libs/ardour/butler.cc

   1 /*
   2     Copyright (C) 1999-2009 Paul Davis
   3
   4     This program is free software; you can redistribute it and/or modify
   5     it under the terms of the GNU General Public License as published by
   6     the Free Software Foundation; either version 2 of the License, or
   7     (at your option) any later version.
   8
   9     This program is distributed in the hope that it will be useful,
  10     but WITHOUT ANY WARRANTY; without even the implied warranty of
  11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12     GNU General Public License for more details.
  13
  14     You should have received a copy of the GNU General Public License
  15     along with this program; if not, write to the Free Software
  16     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  17
  18 */
  19
  20 #include <errno.h>
  21 #include <fcntl.h>
  22 #include <unistd.h>
  23
  24 #ifndef PLATFORM_WINDOWS
  25 #include <poll.h>
  26 #endif
  27
  28 #include "pbd/error.h"
  29 #include "pbd/pthread_utils.h"
  30 #include "ardour/butler.h"
  31 #include "ardour/io.h"
  32 #include "ardour/midi_diskstream.h"
  33 #include "ardour/session.h"
  34 #include "ardour/track.h"
  35 #include "ardour/auditioner.h"
  36
  37 #include "i18n.h"
  38
  39 using namespace PBD;
  40
  41 namespace ARDOUR {
  42
  43 Butler::Butler(Session& s)
  44         : SessionHandleRef (s)
  45         , thread()
  46         , have_thread (false)
  47         , audio_dstream_capture_buffer_size(0)
  48         , audio_dstream_playback_buffer_size(0)
  49         , midi_dstream_buffer_size(0)
  50         , pool_trash(16)
  51 {
  52         g_atomic_int_set(&should_do_transport_work, 0);
  53         SessionEvent::pool->set_trash (&pool_trash);
  54
  55         Config->ParameterChanged.connect_same_thread (*this, boost::bind (&Butler::config_changed, this, _1));
  56 }
  57
  58 Butler::~Butler()
  59 {
  60         terminate_thread ();
  61 }
  62
  63 void
  64 Butler::config_changed (std::string p)
  65 {
  66         if (p == "playback-buffer-seconds") {
  67                 /* size is in Samples, not bytes */
  68                 audio_dstream_playback_buffer_size = (uint32_t) floor (Config->get_audio_playback_buffer_seconds() * _session.frame_rate());
  69                 _session.adjust_playback_buffering ();
  70         } else if (p == "capture-buffer-seconds") {
  71                 audio_dstream_capture_buffer_size = (uint32_t) floor (Config->get_audio_capture_buffer_seconds() * _session.frame_rate());
  72                 _session.adjust_capture_buffering ();
  73         }
  74 }
  75
  76 #ifndef PLATFORM_WINDOWS
  77 int
  78 Butler::setup_request_pipe ()
  79 {
  80         if (pipe (request_pipe)) {
  81                 error << string_compose(_("Cannot create transport request signal pipe (%1)"),
  82                                 strerror (errno)) << endmsg;
  83                 return -1;
  84         }
  85
  86         if (fcntl (request_pipe[0], F_SETFL, O_NONBLOCK)) {
  87                 error << string_compose(_("UI: cannot set O_NONBLOCK on butler request pipe (%1)"),
  88                                 strerror (errno)) << endmsg;
  89                 return -1;
  90         }
  91
  92         if (fcntl (request_pipe[1], F_SETFL, O_NONBLOCK)) {
  93                 error << string_compose(_("UI: cannot set O_NONBLOCK on butler request pipe (%1)"),
  94                                 strerror (errno)) << endmsg;
  95                 return -1;
  96         }
  97         return 0;
  98 }
  99 #endif
 100
 101 int
 102 Butler::start_thread()
 103 {
 104         const float rate = (float)_session.frame_rate();
 105
 106         /* size is in Samples, not bytes */
 107         audio_dstream_capture_buffer_size = (uint32_t) floor (Config->get_audio_capture_buffer_seconds() * rate);
 108         audio_dstream_playback_buffer_size = (uint32_t) floor (Config->get_audio_playback_buffer_seconds() * rate);
 109
 110         /* size is in bytes
 111          * XXX: Jack needs to tell us the MIDI buffer size
 112          * (i.e. how many MIDI bytes we might see in a cycle)
 113          */
 114         midi_dstream_buffer_size = (uint32_t) floor (Config->get_midi_track_buffer_seconds() * rate);
 115
 116         MidiDiskstream::set_readahead_frames ((framecnt_t) (Config->get_midi_readahead() * rate));
 117
 118         should_run = false;
 119
 120 #ifndef PLATFORM_WINDOWS
 121         if (setup_request_pipe() != 0) return -1;
 122 #endif
 123
 124         if (pthread_create_and_store ("disk butler", &thread, _thread_work, this)) {
 125                 error << _("Session: could not create butler thread") << endmsg;
 126                 return -1;
 127         }
 128
 129         //pthread_detach (thread);
 130         have_thread = true;
 131         return 0;
 132 }
 133
 134 void
 135 Butler::terminate_thread ()
 136 {
 137         if (have_thread) {
 138                 void* status;
 139                 queue_request (Request::Quit);
 140                 pthread_join (thread, &status);
 141         }
 142 }
 143
 144 void *
 145 Butler::_thread_work (void* arg)
 146 {
 147         SessionEvent::create_per_thread_pool ("butler events", 4096);
 148         pthread_set_name (X_("butler"));
 149         return ((Butler *) arg)->thread_work ();
 150 }
 151
 152 bool
 153 Butler::wait_for_requests ()
 154 {
 155 #ifndef PLATFORM_WINDOWS
 156         struct pollfd pfd[1];
 157
 158         pfd[0].fd = request_pipe[0];
 159         pfd[0].events = POLLIN|POLLERR|POLLHUP;
 160
 161         while(true) {
 162                 if (poll (pfd, 1, -1) < 0) {
 163
 164                         if (errno == EINTR) {
 165                                 continue;
 166                         }
 167
 168                         error << string_compose (_("poll on butler request pipe failed (%1)"),
 169                                         strerror (errno))
 170                                 << endmsg;
 171                         break;
 172                 }
 173
 174                 if (pfd[0].revents & ~POLLIN) {
 175                         error << string_compose (_("Error on butler thread request pipe: fd=%1 err=%2"), pfd[0].fd, pfd[0].revents) << endmsg;
 176                         break;
 177                 }
 178
 179                 if (pfd[0].revents & POLLIN) {
 180                         return true;
 181                 }
 182         }
 183         return false;
 184 #else
