From d847f6469ad7771fed1f52aa9e466a7365af9c67 Mon Sep 17 00:00:00 2001
From: Eric Frias <efrias@syncad.com>
Date: Sun, 27 Jul 2014 17:37:21 -0400
Subject: [PATCH] Allow us to require assigning descriptions to all async tasks
 to aid in debugging

---
 include/fc/signals.hpp        |  4 ++--
 include/fc/thread/future.hpp  | 15 +++++++++++----
 include/fc/thread/task.hpp    |  4 ++--
 include/fc/thread/thread.hpp  | 20 ++++++++++----------
 src/asio.cpp                  |  4 ++--
 src/io/iostream.cpp           |  4 ++--
 src/log/file_appender.cpp     | 12 ++++++------
 src/network/rate_limiting.cpp |  8 ++++----
 src/network/udt_socket.cpp    |  2 +-
 src/rpc/json_connection.cpp   | 22 +++++++++++-----------
 src/thread/task.cpp           |  1 +
 src/thread/thread.cpp         |  9 ++++-----
 src/thread/thread_d.hpp       |  2 +-
 tests/task_cancel.cpp         | 24 ++++++++++++++++++------
 14 files changed, 75 insertions(+), 56 deletions(-)

diff --git a/include/fc/signals.hpp b/include/fc/signals.hpp
index 632f4f4..9a7fc12 100644
--- a/include/fc/signals.hpp
+++ b/include/fc/signals.hpp
@@ -26,13 +26,13 @@ namespace fc {
 
    template<typename T>
    inline T wait( boost::signals2::signal<void(T)>& sig, const microseconds& timeout_us=microseconds::maximum() ) {
-     typename promise<T>::ptr p(new promise<T>());
+     typename promise<T>::ptr p(new promise<T>("fc::signal::wait"));
      boost::signals2::scoped_connection c( sig.connect( [=]( T t ) { p->set_value(t); } )); 
      return p->wait( timeout_us ); 
    }
 
    inline void wait( boost::signals2::signal<void()>& sig, const microseconds& timeout_us=microseconds::maximum() ) {
-     promise<void>::ptr p(new promise<void>());
+     promise<void>::ptr p(new promise<void>("fc::signal::wait"));
      boost::signals2::scoped_connection c( sig.connect( [=]() { p->set_value(); } )); 
      p->wait( timeout_us ); 
    }
diff --git a/include/fc/thread/future.hpp b/include/fc/thread/future.hpp
index 4c0757c..2ae2ef6 100644
--- a/include/fc/thread/future.hpp
+++ b/include/fc/thread/future.hpp
@@ -6,6 +6,13 @@
 #include <fc/thread/spin_yield_lock.hpp>
 #include <fc/optional.hpp>
 
+//#define FC_TASK_NAMES_ARE_MANDATORY 1
+#ifdef FC_TASK_NAMES_ARE_MANDATORY
+# define FC_TASK_NAME_DEFAULT_ARG
+#else
+# define FC_TASK_NAME_DEFAULT_ARG = "?"
+#endif
+
 namespace fc {
   class abstract_thread;
   struct void_t{};
@@ -47,7 +54,7 @@ namespace fc {
   class promise_base : public virtual retainable{
     public:
       typedef fc::shared_ptr<promise_base> ptr;
-      promise_base(const char* desc="?");
+      promise_base(const char* desc FC_TASK_NAME_DEFAULT_ARG);
 
       const char* get_desc()const;
                    
@@ -92,7 +99,7 @@ namespace fc {
   class promise : virtual public promise_base {
     public:
       typedef fc::shared_ptr< promise<T> > ptr;
-      promise( const char* desc = "?" ):promise_base(desc){}
+      promise( const char* desc FC_TASK_NAME_DEFAULT_ARG):promise_base(desc){}
       promise( const T& val ){ set_value(val); }
       promise( T&& val ){ set_value(fc::move(val) ); }
     
