Optimise BufferSet::attach_buffers code to avoid memory allocation in the RT thread and speed things up a bit.

git-svn-id: svn://localhost/ardour2/branches/3.0@8490 d708f5d6-7413-0410-9779-e7cbd77b26cf

libs/ardour/ardour/buffer_set.h

@@ -66,7 +66,8 @@ public:
 
 	void clear();
 
-	void attach_buffers(PortSet& ports, framecnt_t nframes, framecnt_t offset = 0);
+	void attach_buffers (PortSet& ports);
+	void get_jack_port_addresses (PortSet &, framecnt_t, framecnt_t);
 
 	/* the capacity here is a size_t and has a different interpretation depending
 	   on the DataType of the buffers. for audio, its a frame count. for MIDI

libs/ardour/ardour/io.h

@@ -42,6 +42,7 @@
 #include "ardour/session_object.h"
 #include "ardour/types.h"
 #include "ardour/utils.h"
+#include "ardour/buffer_set.h"
 
 class XMLNode;
 
@@ -50,7 +51,6 @@ namespace ARDOUR {
 class Amp;
 class AudioEngine;
 class AudioPort;
-class BufferSet;
 class Bundle;
 class MidiPort;
 class PeakMeter;
@@ -249,6 +249,8 @@ class IO : public SessionObject, public Latent
 
 	void setup_bundle ();
 	std::string bundle_channel_name (uint32_t, uint32_t, DataType) const;
+
+	BufferSet _buffers;
 };
 
 } // namespace ARDOUR

libs/ardour/buffer_set.cc

@@ -82,10 +82,12 @@ BufferSet::clear()
 #endif	
 }
 
-/** Make this BufferSet a direct mirror of a PortSet's buffers.
+/** Set up this BufferSet so that its data structures mirror a PortSet's buffers.
+ *  This is quite expensive and not RT-safe, so it should not be called in a process context;
+ *  get_jack_port_addresses() will fill in a structure set up by this method.
  */
 void
-BufferSet::attach_buffers (PortSet& ports, framecnt_t nframes, framecnt_t offset)
+BufferSet::attach_buffers (PortSet& ports)
 {
 	clear();
 
@@ -95,7 +97,7 @@ BufferSet::attach_buffers (PortSet& ports, framecnt_t nframes, framecnt_t offset
 
 		for (PortSet::iterator p = ports.begin(*t); p != ports.end(*t); ++p) {
 			assert(p->type() == *t);
-			v.push_back(&(p->get_buffer(nframes, offset)));
+			v.push_back (0);
 		}
 	}
 
@@ -105,6 +107,32 @@ BufferSet::attach_buffers (PortSet& ports, framecnt_t nframes, framecnt_t offset
 	_is_mirror = true;
 }
 
+/** Write the JACK port addresses from a PortSet into our data structures.  This
+ *  call assumes that attach_buffers() has already been called for the same PortSet.
+ *  Does not allocate, so RT-safe.
+ */
+void
+BufferSet::get_jack_port_addresses (PortSet& ports, framecnt_t nframes, framecnt_t offset)
+{
+	assert (_count == ports.count ());
+	assert (_available == ports.count ());
+	assert (_is_mirror);
+
+	assert (_buffers.size() == DataType::num_types);
+
+	for (DataType::iterator t = DataType::begin(); t != DataType::end(); ++t) {
+		BufferVec& v = _buffers[*t];
+
+		assert (v.size() == ports.num_ports (*t));
+
+		int i = 0;
+		for (PortSet::iterator p = ports.begin(*t); p != ports.end(*t); ++p) {
+			v[i] = &p->get_buffer (nframes, offset);
+			++i;
+		}
+	}
+}
+
 /** Ensure that there are @a num_buffers buffers of type @a type available,
  * each of size at least @a buffer_size
  */

libs/ardour/delivery.cc

@@ -246,7 +246,7 @@ Delivery::run (BufferSet& bufs, framepos_t start_frame, framepos_t end_frame, pf
 	   processing pathway that wants to use this->output_buffers() for some reason.
 	*/
 
-	output_buffers().attach_buffers (ports, nframes, _output_offset);
+	output_buffers().get_jack_port_addresses (ports, nframes, _output_offset);
 
 	// this Delivery processor is not a derived type, and thus we assume
 	// we really can modify the buffers passed in (it is almost certainly
@@ -544,6 +544,6 @@ Delivery::output_changed (IOChange change, void* /*src*/)
 {
 	if (change.type & IOChange::ConfigurationChanged) {
 		reset_panner ();
+		_output_buffers->attach_buffers (_output->ports ());
 	}
 }
-

libs/ardour/io.cc

@@ -447,6 +447,7 @@ IO::ensure_ports (ChanCount count, bool clear, void* src)
 		change.after = _ports.count ();
 		change.type = IOChange::ConfigurationChanged;
 		this->changed (change, src); /* EMIT SIGNAL */
+		_buffers.attach_buffers (_ports);
 		setup_bundle ();
 		_session.set_dirty ();
 	}
@@ -1522,12 +1523,10 @@ IO::connected_to (boost::shared_ptr<const IO> other) const
 void
 IO::process_input (boost::shared_ptr<Processor> proc, framepos_t start_frame, framepos_t end_frame, pframes_t nframes)
 {
-	BufferSet bufs;
-
 	/* don't read the data into new buffers - just use the port buffers directly */
 
-	bufs.attach_buffers (_ports, nframes, 0);
-	proc->run (bufs, start_frame, end_frame, nframes, true);
+	_buffers.get_jack_port_addresses (_ports, nframes, 0);
+	proc->run (_buffers, start_frame, end_frame, nframes, true);
 }
 
 void