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