Implement Cobalt wrappers for v8::CpuProfiler (#2037)

Implement Cobalt wrappers for v8::CpuProfiler

Provides a baseline cobalt-side implementation of the JS Self-Profiling
API (https://wicg.github.io/js-self-profiling/). Adds
Profiler::Profiler, which wraps a profile handle from a v8::CpuProfiler,
and relevant IDL bindings.

b/314179829

Co-authored-by: Ahmed Elzeiny <[email protected]>
(cherry picked from commit 2285d51)

cobalt/browser/BUILD.gn

@@ -168,6 +168,7 @@ static_library("browser") {
     "//cobalt/fetch",
     "//cobalt/h5vcc",
     "//cobalt/input",
+    "//cobalt/js_profiler",
     "//cobalt/layout",
     "//cobalt/loader",
     "//cobalt/math",

cobalt/browser/idl_files.gni

@@ -255,6 +255,9 @@ source_idl_files = [
   "//cobalt/xhr/xml_http_request.idl",
   "//cobalt/xhr/xml_http_request_event_target.idl",
   "//cobalt/xhr/xml_http_request_upload.idl",
+
+  "//cobalt/js_profiler/profiler.idl",
+  "//cobalt/js_profiler/profiler_trace_wrapper.idl",
 ]
 
 if (!is_gold) {
@@ -313,6 +316,11 @@ generated_header_idl_files = [
   "//cobalt/encoding/text_decode_options.idl",
   "//cobalt/encoding/text_decoder_options.idl",
   "//cobalt/encoding/text_encoder_encode_into_result.idl",
+  "//cobalt/js_profiler/profiler_frame.idl",
+  "//cobalt/js_profiler/profiler_init_options.idl",
+  "//cobalt/js_profiler/profiler_sample.idl",
+  "//cobalt/js_profiler/profiler_stack.idl",
+  "//cobalt/js_profiler/profiler_trace.idl",
   "//cobalt/h5vcc/h5vcc_crash_type.idl",
   "//cobalt/h5vcc/h5vcc_metric_type.idl",
   "//cobalt/h5vcc/h5vcc_storage_resource_type_quota_bytes_dictionary.idl",

cobalt/build/cobalt_configuration.py

@@ -143,6 +143,7 @@ def GetTestTargets(self):
         'persistent_settings_test',
         'png_utils_test',
         'poem_unittests',
+        'js_profiler_test',
         'renderer_test',
         'render_tree_test',
         'scroll_engine_tests',

cobalt/js_profiler/BUILD.gn

@@ -0,0 +1,53 @@
+# Copyright 2023 The Cobalt Authors. All Rights Reserved.
+#
+# 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.
+
+static_library("js_profiler") {
+  sources = [
+    "profiler.cc",
+    "profiler.h",
+    "profiler_trace_builder.cc",
+    "profiler_trace_builder.h",
+    "profiler_trace_wrapper.h",
+  ]
+
+  deps = [
+    "//cobalt/base",
+    "//cobalt/browser:generated_bindings",
+    "//cobalt/browser:generated_types",
+    "//cobalt/dom",
+    "//cobalt/script",
+    "//cobalt/script/v8c:engine",
+    "//cobalt/web",
+    "//third_party/chromium/media:media",
+    "//third_party/v8:cppgc",
+  ]
+}
+
+target(gtest_target_type, "js_profiler_test") {
+  testonly = true
+
+  sources = [ "js_profiler_test.cc" ]
+
+  deps = [
+    ":js_profiler",
+    "//cobalt/dom",
+    "//cobalt/dom/testing:dom_testing",
+    "//cobalt/dom/testing:dom_testing",
+    "//cobalt/script",
+    "//cobalt/test:run_all_unittests",
+    "//cobalt/web:dom_exception",
+    "//testing/gmock",
+    "//testing/gtest",
+  ]
+}

