gin: Make v8_context_snapshot.bin as a default snapshot blob

To make Chrome independent from snapshot_blob.bin, this CL makes v8_context_snapshot.bin as the default snapshot. As a background issue, if we want to use JS (=V8), we have to load a snapshot file on most platforms. It means we have to load either snapshot_blob.bin or v8_context_snapshot.bin. And some unit tests, e.g. net_unittests, do not need to use v8_context_snapshot.bin, and they don't want to depend on blink component. (It takes very long time just to create the snapshot.) This CL makes it possible to load either snapshot file depending on the order of function calls, and make dependencies clear. TBR=liberato Bug: 789964 Change-Id: I4df90ed5fe7be37ab969a7f7d5db79bf572ed02a Reviewed-on: https://chromium-review.googlesource.com/859577 Reviewed-by: Hitoshi Yoshida <peria@chromium.org> Reviewed-by: Ross McIlroy <rmcilroy@chromium.org> Reviewed-by: Kentaro Hara <haraken@chromium.org> Reviewed-by: Ken Rockot <rockot@chromium.org> Reviewed-by: Kinuko Yasuda <kinuko@chromium.org> Commit-Queue: Hitoshi Yoshida <peria@chromium.org> Cr-Commit-Position: refs/heads/master@{#530539}
FairyWorld · Jan 19, 2018 · 9aff02e · 9aff02e
1 parent 40534c4
commit 9aff02e
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Showing 13 changed files with 163 additions and 196 deletions.
diff --git a/content/app/BUILD.gn b/content/app/BUILD.gn
@@ -16,6 +16,7 @@ template("implement_content_app") {
   extra_configs = [
     "//build/config/compiler:wexit_time_destructors",
     "//content:content_implementation",
+    "//tools/v8_context_snapshot:use_v8_context_snapshot",
     "//v8:external_startup_data",
   ]
 

diff --git a/content/app/content_main_runner.cc b/content/app/content_main_runner.cc
@@ -169,39 +169,35 @@ void InitializeFieldTrialAndFeatureList(
 }
 
 #if defined(V8_USE_EXTERNAL_STARTUP_DATA)
-void LoadV8ContextSnapshotFile() {
-#if defined(OS_POSIX) && !defined(OS_MACOSX)
-  base::FileDescriptorStore& file_descriptor_store =
-      base::FileDescriptorStore::GetInstance();
-  base::MemoryMappedFile::Region region;
-  base::ScopedFD fd = file_descriptor_store.MaybeTakeFD(
-      kV8ContextSnapshotDataDescriptor, &region);
-  if (fd.is_valid()) {
-    gin::V8Initializer::LoadV8ContextSnapshotFromFD(fd.get(), region.offset,
-                                                    region.size);
-    return;
-  }
-#endif  // OS_POSIX && !OS_MACOSX
-#if !defined(CHROME_MULTIPLE_DLL_BROWSER)
-  gin::V8Initializer::LoadV8ContextSnapshot();
-#endif  // !CHROME_MULTIPLE_DLL_BROWSER
-}
 
 void LoadV8SnapshotFile() {
+#if defined(USE_V8_CONTEXT_SNAPSHOT)
+  static constexpr gin::V8Initializer::V8SnapshotFileType kSnapshotType =
+      gin::V8Initializer::V8SnapshotFileType::kWithAdditionalContext;
+  static const char* snapshot_data_descriptor =
+      kV8ContextSnapshotDataDescriptor;
+#else
+  static constexpr gin::V8Initializer::V8SnapshotFileType kSnapshotType =
+      gin::V8Initializer::V8SnapshotFileType::kDefault;
+  static const char* snapshot_data_descriptor = kV8SnapshotDataDescriptor;
+#endif  // USE_V8_CONTEXT_SNAPSHOT
+  ALLOW_UNUSED_LOCAL(kSnapshotType);
+  ALLOW_UNUSED_LOCAL(snapshot_data_descriptor);
+
 #if defined(OS_POSIX) && !defined(OS_MACOSX)
   base::FileDescriptorStore& file_descriptor_store =
       base::FileDescriptorStore::GetInstance();
   base::MemoryMappedFile::Region region;
   base::ScopedFD fd =
-      file_descriptor_store.MaybeTakeFD(kV8SnapshotDataDescriptor, &region);
+      file_descriptor_store.MaybeTakeFD(snapshot_data_descriptor, &region);
   if (fd.is_valid()) {
     gin::V8Initializer::LoadV8SnapshotFromFD(fd.get(), region.offset,
-                                             region.size);
+                                             region.size, kSnapshotType);
     return;
   }
 #endif  // OS_POSIX && !OS_MACOSX
 #if !defined(CHROME_MULTIPLE_DLL_BROWSER)
-  gin::V8Initializer::LoadV8Snapshot();
+  gin::V8Initializer::LoadV8Snapshot(kSnapshotType);
 #endif  // !CHROME_MULTIPLE_DLL_BROWSER
 }
 
