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         fcntl(request_pipe[0], F_SETFD, fcntl(request_pipe[0], F_GETFD) | FD_CLOEXEC);
 114         fcntl(request_pipe[1], F_SETFD, fcntl(request_pipe[1], F_GETFD) | FD_CLOEXEC);
 115
 116         //pthread_detach (thread);
 117
 118         return 0;
 119 }
 120
 121 void
 122 Butler::terminate_thread ()
 123 {
 124         if (thread) {
 125                 void* status;
 126                 const char c = Request::Quit;
 127                 (void) ::write (request_pipe[1], &c, 1);
 128                 pthread_join (thread, &status);
 129         }
 130 }
 131
 132 void *
 133 Butler::_thread_work (void* arg)
 134 {
 135         SessionEvent::create_per_thread_pool ("butler events", 4096);
 136         pthread_set_name (X_("butler"));
 137         return ((Butler *) arg)->thread_work ();
 138 }
 139
 140 void *
 141 Butler::thread_work ()
 142 {
 143         uint32_t err = 0;
 144
 145         struct pollfd pfd[1];
 146         bool disk_work_outstanding = false;
 147         RouteList::iterator i;
 148
 149         while (true) {
 150                 pfd[0].fd = request_pipe[0];
 151                 pfd[0].events = POLLIN|POLLERR|POLLHUP;
 152
 153                 if (poll (pfd, 1, (disk_work_outstanding ? 0 : -1)) < 0) {
 154
 155                         if (errno == EINTR) {
 156                                 continue;
 157                         }
 158
 159                         error << string_compose (_("poll on butler request pipe failed (%1)"),
 160                                           strerror (errno))
 161                               << endmsg;
 162                         break;
 163                 }
 164
 165                 if (pfd[0].revents & ~POLLIN) {
 166                         error << string_compose (_("Error on butler thread request pipe: fd=%1 err=%2"), pfd[0].fd, pfd[0].revents) << endmsg;
 167                         break;
 168                 }
 169
 170                 if (pfd[0].revents & POLLIN) {
 171
 172                         char req;
 173
 174                         /* empty the pipe of all current requests */
 175
 176                         while (1) {
 177                                 size_t nread = ::read (request_pipe[0], &req, sizeof (req));
 178                                 if (nread == 1) {
 179
 180                                         switch ((Request::Type) req) {
 181
 182                                         case Request::Run:
 183                                                 should_run = true;
 184                                                 break;
 185
 186                                         case Request::Pause:
 187                                                 should_run = false;
 188                                                 break;
 189
 190                                         case Request::Quit:
 191                                                 pthread_exit_pbd (0);
 192                                                 /*NOTREACHED*/
 193                                                 break;
 194
 195                                         default:
 196                                                 break;
 197                                         }
 198
 199                                 } else if (nread == 0) {
 200                                         break;
 201                                 } else if (errno == EAGAIN) {
 202                                         break;
 203                                 } else {
 204                                         fatal << _("Error reading from butler request pipe") << endmsg;
 205                                         /*NOTREACHED*/
 206                                 }
 207                         }
 208                 }
 209
 210
 211 restart:
 212                 disk_work_outstanding = false;
 213
 214                 if (transport_work_requested()) {
 215                         _session.butler_transport_work ();
 216                 }
 217
 218                 boost::shared_ptr<RouteList> rl = _session.get_routes();
 219
 220                 RouteList rl_with_auditioner = *rl;
 221                 rl_with_auditioner.push_back (_session.the_auditioner());
 222
 223 //              for (i = dsl->begin(); i != dsl->end(); ++i) {
 224 //                      cerr << "BEFORE " << (*i)->name() << ": pb = " << (*i)->playback_buffer_load() << " cp = " << (*i)->capture_buffer_load() << endl;
 225 //              }
 226
 227                 for (i = rl_with_auditioner.begin(); !transport_work_requested() && should_run && i != rl_with_auditioner.end(); ++i) {
 228
 229                         boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 230
 231                         if (!tr) {
 232                                 continue;
 233                         }
 234
 235                         boost::shared_ptr<IO> io = tr->input ();
 236
 237                         if (io && !io->active()) {
 238                                 /* don't read inactive tracks */
 239                                 continue;
 240                         }
 241
 242                         switch (tr->do_refill ()) {
 243                         case 0:
 244                                 break;
 245
 246                         case 1:
 247                                 disk_work_outstanding = true;
 248                                 break;
 249
 250                         default:
 251                                 error << string_compose(_("Butler read ahead failure on dstream %1"), (*i)->name()) << endmsg;
 252                                 break;
 253                         }
 254
 255                 }
 256
 257                 if (i != rl_with_auditioner.begin() && i != rl_with_auditioner.end()) {
 258                         /* we didn't get to all the streams */
 259                         disk_work_outstanding = true;
 260                 }
 261
 262                 if (!err && transport_work_requested()) {
 263                         goto restart;
 264                 }
 265
 266                 for (i = rl->begin(); !transport_work_requested() && should_run && i != rl->end(); ++i) {
 267                         // cerr << "write behind for " << (*i)->name () << endl;
 268
 269                         boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 270
 271                         if (!tr) {
 272                                 continue;
 273                         }
 274
 275                         /* note that we still try to flush diskstreams attached to inactive routes
 276                          */
 277
 278                         switch (tr->do_flush (ButlerContext)) {
 279                         case 0:
 280                                 break;
 281
 282                         case 1:
 283                                 disk_work_outstanding = true;
 284                                 break;
 285
 286                         default:
 287                                 err++;
 288                                 error << string_compose(_("Butler write-behind failure on dstream %1"), (*i)->name()) << endmsg;
 289                                 /* don't break - try to flush all streams in case they
 290                                    are split across disks.
