DevTools Profiler: use sampling rate reported by V8 profiler....

webkit/glue/devtools/js/profiler_processor.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 Profiler processor is used to process log file produced
  * by V8 and produce an internal profile representation which is used
  * for building profile views in 'Profiles' tab.
  */
 goog.provide('devtools.profiler.Processor');
@@ skipping 59 matching lines @@
    */
   this.profiles_ = [];
 
   /**
    * The current profile.
    * @type {devtools.profiler.JsProfile}
    */
   this.currentProfile_ = null;
 
   /**
-   * Builder of profile views.
+   * Builder of profile views. Created during "profiler,begin" event processing.
    * @type {devtools.profiler.ViewBuilder}
    */
-  this.viewBuilder_ = new devtools.profiler.ViewBuilder(1);
+  this.viewBuilder_ = null;
 
   /**
    * Next profile id.
    * @type {number}
    */
   this.profileId_ = 1;
 };
 
 
 /**
  * A dispatch table for V8 profiler event log records.
  * @private
  */
 devtools.profiler.Processor.RecordsDispatch_ = {
   'code-creation': { parsers: [null, parseInt, parseInt, null],
                      processor: 'processCodeCreation_', needsProfile: true },
   'code-move': { parsers: [parseInt, parseInt],
                  processor: 'processCodeMove_', needsProfile: true },
   'code-delete': { parsers: [parseInt],
                    processor: 'processCodeDelete_', needsProfile: true },
   'tick': { parsers: [parseInt, parseInt, parseInt, 'var-args'],
             processor: 'processTick_', needsProfile: true },
-  'profiler': { parsers: [null], processor: 'processProfiler_',
+  'profiler': { parsers: [null, 'var-args'], processor: 'processProfiler_',
                 needsProfile: false },
   // Not used in DevTools Profiler.
   'shared-library': null,
   // Obsolete row types.
   'code-allocate': null,
   'begin-code-region': null,
   'end-code-region': null
 };
 
 
 /**
+ * Returns whether a profile is currently processed.
+ * @return {boolean}
+ */
+devtools.profiler.Processor.prototype.isProcessingProfile = function() {
+  return this.currentProfile_ != null;
+};
+
+
+/**
  * Sets new profile callback.
  * @param {function(devtools.profiler.ProfileView)} callback Callback function.
  */
 devtools.profiler.Processor.prototype.setNewProfileCallback = function(
     callback) {
   this.newProfileCallback_ = callback;
 };
 
 
 /**
@@ skipping 62 matching lines @@
       parsedFields.push(fields.slice(1 + i));
       break;
     }
   }
 
   // Run the processor.
   this[dispatch.processor].apply(this, parsedFields);
 };
 
 
-devtools.profiler.Processor.prototype.processProfiler_ = function(state) {
+devtools.profiler.Processor.prototype.processProfiler_ = function(state, params) {
   switch (state) {
     case "resume":
-      this.currentProfile_ = new devtools.profiler.JsProfile();
-      this.profiles_.push(this.currentProfile_);
+      if (this.currentProfile_ == null) {
+        this.currentProfile_ = new devtools.profiler.JsProfile();
+        this.profiles_.push(this.currentProfile_);
+      }
       break;
     case "pause":
       if (this.currentProfile_ != null) {
         this.newProfileCallback_(this.createProfileForView());
         this.currentProfile_ = null;
       }
       break;
-    // These events are valid but are not used.
-    case "begin": break;
+    case "begin":
+      var samplingRate = NaN;
+      if (params.length > 0) {
+        samplingRate = parseInt(params[0]);
+      }
+      if (isNaN(samplingRate)) {
+        samplingRate = 1;
+      }
+      this.viewBuilder_ = new devtools.profiler.ViewBuilder(samplingRate);
+      break;
+    // This event is valid but isn't used.
     case "end": break;
     default:
       throw new Error("unknown profiler state: " + state);
   }
 };
 
 
 devtools.profiler.Processor.prototype.processCodeCreation_ = function(
     type, start, size, name) {
   this.currentProfile_.addCode(type, name, start, size);
@@ skipping 33 matching lines @@
   profile.title = UserInitiatedProfileName + '.' + profile.uid;
   // A trick to cope with ProfileView.bottomUpProfileDataGridTree and
   // ProfileView.topDownProfileDataGridTree behavior.
   profile.head = profile;
   profile.heavyProfile = this.viewBuilder_.buildView(
       this.currentProfile_.getBottomUpProfile(), true);
   profile.treeProfile = this.viewBuilder_.buildView(
       this.currentProfile_.getTopDownProfile());
   return profile;
 };