libs/ardour/graph.cc

   1 /*
   2   Copyright (C) 2010 Paul Davis
   3   Author: Torben Hohn
   4
   5   This program is free software; you can redistribute it and/or modify
   6   it under the terms of the GNU General Public License as published by
   7   the Free Software Foundation; either version 2 of the License, or
   8   (at your option) any later version.
   9
  10   This program is distributed in the hope that it will be useful,
  11   but WITHOUT ANY WARRANTY; without even the implied warranty of
  12   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13   GNU General Public License for more details.
  14
  15   You should have received a copy of the GNU General Public License
  16   along with this program; if not, write to the Free Software
  17   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  18
  19 */
  20 #include <stdio.h>
  21 #include <cmath>
  22
  23 #include "pbd/compose.h"
  24 #include "pbd/debug_rt_alloc.h"
  25
  26 #include "ardour/debug.h"
  27 #include "ardour/graph.h"
  28 #include "ardour/types.h"
  29 #include "ardour/session.h"
  30 #include "ardour/route.h"
  31 #include "ardour/process_thread.h"
  32 #include "ardour/audioengine.h"
  33
  34 #include <jack/thread.h>
  35
  36 #include "i18n.h"
  37
  38 using namespace ARDOUR;
  39 using namespace PBD;
  40 using namespace std;
  41
  42 #ifdef DEBUG_RT_ALLOC
  43 static Graph* graph = 0;
  44
  45 extern "C" {
  46
  47 int alloc_allowed ()
  48 {
  49         return !graph->in_process_thread ();
  50 }
  51
  52 }
  53 #endif
  54
  55 Graph::Graph (Session & session)
  56         : SessionHandleRef (session)
  57         , _quit_threads (false)
  58         , _execution_sem ("graph_execution", 0)
  59         , _callback_start_sem ("graph_start", 0)
  60         , _callback_done_sem ("graph_done", 0)
  61         , _cleanup_sem ("graph_cleanup", 0)
  62 {
  63         pthread_mutex_init( &_trigger_mutex, NULL);
  64
  65         /* XXX: rather hacky `fix' to stop _trigger_queue.push_back() allocating
  66            memory in the RT thread.
  67         */
  68         _trigger_queue.reserve (8192);
  69
  70         _execution_tokens = 0;
  71
  72         _current_chain = 0;
  73         _pending_chain = 0;
  74         _setup_chain   = 1;
  75         _quit_threads = false;
  76         _graph_empty = true;
  77
  78         reset_thread_list ();
  79
  80         Config->ParameterChanged.connect_same_thread (processor_usage_connection, boost::bind (&Graph::parameter_changed, this, _1));
  81
  82 #ifdef DEBUG_RT_ALLOC
  83         graph = this;
  84         pbd_alloc_allowed = &::alloc_allowed;
  85 #endif
  86 }
  87
  88 void
  89 Graph::parameter_changed (std::string param)
  90 {
  91         if (param == X_("processor-usage")) {
  92                 reset_thread_list ();
  93         }
  94 }
  95
  96 /** Set up threads for running the graph */
  97 void
  98 Graph::reset_thread_list ()
  99 {
 100         uint32_t num_threads = how_many_dsp_threads ();
 101
 102         /* don't bother doing anything here if we already have the right
 103            number of threads.
