Task manager tracking RenderProcessHosts processes

chrome/browser/task_manager/providers/render_process_host_task_provider.cc

+// Copyright 2015 The Chromium Authors. All rights reserved.

[ncarter (slow), 2017/07/28 17:46:29]

2017

[cburn, 2017/07/28 18:08:21]

Done.

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/task_manager/providers/render_process_host_task_provider.h"
+
+#include "base/process/process.h"
+#include "chrome/browser/task_manager/providers/child_process_task.h"
+#include "content/public/browser/browser_child_process_host_iterator.h"
+#include "content/public/browser/browser_thread.h"
+#include "content/public/browser/child_process_data.h"
+#include "content/public/browser/notification_service.h"
+#include "content/public/browser/notification_types.h"
+#include "content/public/browser/render_process_host.h"
+#include "content/public/common/process_type.h"
+#include "extensions/features/features.h"
+
+using content::RenderProcessHost;
+using content::BrowserThread;
+using content::ChildProcessData;
+
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+#include "extensions/browser/process_map.h"
+#endif
+
+namespace task_manager {
+
+RenderProcessHostTaskProvider::RenderProcessHostTaskProvider()
+    : weak_ptr_factory_(this) {
+  registrar_.Add(this, content::NOTIFICATION_RENDERER_PROCESS_CREATED,
+                 content::NotificationService::AllBrowserContextsAndSources());
+  registrar_.Add(this, content::NOTIFICATION_RENDERER_PROCESS_CLOSED,
+                 content::NotificationService::AllBrowserContextsAndSources());
+  registrar_.Add(this, content::NOTIFICATION_RENDERER_PROCESS_TERMINATED,
+                 content::NotificationService::AllBrowserContextsAndSources());
+}
+
+RenderProcessHostTaskProvider::~RenderProcessHostTaskProvider() {}
+
+Task* RenderProcessHostTaskProvider::GetTaskOfUrlRequest(int origin_pid,
+                                                         int child_id,
+                                                         int route_id) {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+  auto itr = tasks_by_rph_id_.find(child_id);
+  if (itr == tasks_by_rph_id_.end())
+    return nullptr;
+
+  return itr->second.get();
+}
+
+void RenderProcessHostTaskProvider::StartUpdating() {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+  DCHECK(tasks_by_rph_id_.empty());
+  for (RenderProcessHost::iterator it(RenderProcessHost::AllHostsIterator());
+       !it.IsAtEnd(); it.Advance()) {
+    RenderProcessHost* host = it.GetCurrentValue();
+    if (host->GetHandle()) {
+      CreateTask(host->GetID());
+    } else {
+      // If the host isn't ready do nothing and we will learn of its creation
+      // from the notification service.
+    }
+  }
+}
+
+void RenderProcessHostTaskProvider::StopUpdating() {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+
+  // ChildProcessDataCollected() should never be called after this, and hence

[ncarter (slow), 2017/07/28 17:46:29]

This comment looks like copy/paste cruft

[cburn, 2017/07/28 18:08:21]

It is. Done

+  // we must invalidate the weak pointers.
+  weak_ptr_factory_.InvalidateWeakPtrs();

[ncarter (slow), 2017/07/28 17:46:29]

It looks like we can remove the weak_ptr_factory_ member, right? We don't call
GetWeakPtr() anymore.

[cburn, 2017/07/28 18:08:21]

Yes, removed now. 

+
+  // Then delete all tasks (if any).
+  tasks_by_rph_id_.clear();
+}
+
+void RenderProcessHostTaskProvider::CreateTask(
+    const int render_process_host_id) {
+  // Checks that the task by RenderProcessHost ID isn't already a task in the
+  // map and deletes it if it is so they new task can be cleanly added.
+  DeleteTask(render_process_host_id);
+  std::unique_ptr<ChildProcessTask>& task =
+      tasks_by_rph_id_[render_process_host_id];
+
+  RenderProcessHost* host = RenderProcessHost::FromID(render_process_host_id);
+
+  // Create the task and notify the observer.
+  ChildProcessData data(content::PROCESS_TYPE_RENDERER);
+  data.handle = host->GetHandle();
+  data.id = host->GetID();
+  task.reset(new ChildProcessTask(data));
+  NotifyObserverTaskAdded(task.get());
+}
+
+void RenderProcessHostTaskProvider::DeleteTask(
+    const int render_process_host_id) {
+  auto itr = tasks_by_rph_id_.find(render_process_host_id);
+  // If the render process host id isn't being tracked in |tasks_by_rph_id| do
+  // nothing.
+  if (itr == tasks_by_rph_id_.end())
+    return;
+
+  NotifyObserverTaskRemoved(itr->second.get());
+
+  // Finally delete the task.
+  tasks_by_rph_id_.erase(itr);
+}
+
+void RenderProcessHostTaskProvider::Observe(
+    int type,
+    const content::NotificationSource& source,
+    const content::NotificationDetails& details) {
+  content::RenderProcessHost* host =
+      content::Source<content::RenderProcessHost>(source).ptr();
+  ChildProcessData data(content::PROCESS_TYPE_RENDERER);
+  switch (type) {
+    case content::NOTIFICATION_RENDERER_PROCESS_CREATED:
+      CreateTask(host->GetID());
+      break;
+    case content::NOTIFICATION_RENDERER_PROCESS_CLOSED:
+    case content::NOTIFICATION_RENDERER_PROCESS_TERMINATED:
+      DeleteTask(host->GetID());
+      break;
+    default:
+      NOTREACHED();
+      break;
+  }
+}
+
+}  // namespace task_manager