@@ -232,7 +228,6 @@ void InitializeV8IfNeeded(const base::CommandLine& command_line,
 #if defined(V8_USE_EXTERNAL_STARTUP_DATA)
   LoadV8SnapshotFile();
   LoadV8NativesFile();
-  LoadV8ContextSnapshotFile();
 #endif  // V8_USE_EXTERNAL_STARTUP_DATA
 }
 

diff --git a/content/public/test/content_test_suite_base.cc b/content/public/test/content_test_suite_base.cc
@@ -32,6 +32,18 @@
 
 namespace content {
 
+namespace {
+#if defined(V8_USE_EXTERNAL_STARTUP_DATA)
+#if defined(USE_V8_CONTEXT_SNAPSHOT)
+constexpr gin::V8Initializer::V8SnapshotFileType kSnapshotType =
+    gin::V8Initializer::V8SnapshotFileType::kWithAdditionalContext;
+#else
+constexpr gin::V8Initializer::V8SnapshotFileType kSnapshotType =
+    gin::V8Initializer::V8SnapshotFileType::kDefault;
+#endif
+#endif
+}
+
 ContentTestSuiteBase::ContentTestSuiteBase(int argc, char** argv)
     : base::TestSuite(argc, argv) {
 }
@@ -40,14 +52,10 @@ void ContentTestSuiteBase::Initialize() {
   base::TestSuite::Initialize();
 
 #if defined(V8_USE_EXTERNAL_STARTUP_DATA)
-  gin::V8Initializer::LoadV8Snapshot();
+  gin::V8Initializer::LoadV8Snapshot(kSnapshotType);
   gin::V8Initializer::LoadV8Natives();
 #endif
 
-#if defined(USE_V8_CONTEXT_SNAPSHOT)
-  gin::V8Initializer::LoadV8ContextSnapshot();
-#endif
-
 #if defined(OS_ANDROID) && !defined(USE_AURA)
   content::Compositor::Initialize();
 #endif

diff --git a/content/shell/BUILD.gn b/content/shell/BUILD.gn
@@ -566,10 +566,6 @@ if (is_android) {
       "//tools/v8_context_snapshot:v8_context_snapshot",
     ]
 
-    data = [
-      "$root_out_dir/v8_context_snapshot.bin",
-    ]
-
     if (is_win) {
       deps += [ "//sandbox" ]
 

diff --git a/content/test/test_blink_web_unit_test_support.cc b/content/test/test_blink_web_unit_test_support.cc
@@ -117,6 +117,16 @@ class WebURLLoaderFactoryWithMock : public blink::WebURLLoaderFactory {
   DISALLOW_COPY_AND_ASSIGN(WebURLLoaderFactoryWithMock);
 };
 