@@ -128,8 +135,8 @@ namespace fc {
   class promise<void> : virtual public promise_base {
     public:
       typedef fc::shared_ptr< promise<void> > ptr;
-      promise( const char* desc = "?" ):promise_base(desc){}
-      promise( const void_t& ){ set_value(); }
+      promise( const char* desc FC_TASK_NAME_DEFAULT_ARG):promise_base(desc){}
+      //promise( const void_t& ){ set_value(); }
     
       void wait(const microseconds& timeout = microseconds::maximum() ){
         this->_wait( timeout );
diff --git a/include/fc/thread/task.hpp b/include/fc/thread/task.hpp
index 5c1b30e..22e8ce5 100644
--- a/include/fc/thread/task.hpp
+++ b/include/fc/thread/task.hpp
@@ -61,7 +61,7 @@ namespace fc {
   class task : virtual public task_base, virtual public promise<R> {
     public:
       template<typename Functor>
-      task( Functor&& f ):task_base(&_functor) {
+      task( Functor&& f, const char* desc ):task_base(&_functor), promise_base(desc), promise<R>(desc) {
         typedef typename fc::deduce<Functor>::type FunctorType;
         static_assert( sizeof(f) <= sizeof(_functor), "sizeof(Functor) is larger than FunctorSize" );
         new ((char*)&_functor) FunctorType( fc::forward<Functor>(f) );
@@ -78,7 +78,7 @@ namespace fc {
   class task<void,FunctorSize> : virtual public task_base, virtual public promise<void> {
     public:
       template<typename Functor>
-      task( Functor&& f ):task_base(&_functor) {
+      task( Functor&& f, const char* desc ):task_base(&_functor), promise_base(desc), promise<void>(desc) {
         typedef typename fc::deduce<Functor>::type FunctorType;
         static_assert( sizeof(f) <= sizeof(_functor), "sizeof(Functor) is larger than FunctorSize"  );
         new ((char*)&_functor) FunctorType( fc::forward<Functor>(f) );
diff --git a/include/fc/thread/thread.hpp b/include/fc/thread/thread.hpp
index a133ba4..e6f01c8 100644
--- a/include/fc/thread/thread.hpp
+++ b/include/fc/thread/thread.hpp
@@ -52,13 +52,13 @@ namespace fc {
        *  @param prio the priority relative to other tasks
        */
       template<typename Functor>
-      auto async( Functor&& f, const char* desc ="", priority prio = priority()) -> fc::future<decltype(f())> {
+      auto async( Functor&& f, const char* desc FC_TASK_NAME_DEFAULT_ARG, priority prio = priority()) -> fc::future<decltype(f())> {
          typedef decltype(f()) Result;
          typedef typename fc::deduce<Functor>::type FunctorType;
          fc::task<Result,sizeof(FunctorType)>* tsk = 
-              new fc::task<Result,sizeof(FunctorType)>( fc::forward<Functor>(f) );
+              new fc::task<Result,sizeof(FunctorType)>( fc::forward<Functor>(f), desc );
          fc::future<Result> r(fc::shared_ptr< fc::promise<Result> >(tsk,true) );
-         async_task(tsk,prio,desc);
+         async_task(tsk,prio);
          return r;
       }
       void poke();
@@ -75,12 +75,12 @@ namespace fc {
        */
       template<typename Functor>
       auto schedule( Functor&& f, const fc::time_point& when, 
-                     const char* desc = "", priority prio = priority()) -> fc::future<decltype(f())> {
+                     const char* desc FC_TASK_NAME_DEFAULT_ARG, priority prio = priority()) -> fc::future<decltype(f())> {
          typedef decltype(f()) Result;
          fc::task<Result,sizeof(Functor)>* tsk = 
-              new fc::task<Result,sizeof(Functor)>( fc::forward<Functor>(f) );
+              new fc::task<Result,sizeof(Functor)>( fc::forward<Functor>(f), desc );
          fc::future<Result> r(fc::shared_ptr< fc::promise<Result> >(tsk,true) );
-         async_task(tsk,prio,when,desc);
+         async_task(tsk,prio,when);
          return r;
       }
      
@@ -133,8 +133,8 @@ namespace fc {
       void  exec();
       int  wait_any_until( std::vector<promise_base::ptr>&& v, const time_point& );
 
