8 files changed, 114 insertions, 55 deletions

diff --git a/libs/ardour/ardour/audio_backend.h b/libs/ardour/ardour/audio_backend.h
index 9052acd530..0e39625e8c 100644
--- a/libs/ardour/ardour/audio_backend.h
+++ b/libs/ardour/ardour/audio_backend.h
@@ -399,13 +399,25 @@ class AudioBackend : public PortEngine {
      * stacksize. The thread will begin executing @param func, and will exit
      * when that function returns.
      */
-    virtual int create_process_thread (boost::function<void()> func, AudioBackendNativeThread*, size_t stacksize) = 0;
+    virtual int create_process_thread (boost::function<void()> func) = 0;
 
-    /** Wait for the thread specified by @param thread to exit.
+    /** Wait for all processing threads to exit.
      * 
      * Return zero on success, non-zero on failure.
      */
-    virtual int wait_for_process_thread_exit (AudioBackendNativeThread thread) = 0;
+    virtual int join_process_threads () = 0;
+
+    /** Return true if execution context is in a backend thread
+     */
+    virtual bool in_process_thread () = 0;
+
+    /** Return the minimum stack size of audio threads in bytes
+     */
+    static size_t thread_stack_size () { return 100000; }
+
+    /** Return number of processing threads
+     */
+    virtual uint32_t process_thread_count () = 0;
 
     virtual void update_latencies () = 0;
 
diff --git a/libs/ardour/ardour/audioengine.h b/libs/ardour/ardour/audioengine.h
index 201d960479..1bf4be3243 100644
--- a/libs/ardour/ardour/audioengine.h
+++ b/libs/ardour/ardour/audioengine.h
@@ -100,8 +100,12 @@ public:
     pframes_t      sample_time_at_cycle_start ();
     pframes_t      samples_since_cycle_start ();
     bool           get_sync_offset (pframes_t& offset) const;
-    int            create_process_thread (boost::function<void()> func, AudioBackendNativeThread*, size_t stacksize);
-    int            wait_for_process_thread_exit (AudioBackendNativeThread);
+
+    int            create_process_thread (boost::function<void()> func);
+    int            join_process_threads ();
+    bool           in_process_thread ();
+    uint32_t       process_thread_count ();
+
     bool           is_realtime() const;
     bool           connected() const;
 
diff --git a/libs/ardour/ardour/graph.h b/libs/ardour/ardour/graph.h
index 08af6fb721..763723c792 100644
--- a/libs/ardour/ardour/graph.h
+++ b/libs/ardour/ardour/graph.h
@@ -31,8 +31,6 @@
 #include <glib.h>
 #include <cassert>
 
-#include <pthread.h>
-
 #include "pbd/semutils.h"
 
 #include "ardour/types.h"
@@ -59,8 +57,6 @@ class Graph : public SessionHandleRef
 public:
 	Graph (Session & session);
 
-	uint32_t threads_in_use () const { return _thread_list.size(); }
-
 	void prep();
 	void trigger (GraphNode * n);
 	void rechain (boost::shared_ptr<RouteList>, GraphEdges const &);
@@ -93,7 +89,6 @@ protected:
 	virtual void session_going_away ();
 
 private:
-	std::list<AudioBackendNativeThread> _thread_list;
 	volatile bool        _quit_threads;
 
 	void reset_thread_list ();
diff --git a/libs/ardour/ardour/types.h b/libs/ardour/ardour/types.h
index 526a71c58b..ee43d1f30f 100644
--- a/libs/ardour/ardour/types.h
+++ b/libs/ardour/ardour/types.h
@@ -615,16 +615,6 @@ namespace ARDOUR {
 	    uint32_t max; //< samples
 	};
 