 104         */
 105
 106         if (_thread_list.size() == num_threads) {
 107                 return;
 108         }
 109
 110         Glib::Mutex::Lock lm (_session.engine().process_lock());
 111         pthread_t a_thread;
 112
 113         if (!_thread_list.empty()) {
 114                 drop_threads ();
 115         }
 116
 117 #if 0
 118         /* XXX this only makes sense when we can use just the AudioEngine thread
 119            and still keep the graph current with the route list
 120         */
 121         if (num_threads <= 1) {
 122                 /* no point creating 1 thread - the AudioEngine already gives us one
 123                  */
 124                 return;
 125         }
 126 #endif
 127         if (AudioEngine::instance()->create_process_thread (boost::bind (&Graph::main_thread, this), &a_thread, 100000) == 0) {
 128                 _thread_list.push_back (a_thread);
 129         }
 130
 131         for (uint32_t i = 1; i < num_threads; ++i) {
 132                 if (AudioEngine::instance()->create_process_thread (boost::bind (&Graph::helper_thread, this), &a_thread, 100000) == 0) {
 133                         _thread_list.push_back (a_thread);
 134                 }
 135         }
 136 }
 137
 138 void
 139 Graph::session_going_away()
 140 {
 141         drop_threads ();
 142
 143         // now drop all references on the nodes.
 144         _nodes_rt[0].clear();
 145         _nodes_rt[1].clear();
 146         _init_trigger_list[0].clear();
 147         _init_trigger_list[1].clear();
 148         _trigger_queue.clear();
 149 }
 150
 151 void
 152 Graph::drop_threads ()
 153 {
 154         _quit_threads = true;
 155
 156         for (unsigned int i=0; i< _thread_list.size(); i++) {
 157                 _execution_sem.signal ();
 158         }
 159
 160         _callback_start_sem.signal ();
 161
 162         for (list<pthread_t>::iterator i = _thread_list.begin(); i != _thread_list.end(); ++i) {
 163                 void* status;
 164                 pthread_join (*i, &status);
 165         }
 166
 167         _thread_list.clear ();
 168
 169         _execution_tokens = 0;
 170
 171         _quit_threads = false;
 172 }
 173
 174 void
 175 Graph::clear_other_chain ()
 176 {
 177         Glib::Mutex::Lock ls (_swap_mutex);
 178
 179         while (1) {
 180                 if (_setup_chain != _pending_chain) {
 181
 182                         for (node_list_t::iterator ni=_nodes_rt[_setup_chain].begin(); ni!=_nodes_rt[_setup_chain].end(); ni++) {
 183                                 (*ni)->_activation_set[_setup_chain].clear();
 184                         }
 185
 186                         _nodes_rt[_setup_chain].clear ();
 187                         _init_trigger_list[_setup_chain].clear ();
 188                         break;
 189                 }
 190                 /* setup chain == pending chain - we have
 191                    to wait till this is no longer true.
 192                 */
 193                 _cleanup_cond.wait (_swap_mutex);
 194         }
 195 }
 196
 197 void
 198 Graph::prep()
 199 {
 200         node_list_t::iterator i;
 201         int chain;
 202
 203         if (_swap_mutex.trylock()) {
 204                 // we got the swap mutex.
 205                 if (_current_chain != _pending_chain)
 206                 {
 207                         // printf ("chain swap ! %d -> %d\n", _current_chain, _pending_chain);
 208                         _setup_chain = _current_chain;
 209                         _current_chain = _pending_chain;
 210                         _cleanup_cond.signal ();
 211                 }
 212                 _swap_mutex.unlock ();
 213         }
 214
 215         chain = _current_chain;
 216
 217         _graph_empty = true;
 218         for (i=_nodes_rt[chain].begin(); i!=_nodes_rt[chain].end(); i++) {
 219                 (*i)->prep( chain);
 220                 _graph_empty = false;
 221         }
 222         _finished_refcount = _init_finished_refcount[chain];
 223
 224         /* Trigger the initial nodes for processing, which are the ones at the `input' end */
 225         for (i=_init_trigger_list[chain].begin(); i!=_init_trigger_list[chain].end(); i++) {
 226                 trigger (i->get ());
 227         }
 228 }
 229
 230 void
 231 Graph::trigger (GraphNode* n)
 232 {
 233         pthread_mutex_lock (&_trigger_mutex);
 234         _trigger_queue.push_back (n);
 235         pthread_mutex_unlock (&_trigger_mutex);
 236 }
 237
 238 /** Called when a node at the `output' end of the chain (ie one that has no-one to feed)
 239  *  is finished.
