Add basic microbenchmarks.

PiperOrigin-RevId: 296104390

1 files changed, 53 insertions, 0 deletions

diff --git a/test/perf/linux/read_benchmark.cc b/test/perf/linux/read_benchmark.cc
new file mode 100644
index 000000000..62445867d
--- /dev/null
+++ b/test/perf/linux/read_benchmark.cc
@@ -0,0 +1,53 @@
+// Copyright 2020 The gVisor Authors.
+//
+// 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 <fcntl.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include "gtest/gtest.h"
+#include "benchmark/benchmark.h"
+#include "test/util/fs_util.h"
+#include "test/util/logging.h"
+#include "test/util/temp_path.h"
+#include "test/util/test_util.h"
+
+namespace gvisor {
+namespace testing {
+
+namespace {
+
+void BM_Read(benchmark::State& state) {
+  const int size = state.range(0);
+  const std::string contents(size, 0);
+  auto path = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFileWith(
+      GetAbsoluteTestTmpdir(), contents, TempPath::kDefaultFileMode));
+  FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Open(path.path(), O_RDONLY));
+
+  std::vector<char> buf(size);
+  for (auto _ : state) {
+    TEST_CHECK(PreadFd(fd.get(), buf.data(), buf.size(), 0) == size);
+  }
+
+  state.SetBytesProcessed(static_cast<int64_t>(size) *
+                          static_cast<int64_t>(state.iterations()));
+}
+
+BENCHMARK(BM_Read)->Range(1, 1 << 26)->UseRealTime();
+
+}  // namespace
+
+}  // namespace testing
+}  // namespace gvisor