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/crossfade.h"
  28 #include "ardour/io.h"
  29 #include "ardour/midi_diskstream.h"
  30 #include "ardour/session.h"
  31 #include "ardour/track.h"
  32 #include "ardour/auditioner.h"
  33
  34 #include "i18n.h"
  35
  36 using namespace PBD;
  37
  38 namespace ARDOUR {
  39
  40 Butler::Butler(Session& s)
  41         : SessionHandleRef (s)
  42         , thread(0)
  43         , audio_dstream_capture_buffer_size(0)
  44         , audio_dstream_playback_buffer_size(0)
  45         , midi_dstream_buffer_size(0)
  46         , pool_trash(16)
  47 {
  48         g_atomic_int_set(&should_do_transport_work, 0);
  49         SessionEvent::pool->set_trash (&pool_trash);
  50
  51         Config->ParameterChanged.connect_same_thread (*this, boost::bind (&Butler::config_changed, this, _1));
  52 }
  53
  54 Butler::~Butler()
  55 {
  56         terminate_thread ();
  57 }
  58
  59 void
  60 Butler::config_changed (std::string p)
  61 {
  62         if (p == "playback-buffer-seconds") {
  63                 /* size is in Samples, not bytes */
  64                 audio_dstream_playback_buffer_size = (uint32_t) floor (Config->get_audio_playback_buffer_seconds() * _session.frame_rate());
  65                 _session.adjust_playback_buffering ();
  66         } else if (p == "capture-buffer-seconds") {
  67                 audio_dstream_capture_buffer_size = (uint32_t) floor (Config->get_audio_capture_buffer_seconds() * _session.frame_rate());
  68                 _session.adjust_capture_buffering ();
  69         }
  70 }
  71
  72 int
  73 Butler::start_thread()
  74 {
  75         const float rate = (float)_session.frame_rate();
  76
  77         /* size is in Samples, not bytes */
  78         audio_dstream_capture_buffer_size = (uint32_t) floor (Config->get_audio_capture_buffer_seconds() * rate);
  79         audio_dstream_playback_buffer_size = (uint32_t) floor (Config->get_audio_playback_buffer_seconds() * rate);
  80
  81         /* size is in bytes
  82          * XXX: Jack needs to tell us the MIDI buffer size
  83          * (i.e. how many MIDI bytes we might see in a cycle)
  84          */
  85         midi_dstream_buffer_size = (uint32_t) floor (Config->get_midi_track_buffer_seconds() * rate);
  86
  87         MidiDiskstream::set_readahead_frames ((framecnt_t) (Config->get_midi_readahead() * rate));
  88
  89         Crossfade::set_buffer_size (audio_dstream_playback_buffer_size);
  90
  91         should_run = false;
  92
  93         if (pipe (request_pipe)) {
  94                 error << string_compose(_("Cannot create transport request signal pipe (%1)"),
  95                                 strerror (errno)) << endmsg;
  96                 return -1;
  97         }
  98
  99         if (fcntl (request_pipe[0], F_SETFL, O_NONBLOCK)) {
 100                 error << string_compose(_("UI: cannot set O_NONBLOCK on butler request pipe (%1)"),
 101                                 strerror (errno)) << endmsg;
 102                 return -1;
 103         }
 104
 105         if (fcntl (request_pipe[1], F_SETFL, O_NONBLOCK)) {
 106                 error << string_compose(_("UI: cannot set O_NONBLOCK on butler request pipe (%1)"),
 107                                 strerror (errno)) << endmsg;
 108                 return -1;
 109         }
 110
 111         if (pthread_create_and_store ("disk butler", &thread, _thread_work, this)) {
 112                 error << _("Session: could not create butler thread") << endmsg;
 113                 return -1;
 114         }
 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::Wake:
 183                                                 break;
 184
 185                                         case Request::Run:
 186                                                 should_run = true;
 187                                                 break;
 188
 189                                         case Request::Pause:
 190                                                 should_run = false;
 191                                                 break;
 192
 193                                         case Request::Quit:
 194                                                 pthread_exit_pbd (0);
 195                                                 /*NOTREACHED*/
 196                                                 break;
 197
 198                                         default:
 199                                                 break;
 200                                         }
 201
 202                                 } else if (nread == 0) {
 203                                         break;
 204                                 } else if (errno == EAGAIN) {
 205                                         break;
 206                                 } else {
 207                                         fatal << _("Error reading from butler request pipe") << endmsg;
 208                                         /*NOTREACHED*/
 209                                 }
 210                         }
 211                 }
 212
 213
 214 restart:
 215                 disk_work_outstanding = false;
 216
 217                 if (transport_work_requested()) {
 218                         _session.butler_transport_work ();
 219                 }
 220
 221                 boost::shared_ptr<RouteList> rl = _session.get_routes();
 222
 223                 RouteList rl_with_auditioner = *rl;
 224                 rl_with_auditioner.push_back (_session.the_auditioner());
 225
 226 //              for (i = dsl->begin(); i != dsl->end(); ++i) {
 227 //                      cerr << "BEFORE " << (*i)->name() << ": pb = " << (*i)->playback_buffer_load() << " cp = " << (*i)->capture_buffer_load() << endl;
 228 //              }
 229
 230                 for (i = rl_with_auditioner.begin(); !transport_work_requested() && should_run && i != rl_with_auditioner.end(); ++i) {
 231
 232                         boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 233
 234                         if (!tr) {
 235                                 continue;
 236                         }
 237
 238                         boost::shared_ptr<IO> io = tr->input ();
 239
 240                         if (io && !io->active()) {
