DevTools: make possible profiling of scripts doing heavy calculations.

webkit/glue/devtools/js/profiler_agent.js

+// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+/**
+ * @fileoverview Provides communication interface to remote v8 profiler.
+ */
+goog.provide('devtools.ProfilerAgent');
+
+/**
+ * @constructor
+ */
+devtools.ProfilerAgent = function() {
+  RemoteProfilerAgent.DidGetActiveProfilerModules =
+      goog.bind(this.didGetActiveProfilerModules_, this);
+  RemoteProfilerAgent.DidGetLogLines =
+      goog.bind(this.didGetLogLines_, this);
+
+  /**
+   * Active profiler modules flags.
+   * @type {number}
+   */
+  this.activeProfilerModules_ =
+      devtools.ProfilerAgent.ProfilerModules.PROFILER_MODULE_NONE;
+
+  /**
+   * Interval for polling profiler state.
+   * @type {number}
+   */
+  this.getActiveProfilerModulesInterval_ = null;
+
+  /**
+   * Profiler log position.
+   * @type {number}
+   */
+  this.logPosition_ = 0;
+
+  /**
+   * Whether log contents retrieval must be forced next time.
+   * @type {boolean}
+   */
+  this.forceGetLogLines_ = false;
+
+  /**
+   * Profiler processor instance.
+   * @type {devtools.profiler.Processor}
+   */
+  this.profilerProcessor_ = new devtools.profiler.Processor();
+};
+
+
+/**
+ * A copy of enum from include/v8.h
+ * @enum {number}
+ */
+devtools.ProfilerAgent.ProfilerModules = {
+  PROFILER_MODULE_NONE: 0,
+  PROFILER_MODULE_CPU: 1,
+  PROFILER_MODULE_HEAP_STATS: 1 << 1,
+  PROFILER_MODULE_JS_CONSTRUCTORS: 1 << 2,
+  PROFILER_MODULE_HEAP_SNAPSHOT: 1 << 16
+};
+
+
+/**
+ * Resets profiler agent to its initial state.
+ */
+devtools.ProfilerAgent.prototype.reset = function() {
+  this.logPosition_ = 0;
+  this.activeProfilerModules_ =
+      devtools.ProfilerAgent.ProfilerModules.PROFILER_MODULE_NONE;
+};
+
+
+/**
+ * Sets up callbacks that deal with profiles processing.
+ */
+devtools.ProfilerAgent.prototype.setupProfilerProcessorCallbacks = function() {
+  // A temporary icon indicating that the profile is being processed.
+  var processingIcon = new WebInspector.SidebarTreeElement(
+      'profile-sidebar-tree-item',
+      WebInspector.UIString('Processing...'),
+      '', null, false);
+  var profilesSidebar = WebInspector.panels.profiles.getProfileType(
+      WebInspector.CPUProfileType.TypeId).treeElement;
+
+  this.profilerProcessor_.setCallbacks(
+      function onProfileProcessingStarted() {
+        // Set visually empty string. Subtitle hiding is done via styles
+        // manipulation which doesn't play well with dynamic append / removal.
+        processingIcon.subtitle = ' ';
+        profilesSidebar.appendChild(processingIcon);
+      },
+      function onProfileProcessingStatus(ticksCount) {
+        processingIcon.subtitle =
+            WebInspector.UIString('%d ticks processed', ticksCount);
+      },
+      function onProfileProcessingFinished(profile) {
+        profilesSidebar.removeChild(processingIcon);
+        profile.typeId = WebInspector.CPUProfileType.TypeId;
+        InspectorBackend.addFullProfile(profile);
+        WebInspector.addProfileHeader(profile);
+        // If no profile is currently shown, show the new one.
+        var profilesPanel = WebInspector.panels.profiles;
+        if (!profilesPanel.visibleView) {
+          profilesPanel.showProfile(profile);
+        }
+      }
+  );
+};
+
+
+/**
+ * Initializes profiling state.
+ */
+devtools.ProfilerAgent.prototype.initializeProfiling = function() {
+  this.setupProfilerProcessorCallbacks();
+  this.forceGetLogLines_ = true;
+  this.getActiveProfilerModulesInterval_ = setInterval(
+        function() { RemoteProfilerAgent.GetActiveProfilerModules(); }, 1000);
+};
+
+
+/**
+ * Starts profiling.
+ * @param {number} modules List of modules to enable.
+ */
+devtools.ProfilerAgent.prototype.startProfiling = function(modules) {
+  var cmd = new devtools.DebugCommand('profile', {
+      'modules': modules,
+      'command': 'resume'});
+  devtools.DebuggerAgent.sendCommand_(cmd);
+  RemoteToolsAgent.ExecuteVoidJavaScript();
+  if (modules &
+      devtools.ProfilerAgent.ProfilerModules.PROFILER_MODULE_HEAP_SNAPSHOT) {
+    var pos = this.logPosition_;
+    // Active modules will not change, instead, a snapshot will be logged.
+    setTimeout(function() { RemoteProfilerAgent.GetLogLines(pos); }, 500);
+  }
+};
+
+
+/**
+ * Stops profiling.
+ */
+devtools.ProfilerAgent.prototype.stopProfiling = function(modules) {
+  var cmd = new devtools.DebugCommand('profile', {
+      'modules': modules,
+      'command': 'pause'});
+  devtools.DebuggerAgent.sendCommand_(cmd);
+  RemoteToolsAgent.ExecuteVoidJavaScript();
+};
+
+
+/**
+ * Handles current profiler status.
+ * @param {number} modules List of active (started) modules.
+ */
+devtools.ProfilerAgent.prototype.didGetActiveProfilerModules_ = function(
+    modules) {
+  var profModules = devtools.ProfilerAgent.ProfilerModules;
+  var profModuleNone = profModules.PROFILER_MODULE_NONE;
+  if (this.forceGetLogLines_ ||
+      (modules != profModuleNone &&
+      this.activeProfilerModules_ == profModuleNone)) {
+    this.forceGetLogLines_ = false;
+    // Start to query log data.
+    RemoteProfilerAgent.GetLogLines(this.logPosition_);
+  }
+  this.activeProfilerModules_ = modules;
+  // Update buttons.
+  WebInspector.setRecordingProfile(modules & profModules.PROFILER_MODULE_CPU);
+};
+
+
+/**
+ * Handles a portion of a profiler log retrieved by GetLogLines call.
+ * @param {number} pos Current position in log.
+ * @param {string} log A portion of profiler log.
+ */
+devtools.ProfilerAgent.prototype.didGetLogLines_ = function(pos, log) {
+  this.logPosition_ = pos;
+  if (log.length > 0) {
+    this.profilerProcessor_.processLogChunk(log);
+  } else if (this.activeProfilerModules_ ==
+      devtools.ProfilerAgent.ProfilerModules.PROFILER_MODULE_NONE) {
+    // No new data and profiling is stopped---suspend log reading.
+    return;
+  }
+  setTimeout(function() { RemoteProfilerAgent.GetLogLines(pos); }, 500);
+};