Check that thread contexts are cleaned up during profiling

base/tracked_objects.cc

 // 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/tracked_objects.h"
 
 #include <math.h>
 
 #include "base/format_macros.h"
 #include "base/message_loop.h"
@@ skipping 106 matching lines @@
 // TODO(jar): We should pull all these static vars together, into a struct, and
 // optimize layout so that we benefit from locality of reference during accesses
 // to them.
 
 // A TLS slot which points to the ThreadData instance for the current thread. We
 // do a fake initialization here (zeroing out data), and then the real in-place
 // construction happens when we call tls_index_.Initialize().
 // static
 base::ThreadLocalStorage::Slot ThreadData::tls_index_(base::LINKER_INITIALIZED);
 
-// A lock-protected counter to assign sequence number to threads.
 // static
-int ThreadData::thread_number_counter_ = 0;
+int ThreadData::worker_thread_data_creation_count_ = 0;
+
+// static
+int ThreadData::cleanup_count_ = 0;
 
 // static
 int ThreadData::incarnation_counter_ = 0;
 
 // static
 ThreadData* ThreadData::all_thread_data_list_head_ = NULL;
 
 // static
 ThreadData* ThreadData::first_retired_worker_ = NULL;
 
@@ skipping 50 matching lines @@
 // static
 ThreadData* ThreadData::Get() {
   if (!tls_index_.initialized())
     return NULL;  // For unittests only.
   ThreadData* registered = reinterpret_cast<ThreadData*>(tls_index_.Get());
   if (registered)
     return registered;
 
   // We must be a worker thread, since we didn't pre-register.
   ThreadData* worker_thread_data = NULL;
-  int thread_number = 0;
+  int worker_thread_number = 0;
   {
     base::AutoLock lock(*list_lock_.Pointer());
     if (first_retired_worker_) {
       worker_thread_data = first_retired_worker_;
       first_retired_worker_ = first_retired_worker_->next_retired_worker_;
       worker_thread_data->next_retired_worker_ = NULL;
     } else {
-      thread_number = ++thread_number_counter_;
+      worker_thread_number = ++worker_thread_data_creation_count_;
     }
   }
 
   // If we can't find a previously used instance, then we have to create one.
-  if (!worker_thread_data)
-    worker_thread_data = new ThreadData(thread_number);
+  if (!worker_thread_data) {
+    DCHECK_GT(worker_thread_number, 0);
+    worker_thread_data = new ThreadData(worker_thread_number);
+  }
   DCHECK_GT(worker_thread_data->worker_thread_number_, 0);
 
   tls_index_.Set(worker_thread_data);
   return worker_thread_data;
 }
 
 // static
 void ThreadData::OnThreadTermination(void* thread_data) {
+  // We must NOT do any allocations during this callback. There is a chance
+  // that the allocator is not longer active on this thread.

[ramant (doing other things), 2011/11/21 04:14:06]

nit: not -> no

[jar (doing other things), 2011/11/21 17:22:30]

Done.

   if (!kTrackAllTaskObjects)
     return;  // Not compiled in.
   if (!thread_data)
     return;
   reinterpret_cast<ThreadData*>(thread_data)->OnThreadTerminationCleanup();
 }
 
 void ThreadData::OnThreadTerminationCleanup() {
-  if (!worker_thread_number_)
-    return;
+  // The list_lock_ was created when we registered the callback, so it won't be
+  // allocated here despite the lazy reference.
   base::AutoLock lock(*list_lock_.Pointer());
   if (incarnation_counter_ != incarnation_count_for_pool_)
     return;  // ThreadData was constructed in an earlier unit test.
+  ++cleanup_count_;
+  // Only worker threads deed to be retired and reused.

[ramant (doing other things), 2011/11/21 04:14:06]

nit: deed -> need?

[jar (doing other things), 2011/11/21 17:22:30]

Done.

+  if (!worker_thread_number_) {
+    return;
+  }
   // We must NOT do any allocations during this callback.
   // Using the simple linked lists avoids all allocations.
   DCHECK_EQ(this->next_retired_worker_, reinterpret_cast<ThreadData*>(NULL));
   this->next_retired_worker_ = first_retired_worker_;
   first_retired_worker_ = this;
 }
 
 // static
 base::DictionaryValue* ThreadData::ToValue() {
   DataCollector collected_data;  // Gather data.
   collected_data.AddListOfLivingObjects();  // Add births that are still alive.
   base::ListValue* list = collected_data.ToValue();
   base::DictionaryValue* dictionary = new base::DictionaryValue();
   dictionary->Set("list", list);
   return dictionary;
 }
 
 Births* ThreadData::TallyABirth(const Location& location) {
   BirthMap::iterator it = birth_map_.find(location);
   if (it != birth_map_.end()) {
     it->second->RecordBirth();
     return it->second;
   }
 