 240  */
 241 void
 242 Graph::dec_ref()
 243 {
 244         if (g_atomic_int_dec_and_test (&_finished_refcount)) {
 245
 246                 /* We have run all the nodes that are at the `output' end of
 247                    the graph, so there is nothing more to do this time around.
 248                 */
 249
 250                 restart_cycle ();
 251         }
 252 }
 253
 254 void
 255 Graph::restart_cycle()
 256 {
 257         // we are through. wakeup our caller.
 258
 259   again:
 260         _callback_done_sem.signal ();
 261
 262         /* Block until the a process callback triggers us */
 263         _callback_start_sem.wait();
 264
 265         if (_quit_threads) {
 266                 return;
 267         }
 268
 269         prep ();
 270
 271         if (_graph_empty) {
 272                 goto again;
 273         }
 274
 275         // returning will restart the cycle.
 276         // starting with waking up the others.
 277 }
 278
 279 static bool
 280 is_feedback (boost::shared_ptr<RouteList> routelist, Route* from, boost::shared_ptr<Route> to)
 281 {
 282         for (RouteList::iterator ri=routelist->begin(); ri!=routelist->end(); ri++) {
 283                 if ((*ri).get() == from) {
 284                         return false;
 285                 }
 286                 if ((*ri) == to) {
 287                         return true;
 288                 }
 289         }
 290
 291         return false;
 292 }
 293
 294 static bool
 295 is_feedback (boost::shared_ptr<RouteList> routelist, boost::shared_ptr<Route> from, Route* to)
 296 {
 297         for (RouteList::iterator ri=routelist->begin(); ri!=routelist->end(); ri++) {
 298                 if ((*ri).get() == to) {
 299                         return true;
 300                 }
 301                 if ((*ri) == from) {
 302                         return false;
 303                 }
 304         }
 305
 306         return false;
 307 }
 308
 309 void
 310 Graph::rechain (boost::shared_ptr<RouteList> routelist)
 311 {
 312         node_list_t::iterator ni;
 313         Glib::Mutex::Lock ls (_swap_mutex);
 314
 315         int chain = _setup_chain;
 316         DEBUG_TRACE (DEBUG::Graph, string_compose ("============== setup %1\n", chain));
 317         // set all refcounts to 0;
 318
 319         /* This will become the number of nodes that do not feed any other node;
 320            once we have processed this number of those nodes, we have finished.
 321         */
 322         _init_finished_refcount[chain] = 0;
 323
 324         /* This will become a list of nodes that are not fed by another node, ie
 325            those at the `input' end.
 326         */
 327         _init_trigger_list[chain].clear();
 328
 329         _nodes_rt[chain].clear();
 330
 331         /* Clear things out, and make _nodes_rt[chain] a copy of routelist */
 332         for (RouteList::iterator ri=routelist->begin(); ri!=routelist->end(); ri++) {
 333                 node_ptr_t n = boost::dynamic_pointer_cast<GraphNode> (*ri);
 334
 335                 n->_init_refcount[chain] = 0;
 336                 n->_activation_set[chain].clear();
 337                 _nodes_rt[chain].push_back(n);
 338         }
 339
 340         // now add refs for the connections.
 341
 342         for (ni=_nodes_rt[chain].begin(); ni!=_nodes_rt[chain].end(); ni++) {
 343
 344                 /* We will set this to true if the node *ni is directly or
 345                    indirectly fed by anything (without feedback)
 346                 */
 347                 bool has_input  = false;
 348
 349                 /* We will set this to true if the node *ni directly feeds
 350                    anything (without feedback)
 351                 */
 352                 bool has_output = false;
 353
 354                 /* We will also set up *ni's _activation_set to contain any nodes
 355                    that it directly feeds.