 241                                 /* don't read inactive tracks */
 242                                 continue;
 243                         }
 244
 245                         switch (tr->do_refill ()) {
 246                         case 0:
 247                                 break;
 248
 249                         case 1:
 250                                 disk_work_outstanding = true;
 251                                 break;
 252
 253                         default:
 254                                 error << string_compose(_("Butler read ahead failure on dstream %1"), (*i)->name()) << endmsg;
 255                                 break;
 256                         }
 257
 258                 }
 259
 260                 if (i != rl_with_auditioner.begin() && i != rl_with_auditioner.end()) {
 261                         /* we didn't get to all the streams */
 262                         disk_work_outstanding = true;
 263                 }
 264
 265                 if (!err && transport_work_requested()) {
 266                         goto restart;
 267                 }
 268
 269                 for (i = rl->begin(); !transport_work_requested() && should_run && i != rl->end(); ++i) {
 270                         // cerr << "write behind for " << (*i)->name () << endl;
 271
 272                         boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 273
 274                         if (!tr) {
 275                                 continue;
 276                         }
 277
 278                         /* note that we still try to flush diskstreams attached to inactive routes
 279                          */
 280
 281                         switch (tr->do_flush (ButlerContext)) {
 282                         case 0:
 283                                 break;
 284
 285                         case 1:
 286                                 disk_work_outstanding = true;
 287                                 break;
 288
 289                         default:
 290                                 err++;
 291                                 error << string_compose(_("Butler write-behind failure on dstream %1"), (*i)->name()) << endmsg;
 292                                 /* don't break - try to flush all streams in case they
 293                                    are split across disks.
 294                                 */
 295                         }
 296                 }
 297
 298                 if (err && _session.actively_recording()) {
 299                         /* stop the transport and try to catch as much possible
 300                            captured state as we can.
 301                         */
 302                         _session.request_stop ();
 303                 }
 304
 305                 if (i != rl->begin() && i != rl->end()) {
 306                         /* we didn't get to all the streams */
 307                         disk_work_outstanding = true;
 308                 }
 309
 310                 if (!err && transport_work_requested()) {
 311                         goto restart;
 312                 }
 313
 314                 if (!disk_work_outstanding) {
 315                         _session.refresh_disk_space ();
 316                 }
 317
 318
 319                 {
 320                         Glib::Mutex::Lock lm (request_lock);
 321
 322                         if (should_run && (disk_work_outstanding || transport_work_requested())) {
 323 //                              for (DiskstreamList::iterator i = dsl->begin(); i != dsl->end(); ++i) {
 324 //                                      cerr << "AFTER " << (*i)->name() << ": pb = " << (*i)->playback_buffer_load() << " cp = " << (*i)->capture_buffer_load() << endl;
 325 //                              }
 326
 327                                 goto restart;
 328                         }
 329
 330                         paused.signal();
 331                 }
 332
 333                 empty_pool_trash ();
 334         }
 335
 336         pthread_exit_pbd (0);
 337         /*NOTREACHED*/
 338         return (0);
 339 }
 340
 341 void
 342 Butler::schedule_transport_work ()
 343 {
 344         g_atomic_int_inc (&should_do_transport_work);
 345         summon ();
 346 }
 347
 348 void
 349 Butler::summon ()
 350 {
 351         char c = Request::Run;
 352         (void) ::write (request_pipe[1], &c, 1);
 353 }
 354
 355 void
 356 Butler::stop ()
 357 {
 358         Glib::Mutex::Lock lm (request_lock);
 359         char c = Request::Pause;
 360         (void) ::write (request_pipe[1], &c, 1);
 361         paused.wait(request_lock);
 362 }
 363
 364 void
 365 Butler::wait_until_finished ()
 366 {
 367         Glib::Mutex::Lock lm (request_lock);
 368         char c = Request::Wake;
 369         (void) ::write (request_pipe[1], &c, 1);
 370         paused.wait(request_lock);
 371 }
 372
 373 bool
 374 Butler::transport_work_requested () const
 375 {
 376         return g_atomic_int_get(&should_do_transport_work);
 377 }
 378
 379 void
 380 Butler::empty_pool_trash ()
 381 {
 382         /* look in the trash, deleting empty pools until we come to one that is not empty */
 383
 384         RingBuffer<CrossThreadPool*>::rw_vector vec;
 385         pool_trash.get_read_vector (&vec);
 386
 387         guint deleted = 0;
 388
 389         for (int i = 0; i < 2; ++i) {
 390                 for (guint j = 0; j < vec.len[i]; ++j) {
 391                         if (vec.buf[i][j]->empty()) {
 392                                 delete vec.buf[i][j];
 393                                 ++deleted;
 394                         } else {
 395                                 /* found a non-empty pool, so stop deleting */
 396                                 if (deleted) {
 397                                         pool_trash.increment_read_idx (deleted);
 398                                 }
 399                                 return;
 400                         }
 401                 }
 402         }
 403
 404         if (deleted) {
 405                 pool_trash.increment_read_idx (deleted);
 406         }
 407 }
 408
 409 void
 410 Butler::drop_references ()
 411 {
 412         SessionEvent::pool->set_trash (0);
 413 }
 414
 415
 416 } // namespace ARDOUR
 417