Add verity open_read_close benchmark test

PiperOrigin-RevId: 388494554

test/perf/BUILD

@@ -160,3 +160,10 @@ syscall_test(
     test = "//test/perf/linux:verity_read_benchmark",
     vfs1 = False,
 )
+
+syscall_test(
+    size = "large",
+    debug = False,
+    test = "//test/perf/linux:verity_open_read_close_benchmark",
+    vfs1 = False,
+)

test/perf/linux/BUILD

@@ -424,3 +424,22 @@ cc_binary(
         "//test/util:verity_util",
     ],
 )
+
+cc_binary(
+    name = "verity_open_read_close_benchmark",
+    testonly = 1,
+    srcs = [
+        "verity_open_read_close_benchmark.cc",
+    ],
+    deps = [
+        gbenchmark,
+        gtest,
+        "//test/util:capability_util",
+        "//test/util:fs_util",
+        "//test/util:logging",
+        "//test/util:temp_path",
+        "//test/util:test_main",
+        "//test/util:test_util",
+        "//test/util:verity_util",
+    ],
+)

test/perf/linux/verity_open_read_close_benchmark.cc

@@ -0,0 +1,75 @@
+// Copyright 2021 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/mount.h>
+#include <unistd.h>
+
+#include <memory>
+#include <string>
+#include <vector>
+
+#include "gtest/gtest.h"
+#include "benchmark/benchmark.h"
+#include "test/util/capability_util.h"
+#include "test/util/fs_util.h"
+#include "test/util/logging.h"
+#include "test/util/temp_path.h"
+#include "test/util/test_util.h"
+#include "test/util/verity_util.h"
+
+namespace gvisor {
+namespace testing {
+
+namespace {
+
+void BM_VerityOpenReadClose(benchmark::State& state) {
+  const int size = state.range(0);
+
+  // Mount a tmpfs file system to be wrapped by a verity fs.
+  TempPath dir = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDir());
+  TEST_CHECK(mount("", dir.path().c_str(), "tmpfs", 0, "") == 0);
+
+  std::vector<TempPath> cache;
+  std::vector<EnableTarget> targets;
+
+  for (int i = 0; i < size; i++) {
+    auto file = ASSERT_NO_ERRNO_AND_VALUE(
+        TempPath::CreateFileWith(dir.path(), "some contents", 0644));
+    targets.emplace_back(
+        EnableTarget(std::string(Basename(file.path())), O_RDONLY));
+    cache.emplace_back(std::move(file));
+  }
+
+  std::string verity_dir =
+      TEST_CHECK_NO_ERRNO_AND_VALUE(MountVerity(dir.path(), targets));
+
+  char buf[1];
+  unsigned int seed = 1;
+  for (auto _ : state) {
+    const int chosen = rand_r(&seed) % size;
+    int fd = open(JoinPath(verity_dir, targets[chosen].path).c_str(), O_RDONLY);
+    TEST_CHECK(fd != -1);
+    TEST_CHECK(read(fd, buf, 1) == 1);
+    close(fd);
+  }
+}
+
+BENCHMARK(BM_VerityOpenReadClose)->Range(1000, 16384)->UseRealTime();
+
+}  // namespace
+
+}  // namespace testing
+}  // namespace gvisor