src/lib/job_manager.cc

   1 /*
   2     Copyright (C) 2012-2018 Carl Hetherington <cth@carlh.net>
   3
   4     This file is part of DCP-o-matic.
   5
   6     DCP-o-matic is free software; you can redistribute it and/or modify
   7     it under the terms of the GNU General Public License as published by
   8     the Free Software Foundation; either version 2 of the License, or
   9     (at your option) any later version.
  10
  11     DCP-o-matic is distributed in the hope that it will be useful,
  12     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14     GNU General Public License for more details.
  15
  16     You should have received a copy of the GNU General Public License
  17     along with DCP-o-matic.  If not, see <http://www.gnu.org/licenses/>.
  18
  19 */
  20
  21 /** @file  src/job_manager.cc
  22  *  @brief A simple scheduler for jobs.
  23  */
  24
  25 #include "job_manager.h"
  26 #include "job.h"
  27 #include "cross.h"
  28 #include "analyse_audio_job.h"
  29 #include "film.h"
  30 #include <boost/thread.hpp>
  31 #include <boost/foreach.hpp>
  32 #include <iostream>
  33
  34 using std::string;
  35 using std::list;
  36 using std::cout;
  37 using boost::shared_ptr;
  38 using boost::weak_ptr;
  39 using boost::function;
  40 using boost::dynamic_pointer_cast;
  41 using boost::optional;
  42 using boost::bind;
  43
  44 JobManager* JobManager::_instance = 0;
  45
  46 JobManager::JobManager ()
  47         : _terminate (false)
  48         , _paused (false)
  49         , _scheduler (0)
  50 {
  51
  52 }
  53
  54 void
  55 JobManager::start ()
  56 {
  57         _scheduler = new boost::thread (boost::bind (&JobManager::scheduler, this));
  58 #ifdef DCPOMATIC_LINUX
  59         pthread_setname_np (_scheduler->native_handle(), "job-scheduler");
  60 #endif
  61 }
  62
  63 JobManager::~JobManager ()
  64 {
  65         BOOST_FOREACH (boost::signals2::connection& i, _connections) {
  66                 i.disconnect ();
  67         }
  68
  69         {
  70                 boost::mutex::scoped_lock lm (_mutex);
  71                 _terminate = true;
  72                 _empty_condition.notify_all ();
  73         }
  74
  75         if (_scheduler) {
  76                 /* Ideally this would be a DCPOMATIC_ASSERT(_scheduler->joinable()) but we
  77                    can't throw exceptions from a destructor.
  78                 */
  79                 if (_scheduler->joinable ()) {
  80                         _scheduler->join ();
  81                 }
  82         }
  83
  84         delete _scheduler;
  85 }
  86
  87 shared_ptr<Job>
  88 JobManager::add (shared_ptr<Job> j)
  89 {
  90         {
  91                 boost::mutex::scoped_lock lm (_mutex);
  92                 _jobs.push_back (j);
  93                 _empty_condition.notify_all ();
  94         }
  95
  96         emit (boost::bind (boost::ref (JobAdded), weak_ptr<Job> (j)));
  97
  98         return j;
  99 }
 100
 101 shared_ptr<Job>
 102 JobManager::add_after (shared_ptr<Job> after, shared_ptr<Job> j)
 103 {
 104         {
 105                 boost::mutex::scoped_lock lm (_mutex);
 106                 list<shared_ptr<Job> >::iterator i = find (_jobs.begin(), _jobs.end(), after);
 107                 DCPOMATIC_ASSERT (i != _jobs.end());
 108                 _jobs.insert (i, j);
 109                 _empty_condition.notify_all ();
 110         }
 111
 112         emit (boost::bind (boost::ref (JobAdded), weak_ptr<Job> (j)));
 113
 114         return j;
 115 }
 116
 117 list<shared_ptr<Job> >
 118 JobManager::get () const
 119 {
 120         boost::mutex::scoped_lock lm (_mutex);
 121         return _jobs;
 122 }
 123
 124 bool
 125 JobManager::work_to_do () const
 126 {
 127         boost::mutex::scoped_lock lm (_mutex);
 128         list<shared_ptr<Job> >::const_iterator i = _jobs.begin();
 129         while (i != _jobs.end() && (*i)->finished()) {
 130                 ++i;
 131         }
 132
 133         return i != _jobs.end ();
 134 }
 135
 136 bool
 137 JobManager::errors () const
 138 {
 139         boost::mutex::scoped_lock lm (_mutex);
 140         BOOST_FOREACH (shared_ptr<Job> i, _jobs) {
 141                 if (i->finished_in_error ()) {
 142                         return true;
 143                 }
 144         }
 145
 146         return false;
 147 }
 148
 149 void
 150 JobManager::scheduler ()
 151 {
 152         while (true) {
 153
 154                 boost::mutex::scoped_lock lm (_mutex);
 155
 156                 optional<string> active_job;
 157
 158                 while (true) {
 159                         bool have_new = false;
 160                         bool have_running = false;
 161                         BOOST_FOREACH (shared_ptr<Job> i, _jobs) {
 162                                 if (i->running()) {
 163                                         have_running = true;
 164                                         active_job = i->json_name();
 165                                 }
 166                                 if (i->is_new()) {
 167                                         have_new = true;
 168                                 }
 169                         }
 170
 171                         if ((!have_running && have_new) || _terminate) {
 172                                 break;
 173                         }
 174
 175                         _empty_condition.wait (lm);
 176                 }
 177
 178                 if (_terminate) {
 179                         break;
 180                 }
 181
 182                 BOOST_FOREACH (shared_ptr<Job> i, _jobs) {
 183                         if (i->is_new()) {