 356                 */
 357
 358                 boost::shared_ptr<Route> rp = boost::dynamic_pointer_cast<Route>( *ni);
 359
 360                 for (RouteList::iterator ri=routelist->begin(); ri!=routelist->end(); ri++) {
 361                         if (rp->direct_feeds (*ri)) {
 362                                 if (is_feedback (routelist, rp.get(), *ri)) {
 363                                         continue;
 364                                 }
 365
 366                                 has_output = true;
 367                                 (*ni)->_activation_set[chain].insert (boost::dynamic_pointer_cast<GraphNode> (*ri) );
 368                         }
 369                 }
 370
 371                 for (Route::FedBy::iterator fi=rp->fed_by().begin(); fi!=rp->fed_by().end(); fi++) {
 372                         if (boost::shared_ptr<Route> r = fi->r.lock()) {
 373                                 if (!is_feedback (routelist, r, rp.get())) {
 374                                         has_input = true;
 375                                 }
 376                         }
 377                 }
 378
 379                 /* Increment the refcount of any route that we directly feed */
 380                 for (node_set_t::iterator ai=(*ni)->_activation_set[chain].begin(); ai!=(*ni)->_activation_set[chain].end(); ai++) {
 381                         (*ai)->_init_refcount[chain] += 1;
 382                 }
 383
 384                 if (!has_input) {
 385                         _init_trigger_list[chain].push_back (*ni);
 386                 }
 387
 388                 if (!has_output) {
 389                         _init_finished_refcount[chain] += 1;
 390                 }
 391         }
 392
 393         _pending_chain = chain;
 394         dump(chain);
 395 }
 396
 397 /** Called by both the main thread and all helpers.
 398  *  @return true to quit, false to carry on.
 399  */
 400 bool
 401 Graph::run_one()
 402 {
 403         GraphNode* to_run;
 404
 405         pthread_mutex_lock (&_trigger_mutex);
 406         if (_trigger_queue.size()) {
 407                 to_run = _trigger_queue.back();
 408                 _trigger_queue.pop_back();
 409         } else {
 410                 to_run = 0;
 411         }
 412
 413         /* the number of threads that are asleep */
 414         int et = _execution_tokens;
 415         /* the number of nodes that need to be run */
 416         int ts = _trigger_queue.size();
 417
 418         /* hence how many threads to wake up */
 419         int wakeup = min (et, ts);
 420         /* update the number of threads that will still be sleeping */
 421         _execution_tokens -= wakeup;
 422
 423         DEBUG_TRACE(DEBUG::ProcessThreads, string_compose ("%1 signals %2\n", pthread_self(), wakeup));
 424
 425         for (int i = 0; i < wakeup; i++) {
 426                 _execution_sem.signal ();
 427         }
 428
 429         while (to_run == 0) {
 430                 _execution_tokens += 1;
 431                 pthread_mutex_unlock (&_trigger_mutex);
 432                 DEBUG_TRACE (DEBUG::ProcessThreads, string_compose ("%1 goes to sleep\n", pthread_self()));
 433                 _execution_sem.wait ();
 434                 if (_quit_threads) {
 435                         return true;
 436                 }
 437                 DEBUG_TRACE (DEBUG::ProcessThreads, string_compose ("%1 is awake\n", pthread_self()));
 438                 pthread_mutex_lock (&_trigger_mutex);
 439                 if (_trigger_queue.size()) {
 440                         to_run = _trigger_queue.back();
 441                         _trigger_queue.pop_back();
 442                 }
 443         }
 444         pthread_mutex_unlock (&_trigger_mutex);
 445
 446         to_run->process();
 447         to_run->finish (_current_chain);
 448
 449         DEBUG_TRACE(DEBUG::ProcessThreads, string_compose ("%1 has finished run_one()\n", pthread_self()));
