Track webcore worker message loops in chromium.

webkit/glue/worker_task_runner.cc

Index: webkit/glue/worker_task_runner.cc
diff --git a/webkit/glue/worker_task_runner.cc b/webkit/glue/worker_task_runner.cc
new file mode 100644
index 0000000000000000000000000000000000000000..d3037fecd2b98a5b2c7449c750ab13b07c3808b1
--- /dev/null
+++ b/webkit/glue/worker_task_runner.cc
@@ -0,0 +1,104 @@
+// Copyright (c) 2011 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.
+
+#include "base/callback.h"
+#include "base/lazy_instance.h"
+#include "base/logging.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/observer_list.h"
+#include "webkit/glue/worker_task_runner.h"
+
+using WebKit::WebWorkerRunLoop;
+
+namespace {
+
+class RunClosureTask : public WebKit::WebWorkerRunLoop::Task {
+ public:
+  RunClosureTask(const base::Closure& task) : task_(task) { }
+  virtual ~RunClosureTask() { }
+  virtual void Run() {
+    task_.Run();
+  }
+ private:
+  base::Closure task_;
+};
+
+} // unnamed namespace
+
+namespace webkit_glue {
+
+struct WorkerTaskRunner::ThreadLocalState {
+  int id_;
+  WebKit::WebWorkerRunLoop run_loop_;

[michaeln, 2011/12/10 01:19:32]

since your using this on line 12, no need for WebKit:: here

[dgrogan, 2011/12/10 01:37:40]

Done.

+  ObserverList<webkit_glue::WorkerTaskRunner::Observer> stop_observers_;

[michaeln, 2011/12/10 01:19:32]

no need for webkit_glue:: since we're in that namespace, and also since this is
an inner struct, no need for WorkerTaskRunner:: either (i think)

[dgrogan, 2011/12/10 01:37:40]

Done.

+};
+
+WorkerTaskRunner::WorkerTaskRunner() {
+  // Start worker ids at 1, 0 is reserved for the main thread.
+  DCHECK(!id_sequence_.GetNext());

[michaeln, 2011/12/10 01:19:32]

DCHECKs dont exist in release builds

[dgrogan, 2011/12/10 01:37:40]

Right.  Fixed.

+}
+
+void WorkerTaskRunner::PostTask(
+    int id, const base::Closure& closure) {
+  DCHECK(id > 0);
+  base::AutoLock locker_(loop_map_lock_);
+  IDToLoopMap::iterator found = loop_map_.find(id);
+  if (found != loop_map_.end())
+    found->second.postTask(new RunClosureTask(closure));
+}
+
+int WorkerTaskRunner::CurrentWorkerId() {
+  if (!current_tls_.Get())
+    return 0;
+  return current_tls_.Get()->id_;
+}
+
+WorkerTaskRunner* WorkerTaskRunner::Instance() {
+  static base::LazyInstance<WorkerTaskRunner,
+      base::LeakyLazyInstanceTraits<WorkerTaskRunner> >
+      worker_task_runner_ = LAZY_INSTANCE_INITIALIZER;

[michaeln, 2011/12/10 01:19:32]

this wrapping looks odd to me, can't distinguish between the type and the
variable name?

[dgrogan, 2011/12/10 01:37:40]

Any better?

[michaeln, 2011/12/10 02:08:34]

yes, thnx

+  return worker_task_runner_.Pointer();

[michaeln, 2011/12/10 01:19:32]

not a data member, so no need for the underbar, frequently these sort of globals
have a g_ prefix

[dgrogan, 2011/12/10 01:37:40]

Underscore removed.  I didn't add a g_ because it's not really global.

+}
+
+void WorkerTaskRunner::AddStopObserver(Observer* obs) {
+  DCHECK(CurrentWorkerId() > 0);
+  current_tls_.Get()->stop_observers_.AddObserver(obs);
+}
+
+void WorkerTaskRunner::RemoveStopObserver(Observer* obs) {
+  DCHECK(CurrentWorkerId() > 0);
+  current_tls_.Get()->stop_observers_.RemoveObserver(obs);
+}
+
+WorkerTaskRunner::~WorkerTaskRunner() {
+}
+
+void WorkerTaskRunner::OnWorkerRunLoopStarted(const WebWorkerRunLoop& loop) {
+  DCHECK(!CurrentWorkerId());
+  DCHECK(!current_tls_.Get());

[michaeln, 2011/12/10 01:19:32]

just the 2nd DCHECK is probably sufficient

[dgrogan, 2011/12/10 01:37:40]

Done.

+  int id = id_sequence_.GetNext();
+  ThreadLocalState* tls = new ThreadLocalState;

[michaeln, 2011/12/10 01:19:32]

a ctor might be nice...
  current_tls_.Set(new State(id, loop));

[dgrogan, 2011/12/10 01:37:40]

Done.

+  tls->id_ = id;
+  tls->run_loop_ = loop;
+  current_tls_.Set(tls);
+
+  base::AutoLock locker_(loop_map_lock_);
+  loop_map_[id] = loop;
+}
+
+void WorkerTaskRunner::OnWorkerRunLoopStopped(const WebWorkerRunLoop& loop) {
+  DCHECK(CurrentWorkerId() > 0);
+  DCHECK(current_tls_.Get());

[michaeln, 2011/12/10 01:19:32]

ditto

[dgrogan, 2011/12/10 01:37:40]

Done.

+  FOR_EACH_OBSERVER(Observer, current_tls_.Get()->stop_observers_,
+                    OnWorkerRunLoopStopped());
+
+  delete current_tls_.Get();

[dgrogan, 2011/12/10 01:11:12]

Oops, this has to go below the CurrentWorkerId call below.

+  current_tls_.Set(NULL);
+
+  base::AutoLock locker_(loop_map_lock_);
+  DCHECK(loop_map_[CurrentWorkerId()] == loop);

[michaeln, 2011/12/10 01:19:32]

is the value of CurrentWorkerId() always 0 at this point?

[dgrogan, 2011/12/10 01:37:40]

Yes, it was.  But now that the current_tls_ lines are below, it's not.

+  loop_map_.erase(CurrentWorkerId());
+}
+
+}  // namespace webkit_glue