 185         m_request_sem.wait ();
 186         return true;
 187 #endif
 188 }
 189
 190 bool
 191 Butler::dequeue_request (Request::Type& r)
 192 {
 193 #ifndef PLATFORM_WINDOWS
 194         char req;
 195         size_t nread = ::read (request_pipe[0], &req, sizeof (req));
 196         if (nread == 1) {
 197                 r = (Request::Type) req;
 198                 return true;
 199         } else if (nread == 0) {
 200                 return false;
 201         } else if (errno == EAGAIN) {
 202                 return false;
 203         } else {
 204                 fatal << _("Error reading from butler request pipe") << endmsg;
 205                 /*NOTREACHED*/
 206         }
 207 #else
 208         r = (Request::Type) m_request_state.get();
 209 #endif
 210         return false;
 211 }
 212
 213         void *
 214 Butler::thread_work ()
 215 {
 216         uint32_t err = 0;
 217
 218         bool disk_work_outstanding = false;
 219         RouteList::iterator i;
 220
 221         while (true) {
 222                 if(!disk_work_outstanding) {
 223                         if (wait_for_requests ()) {
 224                                 Request::Type req;
 225
 226                                 /* empty the pipe of all current requests */
 227 #ifdef PLATFORM_WINDOWS
 228                                 dequeue_request (req);
 229                                 {
 230 #else
 231                                 while(dequeue_request(req)) {
 232 #endif
 233                                         switch (req) {
 234
 235                                         case Request::Run:
 236                                                 should_run = true;
 237                                                 break;
 238
 239                                         case Request::Pause:
 240                                                 should_run = false;
 241                                                 break;
 242
 243                                         case Request::Quit:
 244                                                 return 0;
 245                                                 /*NOTREACHED*/
 246                                                 break;
 247
 248                                         default:
 249                                                 break;
 250                                         }
 251                                 }
 252                         }
 253                 }
 254
 255
 256 restart:
 257                 disk_work_outstanding = false;
 258
 259                 if (transport_work_requested()) {
 260                         _session.butler_transport_work ();
 261                 }
 262
 263                 frameoffset_t audition_seek;
 264                 if (should_run && _session.is_auditioning()
 265                                 && (audition_seek = _session.the_auditioner()->seek_frame()) >= 0) {
 266                         boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (_session.the_auditioner());
 267                         tr->seek(audition_seek);
 268                         _session.the_auditioner()->seek_response(audition_seek);
 269                 }
 270
 271                 boost::shared_ptr<RouteList> rl = _session.get_routes();
 272
 273                 RouteList rl_with_auditioner = *rl;
 274                 rl_with_auditioner.push_back (_session.the_auditioner());
 275
 276 //              for (i = dsl->begin(); i != dsl->end(); ++i) {
 277 //                      cerr << "BEFORE " << (*i)->name() << ": pb = " << (*i)->playback_buffer_load() << " cp = " << (*i)->capture_buffer_load() << endl;
 278 //              }
 279
 280                 for (i = rl_with_auditioner.begin(); !transport_work_requested() && should_run && i != rl_with_auditioner.end(); ++i) {
 281
 282                         boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 283
 284                         if (!tr) {
 285                                 continue;
 286                         }
 287
 288                         boost::shared_ptr<IO> io = tr->input ();
 289
 290                         if (io && !io->active()) {
 291                                 /* don't read inactive tracks */
 292                                 continue;
 293                         }
 294
 295                         switch (tr->do_refill ()) {
 296                         case 0:
 297                                 break;
 298
 299                         case 1:
 300                                 disk_work_outstanding = true;
 301                                 break;
 302
 303                         default:
 304                                 error << string_compose(_("Butler read ahead failure on dstream %1"), (*i)->name()) << endmsg;
 305                                 break;
 306                         }
 307
 308                 }
 309
 310                 if (i != rl_with_auditioner.begin() && i != rl_with_auditioner.end()) {
 311                         /* we didn't get to all the streams */
 312                         disk_work_outstanding = true;
 313                 }
 314
 315                 if (!err && transport_work_requested()) {
 316                         goto restart;
 317                 }
 318
 319                 for (i = rl->begin(); !transport_work_requested() && should_run && i != rl->end(); ++i) {
 320                         // cerr << "write behind for " << (*i)->name () << endl;
 321
 322                         boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 323
 324                         if (!tr) {
 325                                 continue;
 326                         }
 327
 328                         /* note that we still try to flush diskstreams attached to inactive routes
 329                          */
 330
 331                         switch (tr->do_flush (ButlerContext)) {
 332                         case 0:
 333                                 break;
 334
 335                         case 1:
 336                                 disk_work_outstanding = true;
 337                                 break;
 338
 339                         default:
 340                                 err++;
 341                                 error << string_compose(_("Butler write-behind failure on dstream %1"), (*i)->name()) << endmsg;
 342                                 /* don't break - try to flush all streams in case they
 343                                    are split across disks.