-      void async_task( task_base* t, const priority& p, const char* desc );
-      void async_task( task_base* t, const priority& p, const time_point& tp, const char* desc );
+      void async_task( task_base* t, const priority& p );
+      void async_task( task_base* t, const priority& p, const time_point& tp );
       class thread_d* my;
 
   };
@@ -172,11 +172,11 @@ namespace fc {
    int wait_any_until( std::vector<promise_base::ptr>&& v, const time_point& tp );
 
    template<typename Functor>
-   auto async( Functor&& f, const char* desc ="", priority prio = priority()) -> fc::future<decltype(f())> {
+   auto async( Functor&& f, const char* desc FC_TASK_NAME_DEFAULT_ARG, priority prio = priority()) -> fc::future<decltype(f())> {
       return fc::thread::current().async( fc::forward<Functor>(f), desc, prio );
    }
    template<typename Functor>
-   auto schedule( Functor&& f, const fc::time_point& t, const char* desc ="", priority prio = priority()) -> fc::future<decltype(f())> {
+   auto schedule( Functor&& f, const fc::time_point& t, const char* desc FC_TASK_NAME_DEFAULT_ARG, priority prio = priority()) -> fc::future<decltype(f())> {
       return fc::thread::current().schedule( fc::forward<Functor>(f), t, desc, prio );
    }
 
diff --git a/src/asio.cpp b/src/asio.cpp
index e618c2d..357f1ad 100644
--- a/src/asio.cpp
+++ b/src/asio.cpp
@@ -120,7 +120,7 @@ namespace fc {
     namespace tcp {
         std::vector<boost::asio::ip::tcp::endpoint> resolve( const std::string& hostname, const std::string& port) {
             resolver res( fc::asio::default_io_service() );
-            promise<std::vector<boost::asio::ip::tcp::endpoint> >::ptr p( new promise<std::vector<boost::asio::ip::tcp::endpoint> >() );
+            promise<std::vector<boost::asio::ip::tcp::endpoint> >::ptr p( new promise<std::vector<boost::asio::ip::tcp::endpoint> >("tcp::resolve completion") );
             res.async_resolve( boost::asio::ip::tcp::resolver::query(hostname,port), 
                              boost::bind( detail::resolve_handler<boost::asio::ip::tcp::endpoint,resolver_iterator>, p, _1, _2 ) );
             return p->wait();;
@@ -129,7 +129,7 @@ namespace fc {
     namespace udp {
                 std::vector<udp::endpoint> resolve( resolver& r, const std::string& hostname, const std::string& port) {
                 resolver res( fc::asio::default_io_service() );
-                promise<std::vector<endpoint> >::ptr p( new promise<std::vector<endpoint> >() );
+                promise<std::vector<endpoint> >::ptr p( new promise<std::vector<endpoint> >("udp::resolve completion") );
                 res.async_resolve( resolver::query(hostname,port), 
                                     boost::bind( detail::resolve_handler<endpoint,resolver_iterator>, p, _1, _2 ) );
                 return p->wait();
diff --git a/src/io/iostream.cpp b/src/io/iostream.cpp
index 7ad272d..6eef009 100644
--- a/src/io/iostream.cpp
+++ b/src/io/iostream.cpp
@@ -25,7 +25,7 @@ namespace fc {
       std::cin.read(&c,1);
       while( !std::cin.eof() ) {
         while( write_pos - read_pos > 0xfffff ) {
-          fc::promise<void>::ptr wr( new fc::promise<void>() );
+          fc::promise<void>::ptr wr( new fc::promise<void>("cin_buffer::write_ready") );
           write_ready = wr;
           if( write_pos - read_pos <= 0xfffff ) {
             wr->wait();
@@ -141,7 +141,7 @@ namespace fc {
     do {
         while( !b.eof &&  (b.write_pos - b.read_pos)==0 ){ 
            // wait for more... 
-           fc::promise<void>::ptr rr( new fc::promise<void>() );
+           fc::promise<void>::ptr rr( new fc::promise<void>("cin_buffer::read_ready") );
            {  // copy read_ready because it is accessed from multiple threads
              fc::scoped_lock<boost::mutex> lock( b.read_ready_mutex ); 
              b.read_ready = rr;
diff --git a/src/log/file_appender.cpp b/src/log/file_appender.cpp
index d53c1fc..014fd09 100644
--- a/src/log/file_appender.cpp
+++ b/src/log/file_appender.cpp
@@ -28,9 +28,9 @@ namespace fc {
 
