsec);
+	}
+
+	static Duration duration(Time t1, Time t2)
+	{
+		auto usecs = [&] (timespec ts) {
+			return 1000UL*1000UL*((unsigned long)ts.tv_sec % 1000UL)
+			       + (unsigned long)ts.tv_nsec/1000UL; };
+
+		return Duration { usecs(t2._timespec) - usecs(t1._timespec) };
+	}
+};
+
+
+int main(int, char**)
+{
+	printf("bogomips test:\n");
+	Time s;
+	bogomips();
+	{
+		Time e;
+		Duration duration = Time::duration(s, e);
+		printf("2G bogus instructions in %ld msecs (%f BogoMIPS)\n",
+		       duration.usecs/1000, 2000000000 / (float)duration.usecs);
+	}
+}

repos/os/src/test/cpu_bench/main.cc

@@ -0,0 +1,30 @@
+/*
+ * \brief  Testing CPU performance
+ * \author Stefan Kalkowski
+ * \date   2018-10-22
+ *
+ */
+
+/*
+ * Copyright (C) 2018 Genode Labs GmbH
+ *
+ * This file is part of the Genode OS framework, which is distributed
+ * under the terms of the GNU Affero General Public License version 3.
+ */
+
+#include <base/component.h>
+#include <base/log.h>
+#include <timer_session/connection.h>
+
+#include <bogomips.h>
+
+void Component::construct(Genode::Env &env)
+{
+	Timer::Connection timer(env);
+	timer.msleep(2000);
+
+	Genode::log("Cpu testsuite started");
+	Genode::log("start bogomips");
+	bogomips();
+	Genode::log("finished bogomips");
+};

repos/os/src/test/cpu_bench/target.mk

@@ -0,0 +1,4 @@
+TARGET  = test-cpu
+SRC_CC  = main.cc
+INC_DIR = $(PRG_DIR)
+LIBS    = base