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 #include <poll.h>
  24 #include "pbd/error.h"
  25 #include "pbd/pthread_utils.h"
  26 #include "ardour/butler.h"
  27 #include "ardour/io.h"
  28 #include "ardour/midi_diskstream.h"
  29 #include "ardour/session.h"
  30 #include "ardour/track.h"
  31 #include "ardour/auditioner.h"
  32
  33 #include "i18n.h"
  34
  35 using namespace PBD;
  36
  37 namespace ARDOUR {
  38
  39 Butler::Butler(Session& s)
  40         : SessionHandleRef (s)
  41         , thread(0)
  42         , audio_dstream_capture_buffer_size(0)
  43         , audio_dstream_playback_buffer_size(0)
  44         , midi_dstream_buffer_size(0)
  45         , pool_trash(16)
  46 {
  47         g_atomic_int_set(&should_do_transport_work, 0);
  48         SessionEvent::pool->set_trash (&pool_trash);
  49
  50         Config->ParameterChanged.connect_same_thread (*this, boost::bind (&Butler::config_changed, this, _1));
  51 }
  52
  53 Butler::~Butler()
  54 {
  55         terminate_thread ();
  56 }
  57
  58 void
  59 Butler::config_changed (std::string p)
  60 {
  61         if (p == "playback-buffer-seconds") {
  62                 /* size is in Samples, not bytes */
  63                 audio_dstream_playback_buffer_size = (uint32_t) floor (Config->get_audio_playback_buffer_seconds() * _session.frame_rate());
  64                 _session.adjust_playback_buffering ();
  65         } else if (p == "capture-buffer-seconds") {
  66                 audio_dstream_capture_buffer_size = (uint32_t) floor (Config->get_audio_capture_buffer_seconds() * _session.frame_rate());
  67                 _session.adjust_capture_buffering ();
  68         }
  69 }
  70
  71 int
  72 Butler::start_thread()
  73 {
  74         const float rate = (float)_session.frame_rate();
  75
  76         /* size is in Samples, not bytes */
  77         audio_dstream_capture_buffer_size = (uint32_t) floor (Config->get_audio_capture_buffer_seconds() * rate);
  78         audio_dstream_playback_buffer_size = (uint32_t) floor (Config->get_audio_playback_buffer_seconds() * rate);
  79
  80         /* size is in bytes
  81          * XXX: Jack needs to tell us the MIDI buffer size
  82          * (i.e. how many MIDI bytes we might see in a cycle)
  83          */
  84         midi_dstream_buffer_size = (uint32_t) floor (Config->get_midi_track_buffer_seconds() * rate);
  85
  86         MidiDiskstream::set_readahead_frames ((framecnt_t) (Config->get_midi_readahead() * rate));
  87
  88         should_run = false;
  89
  90         if (pipe (request_pipe)) {
  91                 error << string_compose(_("Cannot create transport request signal pipe (%1)"),
  92                                 strerror (errno)) << endmsg;
  93                 return -1;
  94         }
  95
  96         if (fcntl (request_pipe[0], F_SETFL, O_NONBLOCK)) {
  97                 error << string_compose(_("UI: cannot set O_NONBLOCK on butler request pipe (%1)"),
  98                                 strerror (errno)) << endmsg;
  99                 return -1;
 100         }
 101
 102         if (fcntl (request_pipe[1], F_SETFL, O_NONBLOCK)) {
 103                 error << string_compose(_("UI: cannot set O_NONBLOCK on butler request pipe (%1)"),
 104                                 strerror (errno)) << endmsg;
 105                 return -1;
 106         }
 107
 108         if (pthread_create_and_store ("disk butler", &thread, _thread_work, this)) {
 109                 error << _("Session: could not create butler thread") << endmsg;
 110                 return -1;
 111         }
 112
 113         //pthread_detach (thread);
 114
 115         return 0;
 116 }
 117
 118 void
 119 Butler::terminate_thread ()
 120 {
 121         if (thread) {
 122                 void* status;
 123                 const char c = Request::Quit;
 124                 (void) ::write (request_pipe[1], &c, 1);
 125                 pthread_join (thread, &status);
 126         }
 127 }
 128
 129 void *
 130 Butler::_thread_work (void* arg)
 131 {
 132         SessionEvent::create_per_thread_pool ("butler events", 4096);
 133         pthread_set_name (X_("butler"));
 134         return ((Butler *) arg)->thread_work ();
 135 }
 136
 137 void *
 138 Butler::thread_work ()
 139 {
 140         uint32_t err = 0;
 141
 142         struct pollfd pfd[1];
 143         bool disk_work_outstanding = false;
 144         RouteList::iterator i;
 145
 146         while (true) {
 147                 pfd[0].fd = request_pipe[0];
 148                 pfd[0].events = POLLIN|POLLERR|POLLHUP;
 149
 150                 if (poll (pfd, 1, (disk_work_outstanding ? 0 : -1)) < 0) {
 151
 152                         if (errno == EINTR) {
 153                                 continue;
 154                         }
 155
 156                         error << string_compose (_("poll on butler request pipe failed (%1)"),
 157                                           strerror (errno))
 158                               << endmsg;
 159                         break;
 160                 }
 161
 162                 if (pfd[0].revents & ~POLLIN) {
 163                         error << string_compose (_("Error on butler thread request pipe: fd=%1 err=%2"), pfd[0].fd, pfd[0].revents) << endmsg;
 164                         break;
 165                 }
 166