+#if defined(V8_USE_EXTERNAL_STARTUP_DATA)
+#if defined(USE_V8_CONTEXT_SNAPSHOT)
+constexpr gin::V8Initializer::V8SnapshotFileType kSnapshotType =
+    gin::V8Initializer::V8SnapshotFileType::kWithAdditionalContext;
+#else
+constexpr gin::V8Initializer::V8SnapshotFileType kSnapshotType =
+    gin::V8Initializer::V8SnapshotFileType::kDefault;
+#endif
+#endif
+
 }  // namespace
 
 namespace content {
@@ -131,13 +141,10 @@ TestBlinkWebUnitTestSupport::TestBlinkWebUnitTestSupport()
   mock_clipboard_.reset(new MockWebClipboardImpl());
 
 #if defined(V8_USE_EXTERNAL_STARTUP_DATA)
-  gin::V8Initializer::LoadV8Snapshot();
+  gin::V8Initializer::LoadV8Snapshot(kSnapshotType);
   gin::V8Initializer::LoadV8Natives();
 #endif
 
-#if defined(USE_V8_CONTEXT_SNAPSHOT)
-  gin::V8Initializer::LoadV8ContextSnapshot();
-#endif
 
   scoped_refptr<base::SingleThreadTaskRunner> dummy_task_runner;
   std::unique_ptr<base::ThreadTaskRunnerHandle> dummy_task_runner_handle;

diff --git a/gin/isolate_holder.cc b/gin/isolate_holder.cc
@@ -41,56 +41,55 @@ IsolateHolder::IsolateHolder(
     : IsolateHolder(std::move(task_runner),
                     access_mode,
                     kAllowAtomicsWait,
-                    nullptr) {}
+                    IsolateCreationMode::kNormal) {}
 
 IsolateHolder::IsolateHolder(
     scoped_refptr<base::SingleThreadTaskRunner> task_runner,
     AccessMode access_mode,
     AllowAtomicsWaitMode atomics_wait_mode,
-    v8::StartupData* startup_data)
+    IsolateCreationMode isolate_creation_mode)
     : access_mode_(access_mode) {
+  DCHECK(task_runner);
+  DCHECK(task_runner->BelongsToCurrentThread());
+
   v8::ArrayBuffer::Allocator* allocator = g_array_buffer_allocator;
   CHECK(allocator) << "You need to invoke gin::IsolateHolder::Initialize first";
 
-  v8::Isolate::CreateParams params;
-  params.entry_hook = DebugImpl::GetFunctionEntryHook();
-  params.code_event_handler = DebugImpl::GetJitCodeEventHandler();
-  params.constraints.ConfigureDefaults(base::SysInfo::AmountOfPhysicalMemory(),
-                                       base::SysInfo::AmountOfVirtualMemory());
-  params.array_buffer_allocator = allocator;
-  params.allow_atomics_wait = atomics_wait_mode == kAllowAtomicsWait;
-  params.external_references = g_reference_table;
-
-  if (startup_data) {
-    CHECK(g_reference_table);
-    V8Initializer::GetV8ContextSnapshotData(startup_data);
-    if (startup_data->data) {
-      params.snapshot_blob = startup_data;
-    }
+  if (isolate_creation_mode == IsolateCreationMode::kCreateSnapshot) {
+    // This branch is called when creating a V8 snapshot for Blink.
+    // Note SnapshotCreator calls isolate->Enter() in its construction.
+    snapshot_creator_.reset(new v8::SnapshotCreator(g_reference_table));
+    isolate_ = snapshot_creator_->GetIsolate();
+  } else {
+    v8::Isolate::CreateParams params;
+    params.entry_hook = DebugImpl::GetFunctionEntryHook();
+    params.code_event_handler = DebugImpl::GetJitCodeEventHandler();
+    params.constraints.ConfigureDefaults(
+        base::SysInfo::AmountOfPhysicalMemory(),
+        base::SysInfo::AmountOfVirtualMemory());
+    params.array_buffer_allocator = allocator;
+    params.allow_atomics_wait =
+        atomics_wait_mode == AllowAtomicsWaitMode::kAllowAtomicsWait;
+    params.external_references = g_reference_table;
+
+    isolate_ = v8::Isolate::New(params);
   }
-  isolate_ = v8::Isolate::New(params);
 