   Births* tracker = new Births(location, *this);
   // Lock since the map may get relocated now, and other threads sometimes
   // snapshot it (but they lock before copying it).
-  base::AutoLock lock(lock_);
+  base::AutoLock lock(map_lock_);
   birth_map_[location] = tracker;
   return tracker;
 }
 
 void ThreadData::TallyADeath(const Births& birth,
                              DurationInt queue_duration,
                              DurationInt run_duration) {
   DeathMap::iterator it = death_map_.find(&birth);
   DeathData* death_data;
   if (it != death_map_.end()) {
     death_data = &it->second;
   } else {
-    base::AutoLock lock(lock_);  // Lock since the map may get relocated now.
+    base::AutoLock lock(map_lock_);  // Lock as the map may get relocated now.
     death_data = &death_map_[&birth];
   }  // Release lock ASAP.
   death_data->RecordDeath(queue_duration, run_duration);
 }
 
 // static
 Births* ThreadData::TallyABirthIfActive(const Location& location) {
   if (!kTrackAllTaskObjects)
     return NULL;  // Not compiled in.
 
@@ skipping 112 matching lines @@
 }
 
 // static
 ThreadData* ThreadData::first() {
   base::AutoLock lock(*list_lock_.Pointer());
   return all_thread_data_list_head_;
 }
 
 // This may be called from another thread.
 void ThreadData::SnapshotBirthMap(BirthMap *output) const {
-  base::AutoLock lock(lock_);
+  base::AutoLock lock(map_lock_);
   for (BirthMap::const_iterator it = birth_map_.begin();
        it != birth_map_.end(); ++it)
     (*output)[it->first] = it->second;
 }
 
 // This may be called from another thread.
 void ThreadData::SnapshotDeathMap(DeathMap *output) const {
-  base::AutoLock lock(lock_);
+  base::AutoLock lock(map_lock_);
   for (DeathMap::const_iterator it = death_map_.begin();
        it != death_map_.end(); ++it)
     (*output)[it->first] = it->second;
 }
 
 // static
 void ThreadData::ResetAllThreadData() {
   ThreadData* my_list = first();
 
   for (ThreadData* thread_data = my_list;
        thread_data;
        thread_data = thread_data->next())
     thread_data->Reset();
 }
 
 void ThreadData::Reset() {
-  base::AutoLock lock(lock_);
+  base::AutoLock lock(map_lock_);
   for (DeathMap::iterator it = death_map_.begin();
        it != death_map_.end(); ++it)
     it->second.Clear();
   for (BirthMap::iterator it = birth_map_.begin();
        it != birth_map_.end(); ++it)
     it->second->Clear();
 }
 
 bool ThreadData::Initialize() {
   if (!kTrackAllTaskObjects)
@@ skipping 55 matching lines @@
 }
 
 // static
 TrackedTime ThreadData::Now() {
   if (kTrackAllTaskObjects && tracking_status())
     return TrackedTime::Now();
   return TrackedTime();  // Super fast when disabled, or not compiled.
 }
 
 // static
+void ThreadData::EnsureCleanupWasCalled(int major_threads_shutdown_count) {
+  base::AutoLock lock(*list_lock_.Pointer());
+  if (worker_thread_data_creation_count_ == 0)
+    return;  // We haven't really run much, and couldn't have leaked.
+  // Verify that we've at least shutdown/cleanup the major namesd threads, like

[ramant (doing other things), 2011/11/21 04:14:06]

nit: unfinished sentence?

[jar (doing other things), 2011/11/21 17:22:30]

Done.

+  CHECK_GT(cleanup_count_, major_threads_shutdown_count);
+}
+
+// static
 void ThreadData::ShutdownSingleThreadedCleanup(bool leak) {
   // This is only called from test code, where we need to cleanup so that
   // additional tests can be run.
   // We must be single threaded... but be careful anyway.
   if (!InitializeAndSetTrackingStatus(false))
     return;
   ThreadData* thread_data_list;
   {
     base::AutoLock lock(*list_lock_.Pointer());
     thread_data_list = all_thread_data_list_head_;
     all_thread_data_list_head_ = NULL;
     ++incarnation_counter_;
     // To be clean, break apart the retired worker list (though we leak them).
     while(first_retired_worker_) {
       ThreadData* worker = first_retired_worker_;
       CHECK_GT(worker->worker_thread_number_, 0);
       first_retired_worker_ = worker->next_retired_worker_;
       worker->next_retired_worker_ = NULL;
     }
   }
 
   // Put most global static back in pristine shape.
-  thread_number_counter_ = 0;
+  worker_thread_data_creation_count_ = 0;
+  cleanup_count_ = 0;
   tls_index_.Set(NULL);
   status_ = UNINITIALIZED;
 
   // To avoid any chance of racing in unit tests, which is the only place we
   // call this function, we may sometimes leak all the data structures we
   // recovered, as they may still be in use on threads from prior tests!
   if (leak)
     return;
 
   // When we want to cleanup (on a single thread), here is what we do.
@@ skipping 106 matching lines @@
 
 base::ListValue* DataCollector::ToValue() const {
   base::ListValue* list = new base::ListValue;
   for (size_t i = 0; i < collection_.size(); ++i) {
     list->Append(collection_[i].ToValue());
   }
   return list;
 }
 
 }  // namespace tracked_objects