-/* PLATFORM SPECIFIC #ifdef's here */
-
-	/** Define the native thread type used on the platform */
-	typedef pthread_t AudioBackendNativeThread;
-	static inline bool self_thread_equal (AudioBackendNativeThread thr) {
-		return pthread_equal (thr, pthread_self());
-	}
-
-/* PLATFORM SPECIFIC #endif's here */
-
 } // namespace ARDOUR
 
 
diff --git a/libs/ardour/audioengine.cc b/libs/ardour/audioengine.cc
index 465f88de56..631a861741 100644
--- a/libs/ardour/audioengine.cc
+++ b/libs/ardour/audioengine.cc
@@ -826,21 +826,39 @@ AudioEngine::get_sync_offset (pframes_t& offset) const
 }
 
 int
-AudioEngine::create_process_thread (boost::function<void()> func, AudioBackendNativeThread* thr, size_t stacksize)
+AudioEngine::create_process_thread (boost::function<void()> func)
 {
 	if (!_backend) {
 		return -1;
 	}
-	return _backend->create_process_thread (func, thr, stacksize);
+	return _backend->create_process_thread (func);
 }
 
 int
-AudioEngine::wait_for_process_thread_exit (AudioBackendNativeThread thr)
+AudioEngine::join_process_threads ()
+{
+	if (!_backend) {
+		return -1;
+	}
+	return _backend->join_process_threads ();
+}
+
+bool
+AudioEngine::in_process_thread ()
+{
+	if (!_backend) {
+		return false;
+	}
+	return _backend->in_process_thread ();
+}
+
+uint32_t
+AudioEngine::process_thread_count ()
 {
 	if (!_backend) {
 		return 0;
 	}
-	return _backend->wait_for_process_thread_exit (thr);
+	return _backend->process_thread_count ();
 }
 
 int
diff --git a/libs/ardour/graph.cc b/libs/ardour/graph.cc
index c8e374cddc..71eeee41ea 100644
--- a/libs/ardour/graph.cc
+++ b/libs/ardour/graph.cc
@@ -96,29 +96,24 @@ Graph::reset_thread_list ()
            number of threads.
         */
 
-        if (_thread_list.size() == num_threads) {
+        if (AudioEngine::instance()->process_thread_count() == num_threads) {
                 return;
         }
 
         Glib::Threads::Mutex::Lock lm (_session.engine().process_lock());
-	AudioBackendNativeThread a_thread;
 
-        if (!_thread_list.empty()) {
+        if (AudioEngine::instance()->process_thread_count() != 0) {
                 drop_threads ();
         }
 
-	if (AudioEngine::instance()->create_process_thread (boost::bind (&Graph::main_thread, this), &a_thread, 100000) != 0) {
+	if (AudioEngine::instance()->create_process_thread (boost::bind (&Graph::main_thread, this)) != 0) {
 		throw failed_constructor ();
 	}
 
-	_thread_list.push_back (a_thread);
-
         for (uint32_t i = 1; i < num_threads; ++i) {
-		if (AudioEngine::instance()->create_process_thread (boost::bind (&Graph::helper_thread, this), &a_thread, 100000) != 0) {
+		if (AudioEngine::instance()->create_process_thread (boost::bind (&Graph::helper_thread, this))) {
 			throw failed_constructor ();
 		}
-		
-		_thread_list.push_back (a_thread);
         }
 }
 
@@ -140,17 +135,15 @@ Graph::drop_threads ()
 {
         _quit_threads = true;
 
-        for (unsigned int i=0; i< _thread_list.size(); i++) {
+        uint32_t thread_count = AudioEngine::instance()->process_thread_count ();
+
+        for (unsigned int i=0; i < thread_count; i++) {
 		_execution_sem.signal ();
         }
 
         _callback_start_sem.signal ();
 
-        for (list<AudioBackendNativeThread>::iterator i = _thread_list.begin(); i != _thread_list.end(); ++i) {
-		AudioEngine::instance()->wait_for_process_thread_exit (*i);
-        }
-
-        _thread_list.clear ();
+	AudioEngine::instance()->join_process_threads ();
 
 	_execution_tokens = 0;
 
@@ -583,10 +576,5 @@ Graph::process_one_route (Route* route)
 bool
 Graph::in_process_thread () const
 {
-	for (list<AudioBackendNativeThread>::const_iterator i = _thread_list.begin (); i != _thread_list.end(); ++i) {
-		if (self_thread_equal (*i)) {
-			return true;
-		}
-	}
-	return false;
+	return AudioEngine::instance()->in_process_thread ();
 }
diff --git a/libs/backends/jack/jack_audiobackend.cc b/libs/backends/jack/jack_audiobackend.cc
index c6a523f4d2..a651f2522d 100644
--- a/libs/backends/jack/jack_audiobackend.cc
+++ b/libs/backends/jack/jack_audiobackend.cc
@@ -45,6 +45,7 @@ using namespace PBD;
 using std::string;
 using std::vector;
 
