Implement native module to measure CPU time

packages/react-native/ReactCommon/react/nativemodule/cputime/CPUTime.h

@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#pragma once
+
+#ifdef USE_POSIX_TIME
+#include <time.h>
+#else
+#include <chrono>
+#endif
+
+#ifdef USE_POSIX_TIME
+
+namespace {
+const double NANOSECONDS_IN_A_SECOND = 1000000000;
+} // namespace
+
+#endif
+
+namespace facebook::react {
+
+#ifdef USE_POSIX_TIME
+
+inline double getCPUTimeNanos() {
+  struct timespec time {};
+  clock_gettime(CLOCK_THREAD_CPUTIME_ID, &time);
+  return static_cast<double>(time.tv_sec) * NANOSECONDS_IN_A_SECOND +
+      static_cast<double>(time.tv_nsec);
+}
+
+inline bool hasAccurateCPUTimeNanosForBenchmarks() {
+  return true;
+}
+
+#else
+
+inline double getCPUTimeNanos() {
+  auto now = std::chrono::steady_clock::now();
+  return static_cast<double>(
+      std::chrono::duration_cast<std::chrono::nanoseconds>(
+          now.time_since_epoch())
+          .count());
+}
+
+inline bool hasAccurateCPUTimeNanosForBenchmarks() {
+  return false;
+}
+
+#endif
+
+} // namespace facebook::react

packages/react-native/ReactCommon/react/nativemodule/cputime/NativeCPUTime.cpp

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+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#include "NativeCPUTime.h"
+
+#include "CPUTime.h"
+
+#ifdef RN_DISABLE_OSS_PLUGIN_HEADER
+#include "Plugins.h"
+#endif
+
+std::shared_ptr<facebook::react::TurboModule> NativeCPUTimeModuleProvider(
+    std::shared_ptr<facebook::react::CallInvoker> jsInvoker) {
+  return std::make_shared<facebook::react::NativeCPUTime>(std::move(jsInvoker));
+}
+
+namespace facebook::react {
+
+NativeCPUTime::NativeCPUTime(std::shared_ptr<CallInvoker> jsInvoker)
+    : NativeCPUTimeCxxSpec(std::move(jsInvoker)) {}
+
+double NativeCPUTime::getCPUTimeNanos(jsi::Runtime& /*runtime*/) {
+  return facebook::react::getCPUTimeNanos();
+}
+
+bool NativeCPUTime::hasAccurateCPUTimeNanosForBenchmarks(
+    jsi::Runtime& /*runtime*/) {
+  return facebook::react::hasAccurateCPUTimeNanosForBenchmarks();
+}
+
+} // namespace facebook::react

packages/react-native/ReactCommon/react/nativemodule/cputime/NativeCPUTime.h

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+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#pragma once
+
+#if __has_include("rncoreJSI.h") // Cmake headers on Android
+#include "rncoreJSI.h"
+#elif __has_include("FBReactNativeSpecJSI.h") // CocoaPod headers on Apple
+#include "FBReactNativeSpecJSI.h"
+#else
+#include <FBReactNativeSpec/FBReactNativeSpecJSI.h>
+#endif
+
+namespace facebook::react {
+
+class NativeCPUTime : public NativeCPUTimeCxxSpec<NativeCPUTime> {
+ public:
+  explicit NativeCPUTime(std::shared_ptr<CallInvoker> jsInvoker);
+
+  double getCPUTimeNanos(jsi::Runtime& runtime);
+  bool hasAccurateCPUTimeNanosForBenchmarks(jsi::Runtime& runtime);
+};
+
+} // namespace facebook::react

packages/react-native/src/private/specs/modules/NativeCPUTime.js

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+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @flow strict
+ * @format
+ */
+
+import type {TurboModule} from '../../../../Libraries/TurboModule/RCTExport';
+
+import * as TurboModuleRegistry from '../../../../Libraries/TurboModule/TurboModuleRegistry';
+
+/**
+ * This is an internal native module meant to be used for performance
+ * measurements and benchmarks. It is not meant to be used in production.
+ */
+export interface Spec extends TurboModule {
+  +getCPUTimeNanos: () => number;
+  +hasAccurateCPUTimeNanosForBenchmarks: () => boolean;
+}
+
+export default (TurboModuleRegistry.getEnforcing<Spec>('CPUTimeCxx'): Spec);