cobalt/js_profiler/js_profiler_test.cc

@@ -0,0 +1,115 @@
+// Copyright 2023 The Cobalt Authors. All Rights Reserved.
+//
+// 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 "base/callback.h"
+#include "base/memory/ref_counted.h"
+#include "cobalt/dom/testing/stub_environment_settings.h"
+#include "cobalt/dom/testing/stub_window.h"
+#include "cobalt/dom/testing/test_with_javascript.h"
+#include "cobalt/js_profiler/profiler.h"
+#include "cobalt/js_profiler/profiler_trace_wrapper.h"
+#include "cobalt/script/testing/mock_exception_state.h"
+#include "cobalt/web/dom_exception.h"
+#include "cobalt/web/environment_settings_helper.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+using ::testing::_;
+using ::testing::Return;
+using ::testing::StrictMock;
+
+namespace cobalt {
+namespace js_profiler {
+
+class ProfilerTest : public dom::testing::TestWithJavaScript {
+ public:
+  ProfilerTest() {}
+
+ protected:
+  dom::testing::StubWindow window_;
+  StrictMock<script::testing::MockExceptionState> exception_state_;
+};
+
+TEST_F(ProfilerTest, ProfilerStop) {
+  v8::HandleScope scope(web::get_isolate(window_.environment_settings()));
+  ProfilerInitOptions init_options;
+  init_options.set_sample_interval(10);
+  init_options.set_max_buffer_size(1000);
+
+  scoped_refptr<Profiler> profiler_(new Profiler(
+      window_.environment_settings(), init_options, &exception_state_));
+
+  auto promise = profiler_->Stop(window_.environment_settings());
+  EXPECT_EQ(profiler_->stopped(), true);
+  EXPECT_TRUE(promise->State() == cobalt::script::PromiseState::kPending);
+  base::RunLoop().RunUntilIdle();
+  EXPECT_TRUE(promise->State() == cobalt::script::PromiseState::kFulfilled);
+}
+
+TEST_F(ProfilerTest, ProfilerAlreadyStopped) {
+  v8::HandleScope scope(web::get_isolate(window_.environment_settings()));
+  ProfilerInitOptions init_options;
+  init_options.set_sample_interval(10);
+  init_options.set_max_buffer_size(0);
+
+  scoped_refptr<Profiler> profiler_(new Profiler(
+      window_.environment_settings(), init_options, &exception_state_));
+
+  auto promise = profiler_->Stop(window_.environment_settings());
+  EXPECT_EQ(profiler_->stopped(), true);
+  EXPECT_TRUE(promise->State() == cobalt::script::PromiseState::kPending);
+  base::RunLoop().RunUntilIdle();
+  EXPECT_TRUE(promise->State() == cobalt::script::PromiseState::kFulfilled);
+  auto promise2 = profiler_->Stop(window_.environment_settings());
+  EXPECT_TRUE(promise2->State() == cobalt::script::PromiseState::kRejected);
+}
+
+TEST_F(ProfilerTest, ProfilerZeroSampleInterval) {
+  v8::HandleScope scope(web::get_isolate(window_.environment_settings()));
+  ProfilerInitOptions init_options;
+  init_options.set_sample_interval(0);
+  init_options.set_max_buffer_size(0);
+
+  scoped_refptr<Profiler> profiler_(new Profiler(
+      window_.environment_settings(), init_options, &exception_state_));
+  EXPECT_EQ(profiler_->sample_interval(), 10);
+  auto promise = profiler_->Stop(window_.environment_settings());
+  EXPECT_EQ(profiler_->stopped(), true);
+  EXPECT_TRUE(promise->State() == cobalt::script::PromiseState::kPending);
+  base::RunLoop().RunUntilIdle();
+  EXPECT_TRUE(promise->State() == cobalt::script::PromiseState::kFulfilled);
+}
+
+TEST_F(ProfilerTest, ProfilerOutRangeSampleInterval) {
+  v8::HandleScope scope(web::get_isolate(window_.environment_settings()));
+  ProfilerInitOptions init_options;
+  init_options.set_sample_interval(-1);
+  init_options.set_max_buffer_size(0);
+
+  scoped_refptr<Profiler> profiler_(new Profiler(
+      window_.environment_settings(), init_options, &exception_state_));
+  EXPECT_EQ(profiler_->sample_interval(), 10);
+  auto promise = profiler_->Stop(window_.environment_settings());
+  EXPECT_EQ(profiler_->stopped(), true);
+  EXPECT_TRUE(promise->State() == cobalt::script::PromiseState::kPending);
+  base::RunLoop().RunUntilIdle();
+  EXPECT_TRUE(promise->State() == cobalt::script::PromiseState::kFulfilled);
+}
+
+TEST_F(ProfilerTest, ProfilerJSCode) {
+  std::string result;
+  EXPECT_TRUE(EvaluateScript("Profiler", &result));
+  EXPECT_EQ(result, "function Profiler() { [native code] }");
+}
+}  // namespace js_profiler
+}  // namespace cobalt

