slightly more efficient implementation of Graph::in_process_thread()
[ardour.git] / libs / ardour / graph.cc
index 9dfc611e1714512d112355e43f8205510a264fea..5b435884d4fe7d056248ba0d8f2b03275828b425 100644 (file)
@@ -222,17 +222,20 @@ Graph::prep()
         _finished_refcount = _init_finished_refcount[chain];
 
        /* Trigger the initial nodes for processing, which are the ones at the `input' end */
+       pthread_mutex_lock (&_trigger_mutex);
         for (i=_init_trigger_list[chain].begin(); i!=_init_trigger_list[chain].end(); i++) {
-                this->trigger( i->get() );
+               /* don't use ::trigger here, as we have already locked the mutex */
+                _trigger_queue.push_back (i->get ());
         }
+       pthread_mutex_unlock (&_trigger_mutex);
 }
 
 void
 Graph::trigger (GraphNode* n)
 {
-        pthread_mutex_lock (&_trigger_mutex);
+       pthread_mutex_lock (&_trigger_mutex);
         _trigger_queue.push_back (n);
-        pthread_mutex_unlock (&_trigger_mutex);
+       pthread_mutex_unlock (&_trigger_mutex);
 }
 
 /** Called when a node at the `output' end of the chain (ie one that has no-one to feed)
@@ -247,7 +250,7 @@ Graph::dec_ref()
                   the graph, so there is nothing more to do this time around.
                */
 
-                this->restart_cycle();
+               restart_cycle ();
         }
 }
 
@@ -266,7 +269,7 @@ Graph::restart_cycle()
                 return;
         }
 
-        this->prep();
+       prep ();
 
         if (_graph_empty) {
                 goto again;
@@ -276,41 +279,18 @@ Graph::restart_cycle()
         // starting with waking up the others.
 }
 
-static bool
-is_feedback (boost::shared_ptr<RouteList> routelist, Route* from, boost::shared_ptr<Route> to)
-{
-        for (RouteList::iterator ri=routelist->begin(); ri!=routelist->end(); ri++) {
-                if ((*ri).get() == from)
-                        return false;
-                if ((*ri) == to)
-                        return true;
-        }
-        assert(0);
-        return false;
-}
-
-static bool
-is_feedback (boost::shared_ptr<RouteList> routelist, boost::shared_ptr<Route> from, Route* to)
-{
-        for (RouteList::iterator ri=routelist->begin(); ri!=routelist->end(); ri++) {
-                if ((*ri).get() == to)
-                        return true;
-                if ((*ri) == from)
-                        return false;
-        }
-        assert(0);
-        return false;
-}
+/** Rechain our stuff using a list of routes (which can be in any order) and
+ *  a directed graph of their interconnections, which is guaranteed to be
+ *  acyclic.
+ */
 
 void
-Graph::rechain (boost::shared_ptr<RouteList> routelist)
+Graph::rechain (boost::shared_ptr<RouteList> routelist, GraphEdges const & edges)
 {
-        node_list_t::iterator ni;
         Glib::Mutex::Lock ls (_swap_mutex);
 
         int chain = _setup_chain;
         DEBUG_TRACE (DEBUG::Graph, string_compose ("============== setup %1\n", chain));
-        // set all refcounts to 0;
 
        /* This will become the number of nodes that do not feed any other node;
           once we have processed this number of those nodes, we have finished.
@@ -326,62 +306,47 @@ Graph::rechain (boost::shared_ptr<RouteList> routelist)
 
        /* Clear things out, and make _nodes_rt[chain] a copy of routelist */
         for (RouteList::iterator ri=routelist->begin(); ri!=routelist->end(); ri++) {
-                node_ptr_t n = boost::dynamic_pointer_cast<GraphNode> (*ri);
-
-                n->_init_refcount[chain] = 0;
-                n->_activation_set[chain].clear();
-                _nodes_rt[chain].push_back(n);
+                (*ri)->_init_refcount[chain] = 0;
+                (*ri)->_activation_set[chain].clear();
+                _nodes_rt[chain].push_back (*ri);
         }
 
         // now add refs for the connections.
 