 450
 451         return false;
 452 }
 453
 454 static void get_rt()
 455 {
 456         if (!jack_is_realtime (AudioEngine::instance()->jack())) {
 457                 return;
 458         }
 459
 460         int priority = jack_client_real_time_priority (AudioEngine::instance()->jack());
 461
 462         if (priority) {
 463                 struct sched_param rtparam;
 464
 465                 memset (&rtparam, 0, sizeof (rtparam));
 466                 rtparam.sched_priority = priority;
 467
 468                 pthread_setschedparam (pthread_self(), SCHED_FIFO, &rtparam);
 469         }
 470 }
 471
 472 void
 473 Graph::helper_thread()
 474 {
 475         suspend_rt_malloc_checks ();
 476         ProcessThread* pt = new ProcessThread ();
 477         resume_rt_malloc_checks ();
 478
 479         pt->get_buffers();
 480         get_rt();
 481
 482         while(1) {
 483                 if (run_one()) {
 484                         break;
 485                 }
 486         }
 487
 488         pt->drop_buffers();
 489 }
 490
 491 /** Here's the main graph thread */
 492 void
 493 Graph::main_thread()
 494 {
 495         suspend_rt_malloc_checks ();
 496         ProcessThread* pt = new ProcessThread ();
 497         resume_rt_malloc_checks ();
 498
 499         pt->get_buffers();
 500         get_rt();
 501
 502   again:
 503         _callback_start_sem.wait ();
 504
 505         DEBUG_TRACE(DEBUG::ProcessThreads, "main thread is awake\n");
 506
 507         if (_quit_threads) {
 508                 return;
 509         }
 510
 511         prep ();
 512
 513         if (_graph_empty && !_quit_threads) {
 514                 _callback_done_sem.signal ();
 515                 DEBUG_TRACE(DEBUG::ProcessThreads, "main thread sees graph done, goes back to sleep\n");
 516                 goto again;
 517         }
 518
 519         /* This loop will run forever */
 520         while (1) {
 521                 DEBUG_TRACE(DEBUG::ProcessThreads, "main thread runs one graph node\n");
 522                 if (run_one()) {
 523                         break;
 524                 }
 525         }
 526
 527         pt->drop_buffers();
 528 }
 529
 530 void
 531 Graph::dump (int chain)
 532 {
 533 #ifndef NDEBUG
 534         node_list_t::iterator ni;
 535         node_set_t::iterator ai;
 536
 537         chain = _pending_chain;
 538
 539         DEBUG_TRACE (DEBUG::Graph, "--------------------------------------------Graph dump:\n");
 540         for (ni=_nodes_rt[chain].begin(); ni!=_nodes_rt[chain].end(); ni++) {
 541                 boost::shared_ptr<Route> rp = boost::dynamic_pointer_cast<Route>( *ni);
 542                 DEBUG_TRACE (DEBUG::Graph, string_compose ("GraphNode: %1  refcount: %2\n", rp->name().c_str(), (*ni)->_init_refcount[chain]));
 543                 for (ai=(*ni)->_activation_set[chain].begin(); ai!=(*ni)->_activation_set[chain].end(); ai++) {
 544                         DEBUG_TRACE (DEBUG::Graph, string_compose ("  triggers: %1\n", boost::dynamic_pointer_cast<Route>(*ai)->name().c_str()));
 545                 }
 546         }
 547
 548         DEBUG_TRACE (DEBUG::Graph, "------------- trigger list:\n");
 549         for (ni=_init_trigger_list[chain].begin(); ni!=_init_trigger_list[chain].end(); ni++) {
 550                 DEBUG_TRACE (DEBUG::Graph, string_compose ("GraphNode: %1  refcount: %2\n", boost::dynamic_pointer_cast<Route>(*ni)->name().c_str(), (*ni)->_init_refcount[chain]));
 551         }
 552
 553         DEBUG_TRACE (DEBUG::Graph, string_compose ("final activation refcount: %1\n", _init_finished_refcount[chain]));
 554 #endif
 555 }
 556
 557 int
 558 Graph::silent_process_routes (pframes_t nframes, framepos_t start_frame, framepos_t end_frame, bool& need_butler)
 559 {
 560         _process_nframes = nframes;
 561         _process_start_frame = start_frame;