 344                                 */
 345                         }
 346                 }
 347
 348                 if (err && _session.actively_recording()) {
 349                         /* stop the transport and try to catch as much possible
 350                            captured state as we can.
 351                         */
 352                         _session.request_stop ();
 353                 }
 354
 355                 if (i != rl->begin() && i != rl->end()) {
 356                         /* we didn't get to all the streams */
 357                         disk_work_outstanding = true;
 358                 }
 359
 360                 if (!err && transport_work_requested()) {
 361                         goto restart;
 362                 }
 363
 364                 if (!disk_work_outstanding) {
 365                         _session.refresh_disk_space ();
 366                 }
 367
 368
 369                 {
 370                         Glib::Threads::Mutex::Lock lm (request_lock);
 371
 372                         if (should_run && (disk_work_outstanding || transport_work_requested())) {
 373 //                              for (DiskstreamList::iterator i = dsl->begin(); i != dsl->end(); ++i) {
 374 //                                      cerr << "AFTER " << (*i)->name() << ": pb = " << (*i)->playback_buffer_load() << " cp = " << (*i)->capture_buffer_load() << endl;
 375 //                              }
 376
 377                                 goto restart;
 378                         }
 379
 380                         paused.signal();
 381                 }
 382
 383                 empty_pool_trash ();
 384         }
 385
 386         return (0);
 387 }
 388
 389 void
 390 Butler::schedule_transport_work ()
 391 {
 392         g_atomic_int_inc (&should_do_transport_work);
 393         summon ();
 394 }
 395
 396 void
 397 Butler::queue_request (Request::Type r)
 398 {
 399 #ifndef PLATFORM_WINDOWS
 400         char c = r;
 401         (void) ::write (request_pipe[1], &c, 1);
 402 #else
 403         m_request_state.set (r);
 404         m_request_sem.post ();
 405 #endif
 406 }
 407
 408 void
 409 Butler::summon ()
 410 {
 411         queue_request (Request::Run);
 412 }
 413
 414 void
 415 Butler::stop ()
 416 {
 417         Glib::Threads::Mutex::Lock lm (request_lock);
 418         queue_request (Request::Pause);
 419         paused.wait(request_lock);
 420 }
 421
 422 void
 423 Butler::wait_until_finished ()
 424 {
 425         Glib::Threads::Mutex::Lock lm (request_lock);
 426         queue_request (Request::Pause);
 427         paused.wait(request_lock);
 428 }
 429
 430 bool
 431 Butler::transport_work_requested () const
 432 {
 433         return g_atomic_int_get(&should_do_transport_work);
 434 }
 435
 436 void
 437 Butler::empty_pool_trash ()
 438 {
 439         /* look in the trash, deleting empty pools until we come to one that is not empty */
 440
 441         RingBuffer<CrossThreadPool*>::rw_vector vec;
 442         pool_trash.get_read_vector (&vec);
 443
 444         guint deleted = 0;
 445
 446         for (int i = 0; i < 2; ++i) {
 447                 for (guint j = 0; j < vec.len[i]; ++j) {
 448                         if (vec.buf[i][j]->empty()) {
 449                                 delete vec.buf[i][j];
 450                                 ++deleted;
 451                         } else {
 452                                 /* found a non-empty pool, so stop deleting */
 453                                 if (deleted) {
 454                                         pool_trash.increment_read_idx (deleted);
 455                                 }
 456                                 return;
 457                         }
 458                 }
 459         }
 460
 461         if (deleted) {
 462                 pool_trash.increment_read_idx (deleted);
 463         }
 464 }
 465
 466 void
 467 Butler::drop_references ()
 468 {
 469         cerr << "Butler drops pool trash\n";
 470         SessionEvent::pool->set_trash (0);
 471 }
 472
 473
 474 } // namespace ARDOUR
 475