 291                                 */
 292                         }
 293                 }
 294
 295                 if (err && _session.actively_recording()) {
 296                         /* stop the transport and try to catch as much possible
 297                            captured state as we can.
 298                         */
 299                         _session.request_stop ();
 300                 }
 301
 302                 if (i != rl->begin() && i != rl->end()) {
 303                         /* we didn't get to all the streams */
 304                         disk_work_outstanding = true;
 305                 }
 306
 307                 if (!err && transport_work_requested()) {
 308                         goto restart;
 309                 }
 310
 311                 if (!disk_work_outstanding) {
 312                         _session.refresh_disk_space ();
 313                 }
 314
 315
 316                 {
 317                         Glib::Threads::Mutex::Lock lm (request_lock);
 318
 319                         if (should_run && (disk_work_outstanding || transport_work_requested())) {
 320 //                              for (DiskstreamList::iterator i = dsl->begin(); i != dsl->end(); ++i) {
 321 //                                      cerr << "AFTER " << (*i)->name() << ": pb = " << (*i)->playback_buffer_load() << " cp = " << (*i)->capture_buffer_load() << endl;
 322 //                              }
 323
 324                                 goto restart;
 325                         }
 326
 327                         paused.signal();
 328                 }
 329
 330                 empty_pool_trash ();
 331         }
 332
 333         pthread_exit_pbd (0);
 334         /*NOTREACHED*/
 335         return (0);
 336 }
 337
 338 void
 339 Butler::schedule_transport_work ()
 340 {
 341         g_atomic_int_inc (&should_do_transport_work);
 342         summon ();
 343 }
 344
 345 void
 346 Butler::summon ()
 347 {
 348         char c = Request::Run;
 349         (void) ::write (request_pipe[1], &c, 1);
 350 }
 351
 352 void
 353 Butler::stop ()
 354 {
 355         Glib::Threads::Mutex::Lock lm (request_lock);
 356         char c = Request::Pause;
 357         (void) ::write (request_pipe[1], &c, 1);
 358         paused.wait(request_lock);
 359 }
 360
 361 void
 362 Butler::wait_until_finished ()
 363 {
 364         Glib::Threads::Mutex::Lock lm (request_lock);
 365         char c = Request::Pause;
 366         (void) ::write (request_pipe[1], &c, 1);
 367         paused.wait(request_lock);
 368 }
 369
 370 bool
 371 Butler::transport_work_requested () const
 372 {
 373         return g_atomic_int_get(&should_do_transport_work);
 374 }
 375
 376 void
 377 Butler::empty_pool_trash ()
 378 {
 379         /* look in the trash, deleting empty pools until we come to one that is not empty */
 380
 381         RingBuffer<CrossThreadPool*>::rw_vector vec;
 382         pool_trash.get_read_vector (&vec);
 383
 384         guint deleted = 0;
 385
 386         for (int i = 0; i < 2; ++i) {
 387                 for (guint j = 0; j < vec.len[i]; ++j) {
 388                         if (vec.buf[i][j]->empty()) {
 389                                 delete vec.buf[i][j];
 390                                 ++deleted;
 391                         } else {
 392                                 /* found a non-empty pool, so stop deleting */
 393                                 if (deleted) {
 394                                         pool_trash.increment_read_idx (deleted);
 395                                 }
 396                                 return;
 397                         }
 398                 }
 399         }
 400
 401         if (deleted) {
 402                 pool_trash.increment_read_idx (deleted);
 403         }
 404 }
 405
 406 void
 407 Butler::drop_references ()
 408 {
 409         SessionEvent::pool->set_trash (0);
 410 }
 411
 412
 413 } // namespace ARDOUR
 414