 562         _process_end_frame = end_frame;
 563
 564         _process_silent = true;
 565         _process_noroll = false;
 566         _process_retval = 0;
 567         _process_need_butler = false;
 568
 569         if (!_graph_empty) {
 570                 DEBUG_TRACE(DEBUG::ProcessThreads, "wake graph for silent process\n");
 571                 _callback_start_sem.signal ();
 572                 _callback_done_sem.wait ();
 573         }
 574
 575         need_butler = _process_need_butler;
 576
 577         return _process_retval;
 578 }
 579
 580 int
 581 Graph::process_routes (pframes_t nframes, framepos_t start_frame, framepos_t end_frame, int declick, bool& need_butler)
 582 {
 583         DEBUG_TRACE (DEBUG::ProcessThreads, string_compose ("graph execution from %1 to %2 = %3\n", start_frame, end_frame, nframes));
 584
 585         _process_nframes = nframes;
 586         _process_start_frame = start_frame;
 587         _process_end_frame = end_frame;
 588         _process_declick = declick;
 589
 590         _process_silent = false;
 591         _process_noroll = false;
 592         _process_retval = 0;
 593         _process_need_butler = false;
 594
 595         DEBUG_TRACE(DEBUG::ProcessThreads, "wake graph for non-silent process\n");
 596         _callback_start_sem.signal ();
 597         _callback_done_sem.wait ();
 598
 599         DEBUG_TRACE (DEBUG::ProcessThreads, "graph execution complete\n");
 600
 601         need_butler = _process_need_butler;
 602
 603         return _process_retval;
 604 }
 605
 606 int
 607 Graph::routes_no_roll (pframes_t nframes, framepos_t start_frame, framepos_t end_frame,
 608                        bool non_rt_pending, int declick)
 609 {
 610         DEBUG_TRACE (DEBUG::ProcessThreads, string_compose ("no-roll graph execution from %1 to %2 = %3\n", start_frame, end_frame, nframes));
 611
 612         _process_nframes = nframes;
 613         _process_start_frame = start_frame;
 614         _process_end_frame = end_frame;
 615         _process_declick = declick;
 616         _process_non_rt_pending = non_rt_pending;
 617
 618         _process_silent = false;
 619         _process_noroll = true;
 620         _process_retval = 0;
 621         _process_need_butler = false;
 622
 623         DEBUG_TRACE(DEBUG::ProcessThreads, "wake graph for no-roll process\n");
 624         _callback_start_sem.signal ();
 625         _callback_done_sem.wait ();
 626
 627         return _process_retval;
 628 }
 629 void
 630 Graph::process_one_route (Route* route)
 631 {
 632         bool need_butler = false;
 633         int retval;
 634
 635         assert (route);
 636
 637         DEBUG_TRACE (DEBUG::ProcessThreads, string_compose ("%1 runs route %2\n", pthread_self(), route->name()));
 638
 639         if (_process_silent) {
 640                 retval = route->silent_roll (_process_nframes, _process_start_frame, _process_end_frame, need_butler);
 641         } else if (_process_noroll) {
 642                 route->set_pending_declick (_process_declick);
 643                 retval = route->no_roll (_process_nframes, _process_start_frame, _process_end_frame, _process_non_rt_pending);
 644         } else {
 645                 route->set_pending_declick (_process_declick);
 646                 retval = route->roll (_process_nframes, _process_start_frame, _process_end_frame, _process_declick, need_butler);
 647         }
 648
 649         if (retval) {
 650                 _process_retval = retval;
 651         }
 652
 653         if (need_butler) {
 654                 _process_need_butler = true;
 655         }
 656 }
 657
 658 bool
 659 Graph::in_process_thread () const
 660 {
 661         list<pthread_t>::const_iterator i = _thread_list.begin ();
 662         while (i != _thread_list.end() && *i != pthread_self ()) {
 663                 ++i;
 664         }
 665
 666         return i != _thread_list.end ();
 667 }