CPULimiter: Refactor class to manage the CPU limitation.
This new class replaces the functionality embedded in UpdateAttempter
that limits the max CPU usage allowed by update_engine. This refactor
helps reusing this class outside of the brillo UpdateAttempter.
Bug: None
TEST=FEATURES=test emerge-link update_engine
Change-Id: Ib5487d314846b497a44bb78a3b94609571e0fe38
diff --git a/common/cpu_limiter_unittest.cc b/common/cpu_limiter_unittest.cc
new file mode 100644
index 0000000..d549b4c
--- /dev/null
+++ b/common/cpu_limiter_unittest.cc
@@ -0,0 +1,42 @@
+//
+// Copyright (C) 2012 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "update_engine/common/cpu_limiter.h"
+
+#include <gtest/gtest.h>
+
+namespace chromeos_update_engine {
+
+class CPULimiterTest : public ::testing::Test {};
+
+namespace {
+// Compares cpu shares and returns an integer that is less
+// than, equal to or greater than 0 if |shares_lhs| is,
+// respectively, lower than, same as or higher than |shares_rhs|.
+int CompareCpuShares(CpuShares shares_lhs, CpuShares shares_rhs) {
+ return static_cast<int>(shares_lhs) - static_cast<int>(shares_rhs);
+}
+} // namespace
+
+// Tests the CPU shares enum is in the order we expect it.
+TEST(CPULimiterTest, CompareCpuSharesTest) {
+ EXPECT_LT(CompareCpuShares(CpuShares::kLow, CpuShares::kNormal), 0);
+ EXPECT_GT(CompareCpuShares(CpuShares::kNormal, CpuShares::kLow), 0);
+ EXPECT_EQ(CompareCpuShares(CpuShares::kNormal, CpuShares::kNormal), 0);
+ EXPECT_GT(CompareCpuShares(CpuShares::kHigh, CpuShares::kNormal), 0);
+}
+
+} // namespace chromeos_update_engine