          time_point_sec get_file_start_time( const time_point_sec& timestamp, const microseconds& interval )
          {
-             const auto interval_seconds = interval.to_seconds();
-             const auto file_number = timestamp.sec_since_epoch() / interval_seconds;
-             return time_point_sec( file_number * interval_seconds );
+             int64_t interval_seconds = interval.to_seconds();
+             int64_t file_number = timestamp.sec_since_epoch() / interval_seconds;
+             return time_point_sec( (uint32_t)(file_number * interval_seconds) );
          }
 
          string timestamp_to_string( const time_point_sec& timestamp )
@@ -74,7 +74,7 @@ namespace fc {
                  if( cfg.rotation_compression )
                      _compression_thread.reset( new thread( "compression") );
 
-                 _rotation_task = async( [this]() { rotate_files( true ); }, "rotate_files" );
+                 _rotation_task = async( [this]() { rotate_files( true ); }, "rotate_files(1)" );
              }
          }
 
@@ -114,7 +114,7 @@ namespace fc {
                {
                    if( start_time <= _current_file_start_time )
                    {
-                       _rotation_task = schedule( [this]() { rotate_files(); }, _current_file_start_time + cfg.rotation_interval.to_seconds(), "log_rotation_task" );
+                       _rotation_task = schedule( [this]() { rotate_files(); }, _current_file_start_time + cfg.rotation_interval.to_seconds(), "rotate_files(2)" );
                        return;
                    }
 
@@ -160,7 +160,7 @@ namespace fc {
              }
 
              _current_file_start_time = start_time;
-             _rotation_task = schedule( [this]() { rotate_files(); }, _current_file_start_time + cfg.rotation_interval.to_seconds() );
+             _rotation_task = schedule( [this]() { rotate_files(); }, _current_file_start_time + cfg.rotation_interval.to_seconds(), "rotate_files(3)" );
          }
    };
    file_appender::config::config( const fc::path& p  )
diff --git a/src/network/rate_limiting.cpp b/src/network/rate_limiting.cpp
index ad90f4b..aac30ae 100644
--- a/src/network/rate_limiting.cpp
+++ b/src/network/rate_limiting.cpp
@@ -207,7 +207,7 @@ namespace fc
       size_t bytes_read;
       if (_download_bytes_per_second)
       {
-        promise<size_t>::ptr completion_promise(new promise<size_t>());
+        promise<size_t>::ptr completion_promise(new promise<size_t>("rate_limiting_group_impl::readsome"));
         rate_limited_tcp_read_operation read_operation(socket, buffer, length, completion_promise);
         _read_operations_for_next_iteration.push_back(&read_operation);
 
@@ -232,7 +232,7 @@ namespace fc
       size_t bytes_written;
       if (_upload_bytes_per_second)
       {
-        promise<size_t>::ptr completion_promise(new promise<size_t>());
+        promise<size_t>::ptr completion_promise(new promise<size_t>("rate_limiting_group_impl::writesome"));
         rate_limited_tcp_write_operation write_operation(socket, buffer, length, completion_promise);
         _write_operations_for_next_iteration.push_back(&write_operation);
 
@@ -259,7 +259,7 @@ namespace fc
         process_pending_operations(_last_read_iteration_time, _download_bytes_per_second,
                                    _read_operations_in_progress, _read_operations_for_next_iteration, _read_tokens, _unused_read_tokens);
 
-        _new_read_operation_available_promise = new promise<void>();
+        _new_read_operation_available_promise = new promise<void>("rate_limiting_group_impl::process_pending_reads");
         try
         {
           if (_read_operations_in_progress.empty())
@@ -280,7 +280,7 @@ namespace fc
         process_pending_operations(_last_write_iteration_time, _upload_bytes_per_second,
                                    _write_operations_in_progress, _write_operations_for_next_iteration, _write_tokens, _unused_write_tokens);
 
