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                 (*ri)->_init_refcount[chain] = 0;
 334                 (*ri)->_activation_set[chain].clear();
 335                 _nodes_rt[chain].push_back (*ri);
 336         }
 337
 338         // now add refs for the connections.
 339
 340         for (ni=_nodes_rt[chain].begin(); ni!=_nodes_rt[chain].end(); ni++) {
 341
 342                 /* We will set this to true if the node *ni is directly or
 343                    indirectly fed by anything (without feedback)
 344                 */
 345                 bool has_input  = false;
 346
 347                 /* We will set this to true if the node *ni directly feeds
 348                    anything (without feedback)
 349                 */
 350                 bool has_output = false;
 351
 352                 /* We will also set up *ni's _activation_set to contain any nodes
 353                    that it directly feeds.
 354                 */
 355
 356                 boost::shared_ptr<Route> rp = boost::dynamic_pointer_cast<Route>( *ni);
 357
 358                 for (RouteList::iterator ri=routelist->begin(); ri!=routelist->end(); ri++) {
 359                         if (rp->direct_feeds (*ri)) {
 360                                 if (is_feedback (routelist, rp.get(), *ri)) {
 361                                         continue;
 362                                 }
 363
 364                                 has_output = true;
 365                                 (*ni)->_activation_set[chain].insert (*ri);
 366                         }
 367                 }
 368
 369                 for (Route::FedBy::iterator fi=rp->fed_by().begin(); fi!=rp->fed_by().end(); fi++) {
 370                         if (boost::shared_ptr<Route> r = fi->r.lock()) {
 371                                 if (!is_feedback (routelist, r, rp.get())) {
 372                                         has_input = true;
 373                                 }
 374                         }
 375                 }
 376
 377                 /* Increment the refcount of any route that we directly feed */
 378                 for (node_set_t::iterator ai=(*ni)->_activation_set[chain].begin(); ai!=(*ni)->_activation_set[chain].end(); ai++) {
 379                         (*ai)->_init_refcount[chain] += 1;
 380                 }
 381
 382                 if (!has_input) {
 383                         _init_trigger_list[chain].push_back (*ni);
 384                 }
 385
 386                 if (!has_output) {
 387                         _init_finished_refcount[chain] += 1;
 388                 }
 389         }
 390
 391         _pending_chain = chain;
 392         dump(chain);
 393 }
 394
 395 /** Called by both the main thread and all helpers.
 396  *  @return true to quit, false to carry on.
 397  */
 398 bool
 399 Graph::run_one()
 400 {
 401         GraphNode* to_run;
 402
 403         pthread_mutex_lock (&_trigger_mutex);
 404         if (_trigger_queue.size()) {
 405                 to_run = _trigger_queue.back();
 406                 _trigger_queue.pop_back();
 407         } else {
 408                 to_run = 0;
 409         }
 410
 411         /* the number of threads that are asleep */
 412         int et = _execution_tokens;
 413         /* the number of nodes that need to be run */
 414         int ts = _trigger_queue.size();
 415
 416         /* hence how many threads to wake up */
 417         int wakeup = min (et, ts);
 418         /* update the number of threads that will still be sleeping */
 419         _execution_tokens -= wakeup;
 420
 421         DEBUG_TRACE(DEBUG::ProcessThreads, string_compose ("%1 signals %2\n", pthread_self(), wakeup));
 422
 423         for (int i = 0; i < wakeup; i++) {
 424                 _execution_sem.signal ();
 425         }
 426
 427         while (to_run == 0) {
 428                 _execution_tokens += 1;
 429                 pthread_mutex_unlock (&_trigger_mutex);
 430                 DEBUG_TRACE (DEBUG::ProcessThreads, string_compose ("%1 goes to sleep\n", pthread_self()));
 431                 _execution_sem.wait ();
 432                 if (_quit_threads) {
 433                         return true;
