Save running SW instance info, including its SiteInstance, into the ProcessManager.

content/browser/service_worker/service_worker_process_manager.h

 // Copyright 2014 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.
 
 #ifndef CONTENT_BROWSER_SERVICE_WORKER_SERVICE_WORKER_PROCESS_MANAGER_H_
 #define CONTENT_BROWSER_SERVICE_WORKER_SERVICE_WORKER_PROCESS_MANAGER_H_
 
+#include <map>
 #include <vector>
 
 #include "base/callback.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "content/common/service_worker/service_worker_status_code.h"
 
 class GURL;
 
 namespace content {
 
 class BrowserContext;
 class ServiceWorkerContextWrapper;
+class SiteInstance;
 
 // Interacts with the UI thread to keep RenderProcessHosts alive while the
 // ServiceWorker system is using them.  Each instance of
 // ServiceWorkerProcessManager is destroyed on the UI thread shortly after its
 // ServiceWorkerContextCore is destroyed on the IO thread.
 class CONTENT_EXPORT ServiceWorkerProcessManager {
  public:
   // |*this| must be owned by |context_wrapper|->context().
   explicit ServiceWorkerProcessManager(
       ServiceWorkerContextWrapper* context_wrapper);
 
   ~ServiceWorkerProcessManager();
 
   // Returns a reference to a running process suitable for starting the Service
   // Worker at |script_url|. Processes in |process_ids| will be checked in order
   // for existence, and if none exist, then a new process will be created. Posts
   // |callback| to the IO thread to indicate whether creation succeeded and the
   // process ID that has a new reference.
   //
   // Allocation can fail with SERVICE_WORKER_ERROR_START_WORKER_FAILED if
   // RenderProcessHost::Init fails.
   void AllocateWorkerProcess(
+      int embedded_worker_id,
       const std::vector<int>& process_ids,
       const GURL& script_url,
       const base::Callback<void(ServiceWorkerStatusCode, int process_id)>&
-          callback) const;
+          callback);
 
-  // Drops a reference to a process that was running a Service Worker.  This
-  // must match a call to AllocateWorkerProcess.
-  void ReleaseWorkerProcess(int process_id);
+  // Drops a reference to a process that was running a Service Worker, and its
+  // SiteInstance.  This must match a call to AllocateWorkerProcess.
+  void ReleaseWorkerProcess(int embedded_worker_id);

[dominicc (has gone to gerrit), 2014/05/20 02:01:18]

The parallelism of Allocate/ReleaseWorkerProcess both taking a worker ID in the
first arg is nice. (Although the diff with the method named mumbleProcess no
longer taking a process ID but a worker ID looked a little funky at first.)

[Jeffrey Yasskin, 2014/05/20 05:20:10]

I could rename them to ...For()?

 
-  // |increment_for_test| and |decrement_for_test| define how to look up a
-  // process by ID and increment or decrement its worker reference count. This
-  // must be called before any reference to this object escapes to another
-  // thread, and is considered part of construction.
-  void SetProcessRefcountOpsForTest(
-      const base::Callback<bool(int)>& increment_for_test,
-      const base::Callback<bool(int)>& decrement_for_test);
+  // Sets a single process ID that will be used for all embedded workers.  This
+  // bypasses the work of creating a process and managing its worker refcount so
+  // that unittests can run without a BrowserContext.  The test is in charge of
+  // making sure this is only called on the same thread as runs the UI message
+  // loop.
+  void SetProcessIdForTest(int process_id) {
+    process_id_for_test_ = process_id;
+  }
 
  private:
-  bool IncrementWorkerRefcountByPid(int process_id) const;
-  bool DecrementWorkerRefcountByPid(int process_id) const;
+  // Information about the process for an EmbeddedWorkerInstance.
+  struct ProcessInfo {
+    explicit ProcessInfo(const scoped_refptr<SiteInstance>& site_instance);
+    explicit ProcessInfo(int process_id);
+    ~ProcessInfo();
+
+    // Stores the SiteInstance the Worker lives inside. This needs to outlive
+    // the instance's use of its RPH to uphold assumptions in the
+    // ContentBrowserClient interface.
+    scoped_refptr<SiteInstance> site_instance;
+
+    // In case the process was allocated without using a SiteInstance, we need
+    // to store a process ID to decrement a worker reference on shutdown.
+    // TODO(jyasskin): Implement http://crbug.com/372045 or thread a frame_id in
+    // so all processes can be allocated with a SiteInstance.
+    int process_id;
+  };
 
   // These fields are only accessed on the UI thread after construction.
   // The reference cycle through context_wrapper_ is broken in
   // ServiceWorkerContextWrapper::Shutdown().
   scoped_refptr<ServiceWorkerContextWrapper> context_wrapper_;
-  base::Callback<bool(int)> increment_for_test_;
-  base::Callback<bool(int)> decrement_for_test_;
+
+  // Maps the ID of a running EmbeddedWorkerInstance to information about the
+  // process it's running inside. Since the Instances themselves live on the IO
+  // thread, this can be slightly out of date:
+  //  * instance_info_ is populated while an Instance is STARTING and before
+  //    it's RUNNING.
+  //  * instance_info_ is depopulated in a message sent as the Instance becomes
+  //    STOPPED.
+  std::map<int, ProcessInfo> instance_info_;
+
+  // In unit tests, this will be returned as the process for all
+  // EmbeddedWorkerInstances.
+  int process_id_for_test_;
 
   // Used to double-check that we don't access *this after it's destroyed.
   base::WeakPtrFactory<ServiceWorkerProcessManager> weak_this_factory_;
-  base::WeakPtr<ServiceWorkerProcessManager> weak_this_;
+  const base::WeakPtr<ServiceWorkerProcessManager> weak_this_;
 };
 
 }  // namespace content
 
 namespace base {
 // Specialized to post the deletion to the UI thread.
 template <>
 struct CONTENT_EXPORT DefaultDeleter<content::ServiceWorkerProcessManager> {
   void operator()(content::ServiceWorkerProcessManager* ptr) const;
 };
 }  // namespace base
 
 #endif  // CONTENT_BROWSER_SERVICE_WORKER_SERVICE_WORKER_PROCESS_MANAGER_H_