-        for (ni=_nodes_rt[chain].begin(); ni!=_nodes_rt[chain].end(); ni++) {
-
-               /* We will set this to true if the node *ni is directly or
-                  indirectly fed by anything (without feedback)
-               */
-                bool has_input  = false;
-
-               /* We will set this to true if the node *ni directly feeds
-                  anything (without feedback)
-               */
-                bool has_output = false;
+        for (node_list_t::iterator ni = _nodes_rt[chain].begin(); ni != _nodes_rt[chain].end(); ni++) {
 
-               /* We will also set up *ni's _activation_set to contain any nodes
-                  that it directly feeds.
-               */
+                boost::shared_ptr<Route> r = boost::dynamic_pointer_cast<Route> (*ni);
 
-                boost::shared_ptr<Route> rp = boost::dynamic_pointer_cast<Route>( *ni);
+               /* The routes that are directly fed by r */
+               set<GraphVertex> fed_from_r = edges.from (r);
 
-                for (RouteList::iterator ri=routelist->begin(); ri!=routelist->end(); ri++) {
-                        if (rp->direct_feeds (*ri)) {
-                                if (is_feedback (routelist, rp.get(), *ri)) {
-                                        continue;
-                                }
+               /* Hence whether r has an output */
+               bool const has_output = !fed_from_r.empty ();
 
-                                has_output = true;
-                                (*ni)->_activation_set[chain].insert (boost::dynamic_pointer_cast<GraphNode> (*ri) );
-                        }
-                }
+               /* Set up r's activation set */
+               for (set<GraphVertex>::iterator i = fed_from_r.begin(); i != fed_from_r.end(); ++i) {
+                       r->_activation_set[chain].insert (*i);
+               }
 
-                for (Route::FedBy::iterator fi=rp->fed_by().begin(); fi!=rp->fed_by().end(); fi++) {
-                        if (boost::shared_ptr<Route> r = fi->r.lock()) {
-                                if (!is_feedback (routelist, r, rp.get())) {
-                                        has_input = true;
-                                }
-                        }
-                }
+               /* r has an input if there are some incoming edges to r in the graph */
+               bool const has_input = !edges.has_none_to (r);
 
                /* Increment the refcount of any route that we directly feed */
-                for (node_set_t::iterator ai=(*ni)->_activation_set[chain].begin(); ai!=(*ni)->_activation_set[chain].end(); ai++) {
+                for (node_set_t::iterator ai = r->_activation_set[chain].begin(); ai != r->_activation_set[chain].end(); ai++) {
                         (*ai)->_init_refcount[chain] += 1;
                 }
 
-                if (!has_input)
+                if (!has_input) {
+                       /* no input, so this node needs to be triggered initially to get things going */
                         _init_trigger_list[chain].push_back (*ni);
+               }
 
-                if (!has_output)
+                if (!has_output) {
+                       /* no output, so this is one of the nodes that we can count off to decide
+                          if we've finished
+                       */
                         _init_finished_refcount[chain] += 1;
+               }
         }
 
         _pending_chain = chain;
@@ -445,24 +410,6 @@ Graph::run_one()
         return false;
 }
 
-static void get_rt()
-{
-        if (!jack_is_realtime (AudioEngine::instance()->jack())) {
-                return;
-        }
-
-        int priority = jack_client_real_time_priority (AudioEngine::instance()->jack());
-
-        if (priority) {
-                struct sched_param rtparam;
-
-                memset (&rtparam, 0, sizeof (rtparam));
-                rtparam.sched_priority = priority;
-
-                pthread_setschedparam (pthread_self(), SCHED_FIFO, &rtparam);
-        }
-}
-
 void
 Graph::helper_thread()
 {
@@ -471,7 +418,6 @@ Graph::helper_thread()
        resume_rt_malloc_checks ();
 
         pt->get_buffers();
-        get_rt();
 
         while(1) {
                 if (run_one()) {
@@ -491,7 +437,6 @@ Graph::main_thread()
        resume_rt_malloc_checks ();
 
         pt->get_buffers();
-        get_rt();
 
   again:
         _callback_start_sem.wait ();
@@ -502,7 +447,7 @@ Graph::main_thread()
                 return;
         }
 
-        this->prep();
+       prep ();
 
         if (_graph_empty && !_quit_threads) {
                 _callback_done_sem.signal ();
@@ -652,10 +597,10 @@ Graph::process_one_route (Route* route)
 bool
 Graph::in_process_thread () const
 {
-       list<pthread_t>::const_iterator i = _thread_list.begin ();
-       while (i != _thread_list.end() && *i != pthread_self ()) {
-               ++i;
+       for (list<pthread_t>::const_iterator i = _thread_list.begin (); i != _thread_list.end(); ++i) {
+               if (*i == pthread_self()) {
+                       return true;
+               }
        }
-
-       return i != _thread_list.end ();
+       return false;
 }