Collect samples for background threads.

runtime/vm/gc_sweeper.cc

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/gc_sweeper.h"
 
 #include "vm/freelist.h"
 #include "vm/globals.h"
 #include "vm/heap.h"
 #include "vm/lockers.h"
 #include "vm/pages.h"
 #include "vm/safepoint.h"
 #include "vm/thread_pool.h"
+#include "vm/timeline.h"
 
 namespace dart {
 
 bool GCSweeper::SweepPage(HeapPage* page, FreeList* freelist, bool locked) {
   // Keep track whether this page is still in use.
   bool in_use = false;
 
   bool is_executable = (page->type() == HeapPage::kExecutable);
   uword start = page->object_start();
   uword end = page->object_end();
@@ skipping 85 matching lines @@
     ASSERT(last_ != NULL);
     ASSERT(freelist_ != NULL);
     MonitorLocker ml(old_space_->tasks_lock());
     old_space_->set_tasks(old_space_->tasks() + 1);
     ml.Notify();
   }
 
   virtual void Run() {
     bool result = Thread::EnterIsolateAsHelper(task_isolate_);
     ASSERT(result);
-    Thread* thread = Thread::Current();
-    GCSweeper sweeper;
+    {
+      Thread* thread = Thread::Current();
+      TimelineDurationScope tds(thread, Timeline::GetGCStream(), "SweeperTask");
+      GCSweeper sweeper;
 
-    HeapPage* page = first_;
-    HeapPage* prev_page = NULL;
+      HeapPage* page = first_;
+      HeapPage* prev_page = NULL;
 
-    while (page != NULL) {
-      thread->CheckForSafepoint();
-      HeapPage* next_page = page->next();
-      ASSERT(page->type() == HeapPage::kData);
-      bool page_in_use = sweeper.SweepPage(page, freelist_, false);
-      if (page_in_use) {
-        prev_page = page;
-      } else {
-        old_space_->FreePage(page, prev_page);
+      while (page != NULL) {
+        thread->CheckForSafepoint();
+        HeapPage* next_page = page->next();
+        ASSERT(page->type() == HeapPage::kData);
+        bool page_in_use = sweeper.SweepPage(page, freelist_, false);
+        if (page_in_use) {
+          prev_page = page;
+        } else {
+          old_space_->FreePage(page, prev_page);
+        }
+        {
+          // Notify the mutator thread that we have added elements to the free
+          // list or that more capacity is available.
+          MonitorLocker ml(old_space_->tasks_lock());
+          ml.Notify();
+        }
+        if (page == last_) break;
+        page = next_page;
       }
-      {
-        // Notify the mutator thread that we have added elements to the free
-        // list or that more capacity is available.
-        MonitorLocker ml(old_space_->tasks_lock());
-        ml.Notify();
-      }
-      if (page == last_) break;
-      page = next_page;
     }
     // Exit isolate cleanly *before* notifying it, to avoid shutdown race.
     Thread::ExitIsolateAsHelper();
     // This sweeper task is done. Notify the original isolate.
     {
       MonitorLocker ml(old_space_->tasks_lock());
       old_space_->set_tasks(old_space_->tasks() - 1);
       ml.Notify();
     }
   }
@@ skipping 14 matching lines @@
   SweeperTask* task =
       new SweeperTask(isolate,
                       isolate->heap()->old_space(),
                       first, last,
                       freelist);
   ThreadPool* pool = Dart::thread_pool();
   pool->Run(task);
 }
 
 }  // namespace dart