 434                 }
 435                 DEBUG_TRACE (DEBUG::ProcessThreads, string_compose ("%1 is awake\n", pthread_self()));
 436                 pthread_mutex_lock (&_trigger_mutex);
 437                 if (_trigger_queue.size()) {
 438                         to_run = _trigger_queue.back();
 439                         _trigger_queue.pop_back();
 440                 }
 441         }
 442         pthread_mutex_unlock (&_trigger_mutex);
 443
 444         to_run->process();
 445         to_run->finish (_current_chain);
 446
 447         DEBUG_TRACE(DEBUG::ProcessThreads, string_compose ("%1 has finished run_one()\n", pthread_self()));
 448
 449         return false;
 450 }
 451
 452 static void get_rt()
 453 {
 454         if (!jack_is_realtime (AudioEngine::instance()->jack())) {
 455                 return;
 456         }
 457
 458         int priority = jack_client_real_time_priority (AudioEngine::instance()->jack());
 459
 460         if (priority) {
 461                 struct sched_param rtparam;
 462
 463                 memset (&rtparam, 0, sizeof (rtparam));
 464                 rtparam.sched_priority = priority;
 465
 466                 pthread_setschedparam (pthread_self(), SCHED_FIFO, &rtparam);
 467         }
 468 }
 469
 470 void
 471 Graph::helper_thread()
 472 {
 473         suspend_rt_malloc_checks ();
 474         ProcessThread* pt = new ProcessThread ();
 475         resume_rt_malloc_checks ();
 476
 477         pt->get_buffers();
 478         get_rt();
 479
 480         while(1) {
 481                 if (run_one()) {
 482                         break;
 483                 }
 484         }
 485
 486         pt->drop_buffers();
 487 }
 488
 489 /** Here's the main graph thread */
 490 void
 491 Graph::main_thread()
 492 {
 493         suspend_rt_malloc_checks ();
 494         ProcessThread* pt = new ProcessThread ();
 495         resume_rt_malloc_checks ();
 496
 497         pt->get_buffers();
 498         get_rt();
 499
 500   again:
 501         _callback_start_sem.wait ();
 502
 503         DEBUG_TRACE(DEBUG::ProcessThreads, "main thread is awake\n");
 504
 505         if (_quit_threads) {
 506                 return;
 507         }
 508
 509         prep ();
 510
 511         if (_graph_empty && !_quit_threads) {
 512                 _callback_done_sem.signal ();
 513                 DEBUG_TRACE(DEBUG::ProcessThreads, "main thread sees graph done, goes back to sleep\n");
 514                 goto again;
 515         }
 516
 517         /* This loop will run forever */
 518         while (1) {
 519                 DEBUG_TRACE(DEBUG::ProcessThreads, "main thread runs one graph node\n");
 520                 if (run_one()) {
 521                         break;
 522                 }
 523         }
 524
 525         pt->drop_buffers();
 526 }
 527
 528 void
 529 Graph::dump (int chain)
 530 {
 531 #ifndef NDEBUG
 532         node_list_t::iterator ni;
 533         node_set_t::iterator ai;
 534
 535         chain = _pending_chain;
 536
 537         DEBUG_TRACE (DEBUG::Graph, "--------------------------------------------Graph dump:\n");
 538         for (ni=_nodes_rt[chain].begin(); ni!=_nodes_rt[chain].end(); ni++) {
 539                 boost::shared_ptr<Route> rp = boost::dynamic_pointer_cast<Route>( *ni);
 540                 DEBUG_TRACE (DEBUG::Graph, string_compose ("GraphNode: %1  refcount: %2\n", rp->name().c_str(), (*ni)->_init_refcount[chain]));
 541                 for (ai=(*ni)->_activation_set[chain].begin(); ai!=(*ni)->_activation_set[chain].end(); ai++) {
 542                         DEBUG_TRACE (DEBUG::Graph, string_compose ("  triggers: %1\n", boost::dynamic_pointer_cast<Route>(*ai)->name().c_str()));
 543                 }
 544         }
 545
 546         DEBUG_TRACE (DEBUG::Graph, "------------- trigger list:\n");
 547         for (ni=_init_trigger_list[chain].begin(); ni!=_init_trigger_list[chain].end(); ni++) {
 548                 DEBUG_TRACE (DEBUG::Graph, string_compose ("GraphNode: %1  refcount: %2\n", boost::dynamic_pointer_cast<Route>(*ni)->name().c_str(), (*ni)->_init_refcount[chain]));
 549         }
 550
 551         DEBUG_TRACE (DEBUG::Graph, string_compose ("final activation refcount: %1\n", _init_finished_refcount[chain]));