-        _new_write_operation_available_promise = new promise<void>();
+        _new_write_operation_available_promise = new promise<void>("rate_limiting_group_impl::process_pending_writes");
         try
         {
           if (_write_operations_in_progress.empty())
diff --git a/src/network/udt_socket.cpp b/src/network/udt_socket.cpp
index 464c55c..0018238 100644
--- a/src/network/udt_socket.cpp
+++ b/src/network/udt_socket.cpp
@@ -194,7 +194,7 @@ namespace fc {
       connect_thread.async( [&](){
          if( UDT::ERROR == UDT::connect(_udt_socket_id, (sockaddr*)&serv_addr, sizeof(serv_addr)) )
             check_udt_errors();
-      }).wait();
+      }, "udt_socket::connect_to").wait();
 
       bool block = false;
       UDT::setsockopt(_udt_socket_id, 0, UDT_SNDSYN, &block, sizeof(bool));
diff --git a/src/rpc/json_connection.cpp b/src/rpc/json_connection.cpp
index fa6273b..06d3fa4 100644
--- a/src/rpc/json_connection.cpp
+++ b/src/rpc/json_connection.cpp
@@ -324,7 +324,7 @@ namespace fc { namespace rpc {
    future<variant> json_connection::async_call( const fc::string& method, const variants& args )
    {
       auto id = my->_next_id++;
-      my->_awaiting[id] = fc::promise<variant>::ptr( new fc::promise<variant>() );
+      my->_awaiting[id] = fc::promise<variant>::ptr( new fc::promise<variant>("json_connection::async_call") );
 
       {
          fc::scoped_lock<fc::mutex> lock(my->_write_mutex);
@@ -350,7 +350,7 @@ namespace fc { namespace rpc {
    future<variant> json_connection::async_call( const fc::string& method, const variant& a1 )
    {
       auto id = my->_next_id++;
-      my->_awaiting[id] = fc::promise<variant>::ptr( new fc::promise<variant>() );
+      my->_awaiting[id] = fc::promise<variant>::ptr( new fc::promise<variant>("json_connection::async_call") );
 
       {
          fc::scoped_lock<fc::mutex> lock(my->_write_mutex);
@@ -368,7 +368,7 @@ namespace fc { namespace rpc {
    future<variant> json_connection::async_call( const fc::string& method, const variant& a1, const variant& a2 )
    {
       auto id = my->_next_id++;
-      my->_awaiting[id] = fc::promise<variant>::ptr( new fc::promise<variant>() );
+      my->_awaiting[id] = fc::promise<variant>::ptr( new fc::promise<variant>("json_connection::async_call") );
 
       {
          fc::scoped_lock<fc::mutex> lock(my->_write_mutex);
@@ -388,7 +388,7 @@ namespace fc { namespace rpc {
    future<variant> json_connection::async_call( const fc::string& method, const variant& a1, const variant& a2, const variant& a3 )
    {
       auto id = my->_next_id++;
-      my->_awaiting[id] = fc::promise<variant>::ptr( new fc::promise<variant>() );
+      my->_awaiting[id] = fc::promise<variant>::ptr( new fc::promise<variant>("json_connection::async_call") );
 
       {
          fc::scoped_lock<fc::mutex> lock(my->_write_mutex);
@@ -411,7 +411,7 @@ namespace fc { namespace rpc {
    future<variant> json_connection::async_call( const fc::string& method, const variant& a1, const variant& a2, const variant& a3, const variant& a4 )
    {
       auto id = my->_next_id++;
-      my->_awaiting[id] = fc::promise<variant>::ptr( new fc::promise<variant>() );
+      my->_awaiting[id] = fc::promise<variant>::ptr( new fc::promise<variant>("json_connection::async_call") );
 