 167                 if (pfd[0].revents & POLLIN) {
 168
 169                         char req;
 170
 171                         /* empty the pipe of all current requests */
 172
 173                         while (1) {
 174                                 size_t nread = ::read (request_pipe[0], &req, sizeof (req));
 175                                 if (nread == 1) {
 176
 177                                         switch ((Request::Type) req) {
 178
 179                                         case Request::Run:
 180                                                 should_run = true;
 181                                                 break;
 182
 183                                         case Request::Pause:
 184                                                 should_run = false;
 185                                                 break;
 186
 187                                         case Request::Quit:
 188                                                 pthread_exit_pbd (0);
 189                                                 /*NOTREACHED*/
 190                                                 break;
 191
 192                                         default:
 193                                                 break;
 194                                         }
 195
 196                                 } else if (nread == 0) {
 197                                         break;
 198                                 } else if (errno == EAGAIN) {
 199                                         break;
 200                                 } else {
 201                                         fatal << _("Error reading from butler request pipe") << endmsg;
 202                                         /*NOTREACHED*/
 203                                 }
 204                         }
 205                 }
 206
 207
 208 restart:
 209                 disk_work_outstanding = false;
 210
 211                 if (transport_work_requested()) {
 212                         _session.butler_transport_work ();
 213                 }
 214
 215                 boost::shared_ptr<RouteList> rl = _session.get_routes();
 216
 217                 RouteList rl_with_auditioner = *rl;
 218                 rl_with_auditioner.push_back (_session.the_auditioner());
 219
 220 //              for (i = dsl->begin(); i != dsl->end(); ++i) {
 221 //                      cerr << "BEFORE " << (*i)->name() << ": pb = " << (*i)->playback_buffer_load() << " cp = " << (*i)->capture_buffer_load() << endl;
 222 //              }
 223
 224                 for (i = rl_with_auditioner.begin(); !transport_work_requested() && should_run && i != rl_with_auditioner.end(); ++i) {
 225
 226                         boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 227
 228                         if (!tr) {
 229                                 continue;
 230                         }
 231
 232                         boost::shared_ptr<IO> io = tr->input ();
 233
 234                         if (io && !io->active()) {
 235                                 /* don't read inactive tracks */
 236                                 continue;
 237                         }
 238
 239                         switch (tr->do_refill ()) {
 240                         case 0:
 241                                 break;
 242
 243                         case 1:
 244                                 disk_work_outstanding = true;
 245                                 break;
 246
 247                         default:
 248                                 error << string_compose(_("Butler read ahead failure on dstream %1"), (*i)->name()) << endmsg;
 249                                 break;
 250                         }
 251
 252                 }
 253
 254                 if (i != rl_with_auditioner.begin() && i != rl_with_auditioner.end()) {
 255                         /* we didn't get to all the streams */
 256                         disk_work_outstanding = true;
 257                 }
 258
 259                 if (!err && transport_work_requested()) {
 260                         goto restart;
 261                 }
 262
 263                 for (i = rl->begin(); !transport_work_requested() && should_run && i != rl->end(); ++i) {
 264                         // cerr << "write behind for " << (*i)->name () << endl;
 265
 266                         boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 267
 268                         if (!tr) {
 269                                 continue;
 270                         }
 271
 272                         /* note that we still try to flush diskstreams attached to inactive routes
 273                          */
 274
 275                         switch (tr->do_flush (ButlerContext)) {
 276                         case 0:
 277                                 break;
 278
 279                         case 1:
 280                                 disk_work_outstanding = true;
 281                                 break;
 282
 283                         default:
 284                                 err++;
 285                                 error << string_compose(_("Butler write-behind failure on dstream %1"), (*i)->name()) << endmsg;
 286                                 /* don't break - try to flush all streams in case they
 287                                    are split across disks.
