some modifications -> wqueue loop

include/boost/fiber/algorithm.hpp

@@ -29,8 +29,6 @@ namespace fibers {
 
 struct BOOST_FIBERS_DECL algorithm : private noncopyable
 {
-    virtual void spawn( detail::fiber_base::ptr_t const&) = 0;
-
     virtual void priority( detail::fiber_base::ptr_t const&, int) = 0;
 
     virtual void join( detail::fiber_base::ptr_t const&) = 0;

include/boost/fiber/detail/fiber_base.hpp

@@ -176,6 +176,17 @@ public:
             flags_ &= ~flag_interruption_requested;
     }
 
+    bool wake_up() const BOOST_NOEXCEPT
+    { return 0 != ( flags_ & flag_wake_up); }
+
+    void wake_up( bool req) BOOST_NOEXCEPT
+    {
+        if ( req)
+            flags_ |= flag_wake_up;
+        else
+            flags_ &= ~flag_wake_up;
+    }
+
     bool is_terminated() const BOOST_NOEXCEPT
     { return state_terminated == state_; }
 
@@ -228,7 +239,7 @@ public:
     }
 #endif
         state_t previous = state_.exchange( state_ready, memory_order_seq_cst);
-        BOOST_ASSERT( state_waiting == previous || state_running == previous);
+        BOOST_ASSERT( state_waiting == previous || state_running == previous || state_ready == previous);
     }
 
     void set_running() BOOST_NOEXCEPT

include/boost/fiber/detail/flags.hpp

@@ -25,7 +25,8 @@ enum flag_t
     flag_unwind_stack           = 1 << 2,
     flag_preserve_fpu           = 1 << 3,
     flag_interruption_blocked   = 1 << 4,
-    flag_interruption_requested = 1 << 5
+    flag_interruption_requested = 1 << 5,
+    flag_wake_up                = 1 << 6
 };
 
 }}}

include/boost/fiber/round_robin.hpp

@@ -49,8 +49,6 @@ public:
 
     ~round_robin() BOOST_NOEXCEPT;
 
-    void spawn( detail::fiber_base::ptr_t const&);
-
     void priority( detail::fiber_base::ptr_t const&, int);
 
     void join( detail::fiber_base::ptr_t const&);

src/detail/fiber_base.cpp

@@ -61,10 +61,7 @@ fiber_base::release()
     unique_lock< spinlock > lk( joining_mtx_);
     BOOST_FOREACH( fiber_base::ptr_t & p, joining_)
     {
-        // active fiber migth join this fiber
-        // therefore do not set to state_ready
-        if ( ! p->is_running() )
-            p->set_ready();
+        p->wake_up( true);
     }
 }
 

src/round_robin.cpp

@@ -54,90 +54,30 @@ round_robin::~round_robin()
 #endif
 }
 
-void
-round_robin::spawn( detail::fiber_base::ptr_t const& f)
-{
-    BOOST_ASSERT( f);
-    BOOST_ASSERT( ! f->is_terminated() );
-    BOOST_ASSERT( f != active_fiber_);
-
-    detail::fiber_base::ptr_t tmp = active_fiber_;
-    try
-    {
-        active_fiber_ = f;
-        active_fiber_->set_running();
-        active_fiber_->resume();
-        // after return from fiber::resume() the fiber is:
-        // ready      -> already in requeue_
-        // waiting    -> already in wqueue_
-        // terminated -> not stored in round_robin/will be deleted
-        //               call terminate() in order to release
-        //               joining fibers
-        if ( f->is_terminated() )
-            f->release();
-    }
-    catch (...)
-    {
-        active_fiber_ = tmp;
-        throw;
-    }
-    active_fiber_ = tmp;
-}
-
 bool
 round_robin::run()
 {
-#if 0
-    // stable-sort has n*log(n) complexity if n*log(n) extra space is available
-    std::size_t n = wqueue_.size();
-    if ( 1 < n)
-    {
-        std::size_t new_capacity = n * std::log10( n) + n;
-        if ( wqueue_.capacity() < new_capacity)
-            wqueue_.reserve( new_capacity);
-
-        // sort wqueue_ depending on state
-        wqueue_.sort();
-    }
-
-    // check which waiting fiber should be interrupted
-    // make it ready and add it to rqueue_
-    std::pair< wqueue_t::iterator, wqueue_t::iterator > p =
-            wqueue_.equal_range( detail::state_waiting);
-    for ( wqueue_t::iterator i = p.first; i != p.second; ++i)
-    {
-        if ( ( * i)->interruption_requested() )
-            ( * i)->set_ready();
-    }
-
-    // copy all ready fibers to rqueue_
-    // and remove fibers from wqueue_
-    p = wqueue_.equal_range( detail::state_ready);
-    if ( p.first != p.second)
-    {
-        unique_lock< detail::spinlock > lk( rqueue_mtx_);
-        rqueue_.insert( rqueue_.end(), p.first, p.second);
-        lk.unlock();
-        wqueue_.erase( p.first, p.second);
-    }
-#endif
+    // loop over waiting queue
     wqueue_t wqueue;
     BOOST_FOREACH( detail::fiber_base::ptr_t const& f, wqueue_)
     {
-        if ( f->interruption_requested() && ! f->is_ready() )
-            f->set_ready();
-        if ( f->is_ready() )
+        // set fiber to state_ready if interruption was requested
+        if ( f->interruption_requested() || f->wake_up() || f->is_ready() )
         {
+            f->wake_up( false);
+            f->set_ready();
             unique_lock< detail::spinlock > lk( rqueue_mtx_);
             rqueue_.push_back( f);
         }
         else
+        // otherwise in the local waiting queue
             wqueue.push_back( f);
     }
+    // exchange local with global waiting queue
     wqueue_.swap( wqueue);
 
-    // pop new fiber from runnable-queue which is not complete
-    // (example: fiber in runnable-queue could be canceled by active-fiber)
+    // pop new fiber from ready-queue which is not complete
+    // (example: fiber in ready-queue could be canceled by active-fiber)
     detail::fiber_base::ptr_t f;
     do
     {