 184                                 _connections.push_back (i->FinishedImmediate.connect(bind(&JobManager::job_finished, this)));
 185                                 i->start ();
 186                                 /* Only start one job at once */
 187                                 break;
 188                         }
 189                 }
 190
 191                 lm.unlock ();
 192
 193                 if (active_job != _last_active_job) {
 194                         emit (boost::bind (boost::ref (ActiveJobsChanged), _last_active_job, active_job));
 195                         _last_active_job = active_job;
 196                 }
 197         }
 198 }
 199
 200 void
 201 JobManager::job_finished ()
 202 {
 203         _empty_condition.notify_all ();
 204 }
 205
 206 JobManager *
 207 JobManager::instance ()
 208 {
 209         if (_instance == 0) {
 210                 _instance = new JobManager ();
 211                 _instance->start ();
 212         }
 213
 214         return _instance;
 215 }
 216
 217 void
 218 JobManager::drop ()
 219 {
 220         delete _instance;
 221         _instance = 0;
 222 }
 223
 224 void
 225 JobManager::analyse_audio (
 226         shared_ptr<const Film> film,
 227         shared_ptr<const Playlist> playlist,
 228         bool from_zero,
 229         boost::signals2::connection& connection,
 230         function<void()> ready
 231         )
 232 {
 233         {
 234                 boost::mutex::scoped_lock lm (_mutex);
 235
 236                 BOOST_FOREACH (shared_ptr<Job> i, _jobs) {
 237                         shared_ptr<AnalyseAudioJob> a = dynamic_pointer_cast<AnalyseAudioJob> (i);
 238                         if (a && a->playlist () == playlist) {
 239                                 i->when_finished (connection, ready);
 240                                 return;
 241                         }
 242                 }
 243         }
 244
 245         shared_ptr<AnalyseAudioJob> job;
 246
 247         {
 248                 boost::mutex::scoped_lock lm (_mutex);
 249
 250                 job.reset (new AnalyseAudioJob (film, playlist, from_zero));
 251                 connection = job->Finished.connect (ready);
 252                 _jobs.push_back (job);
 253                 _empty_condition.notify_all ();
 254         }
 255
 256         emit (boost::bind (boost::ref (JobAdded), weak_ptr<Job> (job)));
 257 }
 258
 259 void
 260 JobManager::increase_priority (shared_ptr<Job> job)
 261 {
 262         bool changed = false;
 263
 264         {
 265                 boost::mutex::scoped_lock lm (_mutex);
 266                 list<shared_ptr<Job> >::iterator last = _jobs.end ();
 267                 for (list<shared_ptr<Job> >::iterator i = _jobs.begin(); i != _jobs.end(); ++i) {
 268                         if (*i == job && last != _jobs.end()) {
 269                                 swap (*i, *last);
 270                                 changed = true;
 271                                 break;
 272                         }
 273                         last = i;
 274                 }
 275         }
 276
 277         if (changed) {
 278                 priority_changed ();
 279         }
 280 }
 281
 282 void
 283 JobManager::priority_changed ()
 284 {
 285         {
 286                 boost::mutex::scoped_lock lm (_mutex);
 287
 288                 bool first = true;
 289                 BOOST_FOREACH (shared_ptr<Job> i, _jobs) {
 290                         if (first) {
 291                                 if (i->is_new ()) {
 292                                         i->start ();
 293                                 } else if (i->paused_by_priority ()) {
 294                                         i->resume ();
 295                                 }
 296                                 first = false;
 297                         } else {
 298                                 if (i->running ()) {
 299                                         i->pause_by_priority ();
 300                                 }
 301                         }
 302                 }
 303         }
 304
 305         emit (boost::bind (boost::ref (JobsReordered)));
 306 }
 307
 308 void
 309 JobManager::decrease_priority (shared_ptr<Job> job)
 310 {
 311         bool changed = false;
 312
 313         {
 314                 boost::mutex::scoped_lock lm (_mutex);
 315                 for (list<shared_ptr<Job> >::iterator i = _jobs.begin(); i != _jobs.end(); ++i) {
 316                         list<shared_ptr<Job> >::iterator next = i;
 317                         ++next;
 318                         if (*i == job && next != _jobs.end()) {
 319                                 swap (*i, *next);
 320                                 changed = true;
 321                                 break;
 322                         }
 323                 }
 324         }
 325
 326         if (changed) {
 327                 priority_changed ();
 328         }
 329 }
 330
 331 void
 332 JobManager::pause ()
 333 {
 334         boost::mutex::scoped_lock lm (_mutex);
 335
 336         if (_paused) {
 337                 return;
 338         }
 339
 340         BOOST_FOREACH (shared_ptr<Job> i, _jobs) {
 341                 if (i->pause_by_user()) {
 342                         _paused_job = i;
 343                 }
 344         }
 345
 346         _paused = true;
 347 }
 348
 349 void
 350 JobManager::resume ()
 351 {
 352         boost::mutex::scoped_lock lm (_mutex);
 353         if (!_paused) {
 354                 return;
 355         }
 356
 357         if (_paused_job) {
 358                 _paused_job->resume ();
 359         }
 360
 361         _paused_job.reset ();
 362         _paused = false;
 363 }