+
 #define GET_PRIVATE_JACK_POINTER(localvar)  jack_client_t* localvar = _jack_connection->jack(); if (!(localvar)) { return; }
 #define GET_PRIVATE_JACK_POINTER_RET(localvar,r) jack_client_t* localvar = _jack_connection->jack(); if (!(localvar)) { return r; }
 
@@ -825,25 +826,72 @@ JACKAudioBackend::_latency_callback (jack_latency_callback_mode_t mode, void* ar
 }
 
 int
-JACKAudioBackend::create_process_thread (boost::function<void()> f, pthread_t* thread, size_t stacksize)
+JACKAudioBackend::create_process_thread (boost::function<void()> f)
 {
         GET_PRIVATE_JACK_POINTER_RET (_priv_jack, -1);
-        ThreadData* td = new ThreadData (this, f, stacksize);
 
-        if (jack_client_create_thread (_priv_jack, thread, jack_client_real_time_priority (_priv_jack),
+	jack_native_thread_t thread_id;
+        ThreadData* td = new ThreadData (this, f, thread_stack_size());
+
+        if (jack_client_create_thread (_priv_jack, &thread_id, jack_client_real_time_priority (_priv_jack),
                                        jack_is_realtime (_priv_jack), _start_process_thread, td)) {
                 return -1;
         }
 
-        return 0;
+	_jack_threads.push_back(thread_id);
+	return 0;
 }
 
 int
-JACKAudioBackend::wait_for_process_thread_exit (AudioBackendNativeThread thr)
+JACKAudioBackend::join_process_threads ()
+{
+        GET_PRIVATE_JACK_POINTER_RET (_priv_jack, -1);
+
+	int ret = 0;
+
+	for (std::vector<jack_native_thread_t>::const_iterator i = _jack_threads.begin ();
+	     i != _jack_threads.end(); i++) {
+
+#if defined(USING_JACK2_EXPANSION_OF_JACK_API) || defined(PLATFORM_WINDOWS)
+		if (jack_client_stop_thread (_priv_jack, *i) != 0) {
+#else
+		void* status;
+		if (pthread_join (*i, &status) != 0) {
+#endif
+			error << "AudioEngine: cannot stop process thread" << endmsg;
+			ret += -1;
+		}
+	}
+
+	_jack_threads.clear();
+
+	return ret;
+}
+
+bool
+JACKAudioBackend::in_process_thread ()
+{
+	for (std::vector<jack_native_thread_t>::const_iterator i = _jack_threads.begin ();
+	     i != _jack_threads.end(); i++) {
+
+#ifdef COMPILER_MINGW
+		if (*i == GetCurrentThread()) {
+			return true;
+		}
+#else // pthreads
+		if (pthread_equal (*i, pthread_self()) != 0) {
+			return true;
+		}
+#endif
+	}
+
+	return false;
+}
+
+uint32_t
+JACKAudioBackend::process_thread_count ()
 {
-	void* status;
-	/* this doesn't actively try to stop the thread, it just waits till it exits */
-	return pthread_join (thr, &status);
+	return _jack_threads.size();
 }
 
 void*
diff --git a/libs/backends/jack/jack_audiobackend.h b/libs/backends/jack/jack_audiobackend.h
index 9ab545f3ee..b8d8b3b3f1 100644
--- a/libs/backends/jack/jack_audiobackend.h
+++ b/libs/backends/jack/jack_audiobackend.h
@@ -103,8 +103,10 @@ class JACKAudioBackend : public AudioBackend {
 
     size_t raw_buffer_size (DataType t);
 
-    int create_process_thread (boost::function<void()> func, AudioBackendNativeThread*, size_t stacksize);
-    int wait_for_process_thread_exit (AudioBackendNativeThread);
+    int create_process_thread (boost::function<void()> func);
+    int join_process_threads ();
+    bool in_process_thread ();
+    uint32_t process_thread_count ();
 
     void transport_start ();
     void transport_stop ();
@@ -184,6 +186,8 @@ class JACKAudioBackend : public AudioBackend {
     bool            _freewheeling;
     std::map<DataType,size_t> _raw_buffer_sizes;
 
+    std::vector<jack_native_thread_t> _jack_threads;
+
     static int  _xrun_callback (void *arg);
     static void* _process_thread (void *arg);
     static int  _sample_rate_callback (pframes_t nframes, void *arg);