Merge "startop: Add iorap.stress.memory tool to test system with less RAM"

startop/iorap/stress/Android.bp

@@ -0,0 +1,33 @@
+//
+// Copyright (C) 2020 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.
+//
+
+cc_binary {
+  name: "iorap.stress.memory",
+  srcs: ["main_memory.cc"],
+
+  cflags: [
+      "-Wall",
+      "-Wextra",
+      "-Werror",
+      "-Wno-unused-parameter"
+  ],
+
+  shared_libs: [
+      "libbase"
+  ],
+
+  host_supported: true,
+}

startop/iorap/stress/main_memory.cc

@@ -0,0 +1,126 @@
+//
+// Copyright (C) 2020 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 <chrono>
+#include <fstream>
+#include <iostream>
+#include <random>
+#include <string>
+
+#include <string.h>
+#include <stdlib.h>
+#include <sys/mman.h>
+
+#include <android-base/parseint.h>
+
+static constexpr size_t kBytesPerMb = 1048576;
+const size_t kMemoryAllocationSize = 2 * 1024 * kBytesPerMb;
+
+#define USE_MLOCKALL 0
+
+std::string GetProcessStatus(const char* key) {
+  // Build search pattern of key and separator.
+  std::string pattern(key);
+  pattern.push_back(':');
+
+  // Search for status lines starting with pattern.
+  std::ifstream fs("/proc/self/status");
+  std::string line;
+  while (std::getline(fs, line)) {
+    if (strncmp(pattern.c_str(), line.c_str(), pattern.size()) == 0) {
+      // Skip whitespace in matching line (if any).
+      size_t pos = line.find_first_not_of(" \t", pattern.size());
+      if (pos == std::string::npos) {
+        break;
+      }
+      return std::string(line, pos);
+    }
+  }
+  return "<unknown>";
+}
+
+int main(int argc, char** argv) {
+  size_t allocationSize = 0;
+  if (argc >= 2) {
+    if (!android::base::ParseUint(argv[1], /*out*/&allocationSize)) {
+      std::cerr << "Failed to parse the allocation size (must be 0,MAX_SIZE_T)" << std::endl;
+      return 1;
+    }
+  } else {
+    allocationSize = kMemoryAllocationSize;
+  }
+
+  void* mem = malloc(allocationSize);
+  if (mem == nullptr) {
+    std::cerr << "Malloc failed" << std::endl;
+    return 1;
+  }
+
+  volatile int* imem = static_cast<int *>(mem);  // don't optimize out memory usage
+
+  size_t imemCount = allocationSize / sizeof(int);
+
+  std::cout << "Allocated " << allocationSize << " bytes" << std::endl;
+
+  auto seed = std::chrono::high_resolution_clock::now().time_since_epoch().count();
+  std::mt19937 mt_rand(seed);
+
+  size_t randPrintCount = 10;
+
+  // Write random numbers:
+  // * Ensures each page is resident
+  // * Avoids zeroed out pages (zRAM)
+  // * Avoids same-page merging
+  for (size_t i = 0; i < imemCount; ++i) {
+    imem[i] = mt_rand();
+
+    if (i < randPrintCount) {
+      std::cout << "Generated random value: " << imem[i] << std::endl;
+    }
+  }
+
+#if USE_MLOCKALL
+  /*
+   * Lock all pages from the address space of this process.
+   */
+  if (mlockall(MCL_CURRENT | MCL_FUTURE) != 0) {
+    std::cerr << "Mlockall failed" << std::endl;
+    return 1;
+  }
+#else
+  // Use mlock because of the predictable VmLck size.
+  // Using mlockall tends to bring in anywhere from 2-2.5GB depending on the device.
+  if (mlock(mem, allocationSize) != 0) {
+    std::cerr << "Mlock failed" << std::endl;
+    return 1;
+  }
+#endif
+
+  // Validate memory is actually resident and locked with:
+  // $> cat /proc/$(pidof iorap.stress.memory)/status | grep VmLck
+  std::cout << "Locked memory (VmLck) = " << GetProcessStatus("VmLck") << std::endl;
+
+  std::cout << "Press any key to terminate" << std::endl;
+  int any_input;
+  std::cin >> any_input;
+
+  std::cout << "Terminating..." << std::endl;
+
+  munlockall();
+  free(mem);
+
+  return 0;
+}