 288                                 */
 289                         }
 290                 }
 291
 292                 if (err && _session.actively_recording()) {
 293                         /* stop the transport and try to catch as much possible
 294                            captured state as we can.
 295                         */
 296                         _session.request_stop ();
 297                 }
 298
 299                 if (i != rl->begin() && i != rl->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                 if (!disk_work_outstanding) {
 309                         _session.refresh_disk_space ();
 310                 }
 311
 312
 313                 {
 314                         Glib::Threads::Mutex::Lock lm (request_lock);
 315
 316                         if (should_run && (disk_work_outstanding || transport_work_requested())) {
 317 //                              for (DiskstreamList::iterator i = dsl->begin(); i != dsl->end(); ++i) {
 318 //                                      cerr << "AFTER " << (*i)->name() << ": pb = " << (*i)->playback_buffer_load() << " cp = " << (*i)->capture_buffer_load() << endl;
 319 //                              }
 320
 321                                 goto restart;
 322                         }
 323
 324                         paused.signal();
 325                 }
 326
 327                 empty_pool_trash ();
 328         }
 329
 330         pthread_exit_pbd (0);
 331         /*NOTREACHED*/
 332         return (0);
 333 }
 334
 335 void
 336 Butler::schedule_transport_work ()
 337 {
 338         g_atomic_int_inc (&should_do_transport_work);
 339         summon ();
 340 }
 341
 342 void
 343 Butler::summon ()
 344 {
 345         char c = Request::Run;
 346         (void) ::write (request_pipe[1], &c, 1);
 347 }
 348
 349 void
 350 Butler::stop ()
 351 {
 352         Glib::Threads::Mutex::Lock lm (request_lock);
 353         char c = Request::Pause;
 354         (void) ::write (request_pipe[1], &c, 1);
 355         paused.wait(request_lock);
 356 }
 357
 358 void
 359 Butler::wait_until_finished ()
 360 {
 361         Glib::Threads::Mutex::Lock lm (request_lock);
 362         char c = Request::Pause;
 363         (void) ::write (request_pipe[1], &c, 1);
 364         paused.wait(request_lock);
 365 }
 366
 367 bool
 368 Butler::transport_work_requested () const
 369 {
 370         return g_atomic_int_get(&should_do_transport_work);
 371 }
 372
 373 void
 374 Butler::empty_pool_trash ()
 375 {
 376         /* look in the trash, deleting empty pools until we come to one that is not empty */
 377
 378         RingBuffer<CrossThreadPool*>::rw_vector vec;
 379         pool_trash.get_read_vector (&vec);
 380
 381         guint deleted = 0;
 382
 383         for (int i = 0; i < 2; ++i) {
 384                 for (guint j = 0; j < vec.len[i]; ++j) {
 385                         if (vec.buf[i][j]->empty()) {
 386                                 delete vec.buf[i][j];
 387                                 ++deleted;
 388                         } else {
 389                                 /* found a non-empty pool, so stop deleting */
 390                                 if (deleted) {
 391                                         pool_trash.increment_read_idx (deleted);
 392                                 }
 393                                 return;
 394                         }
 395                 }
 396         }
 397
 398         if (deleted) {
 399                 pool_trash.increment_read_idx (deleted);
 400         }
 401 }
 402
 403 void
 404 Butler::drop_references ()
 405 {
 406         SessionEvent::pool->set_trash (0);
 407 }
 408
 409
 410 } // namespace ARDOUR
 411