cobalt/js_profiler/profiler.cc

@@ -0,0 +1,158 @@
+// Copyright 2023 The Cobalt Authors. All Rights Reserved.
+//
+// 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 "cobalt/js_profiler/profiler.h"
+
+#include <iostream>
+#include <limits>
+#include <memory>
+#include <string>
+#include <utility>
+
+#include "cobalt/base/polymorphic_downcast.h"
+#include "cobalt/js_profiler/profiler_trace_builder.h"
+#include "cobalt/js_profiler/profiler_trace_wrapper.h"
+#include "cobalt/web/cache_utils.h"
+#include "cobalt/web/context.h"
+#include "cobalt/web/dom_exception.h"
+#include "cobalt/web/environment_settings.h"
+#include "cobalt/web/environment_settings_helper.h"
+
+namespace {
+v8::Local<v8::String> toV8String(v8::Isolate* isolate,
+                                 const std::string& string) {
+  if (string.empty()) return v8::String::Empty(isolate);
+  return v8::String::NewFromUtf8(isolate, string.c_str(),
+                                 v8::NewStringType::kNormal, string.length())
+      .ToLocalChecked();
+}
+}  // namespace
+
+namespace cobalt {
+namespace js_profiler {
+
+volatile uint32_t s_lastProfileId = 0;
+
+static constexpr int kBaseSampleIntervalMs = 10;
+
+Profiler::Profiler(script::EnvironmentSettings* settings,
+                   ProfilerInitOptions options,
+                   script::ExceptionState* exception_state)
+    : cobalt::web::EventTarget(settings),
+      stopped_(false),
+      time_origin_{base::TimeTicks::Now()} {
+  profiler_id_ = nextProfileId();
+
+  const base::TimeDelta sample_interval =
+      base::Milliseconds(options.sample_interval());
+
+  int64_t sample_interval_us = sample_interval.InMicroseconds();
+
+  if (sample_interval_us < 0 ||
+      sample_interval_us > std::numeric_limits<int>::max()) {
+    sample_interval_us = 0;
+  }
+
+  int effective_sample_interval_ms =
+      static_cast<int>(sample_interval.InMilliseconds());
+  if (effective_sample_interval_ms % kBaseSampleIntervalMs != 0 ||
+      effective_sample_interval_ms == 0) {
+    effective_sample_interval_ms +=
+        (kBaseSampleIntervalMs -
+         effective_sample_interval_ms % kBaseSampleIntervalMs);
+  }
+  sample_interval_ = effective_sample_interval_ms;
+
+  auto isolate = web::get_isolate(settings);
+
+  auto status = ImplProfilingStart(
+      profiler_id_,
+      v8::CpuProfilingOptions(v8::kLeafNodeLineNumbers,
+                              options.max_buffer_size(), sample_interval_us),
+      settings);
+
+  if (status == v8::CpuProfilingStatus::kAlreadyStarted) {
+    web::DOMException::Raise(web::DOMException::kInvalidStateErr,
+                             "Profiler Already started", exception_state);
+  } else if (status == v8::CpuProfilingStatus::kErrorTooManyProfilers) {
+    web::DOMException::Raise(web::DOMException::kInvalidStateErr,
+                             "Too Many Profilers", exception_state);
+  }
+}
+
+Profiler::~Profiler() {
+  if (cpu_profiler_) {
+    cpu_profiler_->Dispose();
+    cpu_profiler_ = nullptr;
+  }
+}
+
+v8::CpuProfilingStatus Profiler::ImplProfilingStart(
+    std::string profiler_id, v8::CpuProfilingOptions options,
+    script::EnvironmentSettings* settings) {
+  auto isolate = web::get_isolate(settings);
+  cpu_profiler_ = v8::CpuProfiler::New(isolate);
+  cpu_profiler_->SetSamplingInterval(kBaseSampleIntervalMs *
+                                     base::Time::kMicrosecondsPerMillisecond);
+  return cpu_profiler_->StartProfiling(
+      toV8String(isolate, profiler_id), options,
+      std::make_unique<ProfilerMaxSamplesDelegate>(this));
+}
+
+std::string Profiler::nextProfileId() {
+  s_lastProfileId++;
+  return "cobalt::profiler[" + std::to_string(s_lastProfileId) + "]";
+}
+
+void Profiler::PerformStop(
+    script::EnvironmentSettings* environment_settings,
+    std::unique_ptr<script::ValuePromiseWrappable::Reference> promise_reference,
+    base::TimeTicks time_origin, std::string profiler_id) {
+  auto isolate = web::get_isolate(environment_settings);
+  auto profile =
+      cpu_profiler_->StopProfiling(toV8String(isolate, profiler_id_));
+  auto trace = ProfilerTraceBuilder::FromProfile(profile, time_origin_);
+  scoped_refptr<ProfilerTraceWrapper> result(new ProfilerTraceWrapper(trace));
+  cpu_profiler_->Dispose();
+  cpu_profiler_ = nullptr;
+  promise_reference->value().Resolve(result);
+}
+
+Profiler::ProfilerTracePromise Profiler::Stop(
+    script::EnvironmentSettings* environment_settings) {
+  script::HandlePromiseWrappable promise =
+      web::get_script_value_factory(environment_settings)
+          ->CreateInterfacePromise<scoped_refptr<ProfilerTraceWrapper>>();
+  if (!stopped()) {
+    stopped_ = true;
+    auto* global_wrappable = web::get_global_wrappable(environment_settings);
+    auto* context = web::get_context(environment_settings);
+    std::unique_ptr<script::ValuePromiseWrappable::Reference> promise_reference(
+        new script::ValuePromiseWrappable::Reference(global_wrappable,
+                                                     promise));
+
+    context->message_loop()->task_runner()->PostTask(
+        FROM_HERE,
+        base::BindOnce(&Profiler::PerformStop, base::Unretained(this),
+                       environment_settings, std::move(promise_reference),
+                       std::move(time_origin_), std::move(profiler_id_)));
+  } else {
+    promise->Reject(new web::DOMException(web::DOMException::kInvalidStateErr,
+                                          "Profiler already stopped."));
+  }
+  return promise;
+}
+
+}  // namespace js_profiler
+}  // namespace cobalt