       {
          fc::scoped_lock<fc::mutex> lock(my->_write_mutex);
@@ -436,7 +436,7 @@ namespace fc { namespace rpc {
    future<variant> json_connection::async_call( const fc::string& method, const variant& a1, const variant& a2, const variant& a3, const variant& a4, const variant& a5 )
    {
       auto id = my->_next_id++;
-      my->_awaiting[id] = fc::promise<variant>::ptr( new fc::promise<variant>() );
+      my->_awaiting[id] = fc::promise<variant>::ptr( new fc::promise<variant>("json_connection::async_call") );
 
       {
          fc::scoped_lock<fc::mutex> lock(my->_write_mutex);
@@ -463,7 +463,7 @@ namespace fc { namespace rpc {
    future<variant> json_connection::async_call( const fc::string& method, const variant& a1, const variant& a2, const variant& a3, const variant& a4, const variant& a5, const variant& a6 )
    {
       auto id = my->_next_id++;
-      my->_awaiting[id] = fc::promise<variant>::ptr( new fc::promise<variant>() );
+      my->_awaiting[id] = fc::promise<variant>::ptr( new fc::promise<variant>("json_connection::async_call") );
 
       {
          fc::scoped_lock<fc::mutex> lock(my->_write_mutex);
@@ -491,7 +491,7 @@ namespace fc { namespace rpc {
    future<variant> json_connection::async_call( const fc::string& method, const variant& a1, const variant& a2, const variant& a3, const variant& a4, const variant& a5, const variant& a6, const variant& a7 )
    {
       auto id = my->_next_id++;
-      my->_awaiting[id] = fc::promise<variant>::ptr( new fc::promise<variant>() );
+      my->_awaiting[id] = fc::promise<variant>::ptr( new fc::promise<variant>("json_connection::async_call") );
 
       {
          fc::scoped_lock<fc::mutex> lock(my->_write_mutex);
@@ -525,7 +525,7 @@ namespace fc { namespace rpc {
                                                 const variant& a4, const variant& a5, const variant& a6, const variant& a7, const variant& a8 )
    {
       auto id = my->_next_id++;
-      my->_awaiting[id] = fc::promise<variant>::ptr( new fc::promise<variant>() );
+      my->_awaiting[id] = fc::promise<variant>::ptr( new fc::promise<variant>("json_connection::async_call") );
 
       {
          fc::scoped_lock<fc::mutex> lock(my->_write_mutex);
@@ -562,7 +562,7 @@ namespace fc { namespace rpc {
    future<variant> json_connection::async_call( const fc::string& method, const variant_object& named_args )
    {
       auto id = my->_next_id++;
-      my->_awaiting[id] = fc::promise<variant>::ptr( new fc::promise<variant>() );
+      my->_awaiting[id] = fc::promise<variant>::ptr( new fc::promise<variant>("json_connection::async_call") );
       fc::scoped_lock<fc::mutex> lock(my->_write_mutex);
       {
          *my->_out << "{\"id\":";
@@ -579,7 +579,7 @@ namespace fc { namespace rpc {
    future<variant> json_connection::async_call( const fc::string& method )
    {
       auto id = my->_next_id++;
-      my->_awaiting[id] = fc::promise<variant>::ptr( new fc::promise<variant>() );
+      my->_awaiting[id] = fc::promise<variant>::ptr( new fc::promise<variant>("json_connection::async_call") );
       fc::scoped_lock<fc::mutex> lock(my->_write_mutex);
       {
         *my->_out << "{\"id\":";
diff --git a/src/thread/task.cpp b/src/thread/task.cpp
index c3e1feb..b60ed25 100644
--- a/src/thread/task.cpp
+++ b/src/thread/task.cpp
@@ -15,6 +15,7 @@
 namespace fc {
   task_base::task_base(void* func)
   :
+  promise_base("task_base"),
   _posted_num(0),
   _active_context(nullptr),
   _next(nullptr),
diff --git a/src/thread/thread.cpp b/src/thread/thread.cpp
index aa00c65..260907e 100644
--- a/src/thread/thread.cpp
+++ b/src/thread/thread.cpp
@@ -71,7 +71,7 @@ namespace fc {
    }
 
    thread::thread( const std::string& name  ) {
-      promise<void>::ptr p(new promise<void>());
+      promise<void>::ptr p(new promise<void>("thread start"));
       boost::thread* t = new boost::thread( [this,p,name]() {
           try {
 		    set_thread_name(name.c_str()); // set thread's name for the debugger to display
@@ -277,8 +277,8 @@ namespace fc {
        return -1;
    }
 