 552 #endif
 553 }
 554
 555 int
 556 Graph::silent_process_routes (pframes_t nframes, framepos_t start_frame, framepos_t end_frame, bool& need_butler)
 557 {
 558         _process_nframes = nframes;
 559         _process_start_frame = start_frame;
 560         _process_end_frame = end_frame;
 561
 562         _process_silent = true;
 563         _process_noroll = false;
 564         _process_retval = 0;
 565         _process_need_butler = false;
 566
 567         if (!_graph_empty) {
 568                 DEBUG_TRACE(DEBUG::ProcessThreads, "wake graph for silent process\n");
 569                 _callback_start_sem.signal ();
 570                 _callback_done_sem.wait ();
 571         }
 572
 573         need_butler = _process_need_butler;
 574
 575         return _process_retval;
 576 }
 577
 578 int
 579 Graph::process_routes (pframes_t nframes, framepos_t start_frame, framepos_t end_frame, int declick, bool& need_butler)
 580 {
 581         DEBUG_TRACE (DEBUG::ProcessThreads, string_compose ("graph execution from %1 to %2 = %3\n", start_frame, end_frame, nframes));
 582
 583         _process_nframes = nframes;
 584         _process_start_frame = start_frame;
 585         _process_end_frame = end_frame;
 586         _process_declick = declick;
 587
 588         _process_silent = false;
 589         _process_noroll = false;
 590         _process_retval = 0;
 591         _process_need_butler = false;
 592
 593         DEBUG_TRACE(DEBUG::ProcessThreads, "wake graph for non-silent process\n");
 594         _callback_start_sem.signal ();
 595         _callback_done_sem.wait ();
 596
 597         DEBUG_TRACE (DEBUG::ProcessThreads, "graph execution complete\n");
 598
 599         need_butler = _process_need_butler;
 600
 601         return _process_retval;
 602 }
 603
 604 int
 605 Graph::routes_no_roll (pframes_t nframes, framepos_t start_frame, framepos_t end_frame,
 606                        bool non_rt_pending, int declick)
 607 {
 608         DEBUG_TRACE (DEBUG::ProcessThreads, string_compose ("no-roll graph execution from %1 to %2 = %3\n", start_frame, end_frame, nframes));
 609
 610         _process_nframes = nframes;
 611         _process_start_frame = start_frame;
 612         _process_end_frame = end_frame;
 613         _process_declick = declick;
 614         _process_non_rt_pending = non_rt_pending;
 615
 616         _process_silent = false;
 617         _process_noroll = true;
 618         _process_retval = 0;
 619         _process_need_butler = false;
 620
 621         DEBUG_TRACE(DEBUG::ProcessThreads, "wake graph for no-roll process\n");
 622         _callback_start_sem.signal ();
 623         _callback_done_sem.wait ();
 624
 625         return _process_retval;
 626 }
 627 void
 628 Graph::process_one_route (Route* route)
 629 {
 630         bool need_butler = false;
 631         int retval;
 632
 633         assert (route);
 634
 635         DEBUG_TRACE (DEBUG::ProcessThreads, string_compose ("%1 runs route %2\n", pthread_self(), route->name()));
 636
 637         if (_process_silent) {
 638                 retval = route->silent_roll (_process_nframes, _process_start_frame, _process_end_frame, need_butler);
 639         } else if (_process_noroll) {
 640                 route->set_pending_declick (_process_declick);
 641                 retval = route->no_roll (_process_nframes, _process_start_frame, _process_end_frame, _process_non_rt_pending);
 642         } else {
 643                 route->set_pending_declick (_process_declick);
 644                 retval = route->roll (_process_nframes, _process_start_frame, _process_end_frame, _process_declick, need_butler);
 645         }
 646
 647         if (retval) {
 648                 _process_retval = retval;
 649         }
 650
 651         if (need_butler) {
 652                 _process_need_butler = true;
 653         }
 654 }
 655
 656 bool
 657 Graph::in_process_thread () const
 658 {
 659         list<pthread_t>::const_iterator i = _thread_list.begin ();
 660         while (i != _thread_list.end() && *i != pthread_self ()) {
 661                 ++i;
 662         }
 663
 664         return i != _thread_list.end ();
 665 }