-  SetUp(task_runner);
-}
-
-IsolateHolder::IsolateHolder(
-    scoped_refptr<base::SingleThreadTaskRunner> task_runner,
-    v8::StartupData* existing_blob)
-    : access_mode_(AccessMode::kSingleThread) {
-  CHECK(existing_blob);
-
-  v8::StartupData unused_natives;
-  V8Initializer::GetV8ExternalSnapshotData(&unused_natives, existing_blob);
-  if (!existing_blob->data) {
-    existing_blob = nullptr;
+  isolate_data_.reset(
+      new PerIsolateData(isolate_, allocator, access_mode_, task_runner));
+  isolate_memory_dump_provider_.reset(
+      new V8IsolateMemoryDumpProvider(this, task_runner));
+#if defined(OS_WIN)
+  {
+    void* code_range;
+    size_t size;
+    isolate_->GetCodeRange(&code_range, &size);
+    Debug::CodeRangeCreatedCallback callback =
+        DebugImpl::GetCodeRangeCreatedCallback();
+    if (code_range && size && callback)
+      callback(code_range, size);
   }
-
-  snapshot_creator_.reset(
-      new v8::SnapshotCreator(g_reference_table, existing_blob));
-  isolate_ = snapshot_creator_->GetIsolate();
-
-  DCHECK(task_runner->BelongsToCurrentThread());
-  SetUp(task_runner);
+#endif
 }
 
 IsolateHolder::~IsolateHolder() {
@@ -142,26 +141,4 @@ void IsolateHolder::EnableIdleTasks(
   isolate_data_->EnableIdleTasks(std::move(idle_task_runner));
 }
 
-void IsolateHolder::SetUp(
-    scoped_refptr<base::SingleThreadTaskRunner> task_runner) {
-  DCHECK(task_runner);
-  v8::ArrayBuffer::Allocator* allocator = g_array_buffer_allocator;
-  CHECK(allocator) << "You need to invoke gin::IsolateHolder::Initialize first";
-  isolate_data_.reset(
-      new PerIsolateData(isolate_, allocator, access_mode_, task_runner));
-  isolate_memory_dump_provider_.reset(
-      new V8IsolateMemoryDumpProvider(this, task_runner));
-#if defined(OS_WIN)
-  {
-    void* code_range;
-    size_t size;
-    isolate_->GetCodeRange(&code_range, &size);
-    Debug::CodeRangeCreatedCallback callback =
-        DebugImpl::GetCodeRangeCreatedCallback();
-    if (code_range && size && callback)
-      callback(code_range, size);
-  }
-#endif
-}
-
 }  // namespace gin
diff --git a/gin/public/isolate_holder.h b/gin/public/isolate_holder.h
@@ -53,20 +53,21 @@ class GIN_EXPORT IsolateHolder {
     kStableAndExperimentalV8Extras,
   };
 
+  // Indicates how the Isolate instance will be created.
+  enum class IsolateCreationMode {
+    kNormal,
+    kCreateSnapshot,
+  };
+
   explicit IsolateHolder(
       scoped_refptr<base::SingleThreadTaskRunner> task_runner);
   IsolateHolder(scoped_refptr<base::SingleThreadTaskRunner> task_runner,
                 AccessMode access_mode);
-  IsolateHolder(scoped_refptr<base::SingleThreadTaskRunner> task_runner,
-                AccessMode access_mode,
-                AllowAtomicsWaitMode atomics_wait_mode,
-                v8::StartupData* startup_data);
-
-  // This constructor is to create V8 snapshot for Blink.
-  // Note this constructor calls isolate->Enter() internally.
-  IsolateHolder(scoped_refptr<base::SingleThreadTaskRunner> task_runner,
-                v8::StartupData* existing_blob);
-
+  IsolateHolder(
+      scoped_refptr<base::SingleThreadTaskRunner> task_runner,
+      AccessMode access_mode,
+      AllowAtomicsWaitMode atomics_wait_mode,
+      IsolateCreationMode isolate_creation_mode = IsolateCreationMode::kNormal);
   ~IsolateHolder();
 
   // Should be invoked once before creating IsolateHolder instances to