-   void thread::async_task( task_base* t, const priority& p, const char* desc ) {
-      async_task( t, p, time_point::min(), desc );
+   void thread::async_task( task_base* t, const priority& p ) {
+      async_task( t, p, time_point::min() );
    }
 
    void thread::poke() {
@@ -286,10 +286,9 @@ namespace fc {
      my->task_ready.notify_one();
    }
 
-   void thread::async_task( task_base* t, const priority& p, const time_point& tp, const char* desc ) {
+   void thread::async_task( task_base* t, const priority& p, const time_point& tp ) {
       assert(my);
       t->_when = tp;
-      t->_desc = desc;
      // slog( "when %lld", t->_when.time_since_epoch().count() );
      // slog( "delay %lld", (tp - fc::time_point::now()).count() );
       task_base* stale_head = my->task_in_queue.load(boost::memory_order_relaxed);
diff --git a/src/thread/thread_d.hpp b/src/thread/thread_d.hpp
index 314e0a4..f533dd7 100644
--- a/src/thread/thread_d.hpp
+++ b/src/thread/thread_d.hpp
@@ -487,7 +487,7 @@ namespace fc {
 
          void unblock( fc::context* c ) {
              if(  fc::thread::current().my != this ) {
-               self.async( [=](){ unblock(c); } );
+               self.async( [=](){ unblock(c); }, "thread_d::unblock" );
                return;
              }
                if( c != current ) ready_push_front(c); 
diff --git a/tests/task_cancel.cpp b/tests/task_cancel.cpp
index e63544c..c0c76f6 100644
--- a/tests/task_cancel.cpp
+++ b/tests/task_cancel.cpp
@@ -19,7 +19,7 @@ BOOST_AUTO_TEST_CASE( cancel_an_active_task )
     {
       return sleep_aborted;
     }
-  });
+  }, "test_task");
 
   fc::time_point start_time = fc::time_point::now();
 
@@ -55,7 +55,7 @@ BOOST_AUTO_TEST_CASE( cleanup_cancelled_task )
     {
       BOOST_TEST_MESSAGE("Caught exception in async task, leaving the task's functor");
     }
-  });
+  }, "test_task");
   std::weak_ptr<std::string> weak_string_ptr(some_string);
   some_string.reset();
   BOOST_CHECK_MESSAGE(!weak_string_ptr.expired(), "Weak pointer should still be valid because async task should be holding the strong pointer");
@@ -75,18 +75,30 @@ BOOST_AUTO_TEST_CASE( cleanup_cancelled_task )
   BOOST_CHECK_MESSAGE(weak_string_ptr.expired(), "Weak pointer should now be invalid because async task should have been destroyed");
 }
 
+int task_execute_count = 0;
+fc::future<void> simple_task_done;
+void simple_task()
+{
+  task_execute_count++;
+  simple_task_done = fc::schedule([](){ simple_task(); }, 
+                                  fc::time_point::now() + fc::seconds(3),
+                                  "simple_task");
+}
+
 BOOST_AUTO_TEST_CASE( cancel_scheduled_task )
 {
   bool task_executed = false;
   try 
   {
-    auto result = fc::schedule( [&]() { task_executed = true; }, fc::time_point::now() + fc::seconds(3) );
-    result.cancel();
-    result.wait();
+    simple_task();
+    simple_task();
+    fc::usleep(fc::seconds(4));
+    simple_task_done.cancel();
+    simple_task_done.wait();
   } 
   catch ( const fc::exception& e )
   {
     wlog( "${e}", ("e",e.to_detail_string() ) );
   }
-  BOOST_CHECK(!task_executed);
+  BOOST_CHECK_EQUAL(task_execute_count, 2);
 }
\ No newline at end of file