| 1 | /***************************************************************************** |
| 2 | * Copyright (C) 2013 x265 project |
| 3 | * |
| 4 | * Authors: Steve Borho <steve@borho.org> |
| 5 | * |
| 6 | * This program 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 | * This program 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 this program; if not, write to the Free Software |
| 18 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02111, USA. |
| 19 | * |
| 20 | * This program is also available under a commercial proprietary license. |
| 21 | * For more information, contact us at license @ x265.com |
| 22 | *****************************************************************************/ |
| 23 | |
| 24 | #include "common.h" |
| 25 | #include "threadpool.h" |
| 26 | #include "threading.h" |
| 27 | |
| 28 | #include <new> |
| 29 | |
| 30 | #if MACOS |
| 31 | #include <sys/param.h> |
| 32 | #include <sys/sysctl.h> |
| 33 | #endif |
| 34 | |
| 35 | namespace x265 { |
| 36 | // x265 private namespace |
| 37 | |
| 38 | class ThreadPoolImpl; |
| 39 | |
| 40 | class PoolThread : public Thread |
| 41 | { |
| 42 | private: |
| 43 | |
| 44 | ThreadPoolImpl &m_pool; |
| 45 | |
| 46 | PoolThread& operator =(const PoolThread&); |
| 47 | |
| 48 | int m_id; |
| 49 | |
| 50 | bool m_dirty; |
| 51 | |
| 52 | bool m_exited; |
| 53 | |
| 54 | Event m_wakeEvent; |
| 55 | |
| 56 | public: |
| 57 | |
| 58 | PoolThread(ThreadPoolImpl& pool, int id) |
| 59 | : m_pool(pool) |
| 60 | , m_id(id) |
| 61 | , m_dirty(false) |
| 62 | , m_exited(false) |
| 63 | { |
| 64 | } |
| 65 | |
| 66 | bool isDirty() const { return m_dirty; } |
| 67 | |
| 68 | void markDirty() { m_dirty = true; } |
| 69 | |
| 70 | bool isExited() const { return m_exited; } |
| 71 | |
| 72 | void poke() { m_wakeEvent.trigger(); } |
| 73 | |
| 74 | virtual ~PoolThread() {} |
| 75 | |
| 76 | void threadMain(); |
| 77 | }; |
| 78 | |
| 79 | class ThreadPoolImpl : public ThreadPool |
| 80 | { |
| 81 | private: |
| 82 | |
| 83 | bool m_ok; |
| 84 | int m_referenceCount; |
| 85 | int m_numThreads; |
| 86 | int m_numSleepMapWords; |
| 87 | PoolThread *m_threads; |
| 88 | volatile uint32_t *m_sleepMap; |
| 89 | |
| 90 | /* Lock for write access to the provider lists. Threads are |
| 91 | * always allowed to read m_firstProvider and follow the |
| 92 | * linked list. Providers must zero their m_nextProvider |
| 93 | * pointers before removing themselves from this list */ |
| 94 | Lock m_writeLock; |
| 95 | |
| 96 | public: |
| 97 | |
| 98 | static ThreadPoolImpl *s_instance; |
| 99 | static Lock s_createLock; |
| 100 | |
| 101 | JobProvider *m_firstProvider; |
| 102 | JobProvider *m_lastProvider; |
| 103 | |
| 104 | public: |
| 105 | |
| 106 | ThreadPoolImpl(int numthreads); |
| 107 | |
| 108 | virtual ~ThreadPoolImpl(); |
| 109 | |
| 110 | ThreadPoolImpl *AddReference() |
| 111 | { |
| 112 | m_referenceCount++; |
| 113 | |
| 114 | return this; |
| 115 | } |
| 116 | |
| 117 | void markThreadAsleep(int id); |
| 118 | |
| 119 | void waitForAllIdle(); |
| 120 | |
| 121 | int getThreadCount() const { return m_numThreads; } |
| 122 | |
| 123 | bool IsValid() const { return m_ok; } |
| 124 | |
| 125 | void release(); |
| 126 | |
| 127 | void Stop(); |
| 128 | |
| 129 | void enqueueJobProvider(JobProvider &); |
| 130 | |
| 131 | void dequeueJobProvider(JobProvider &); |
| 132 | |
| 133 | void FlushProviderList(); |
| 134 | |
| 135 | void pokeIdleThread(); |
| 136 | }; |
| 137 | |
| 138 | void PoolThread::threadMain() |
| 139 | { |
| 140 | #if _WIN32 |
| 141 | SetThreadPriority(GetCurrentThread(), THREAD_PRIORITY_BELOW_NORMAL); |
| 142 | #else |
| 143 | __attribute__((unused)) int val = nice(10); |
| 144 | #endif |
| 145 | |
| 146 | while (m_pool.IsValid()) |
| 147 | { |
| 148 | /* Walk list of job providers, looking for work */ |
| 149 | JobProvider *cur = m_pool.m_firstProvider; |
| 150 | while (cur) |
| 151 | { |
| 152 | // FindJob() may perform actual work and return true. If |
| 153 | // it does we restart the job search |
| 154 | if (cur->findJob(m_id) == true) |
| 155 | break; |
| 156 | |
| 157 | cur = cur->m_nextProvider; |
| 158 | } |
| 159 | |
| 160 | // this thread has reached the end of the provider list |
| 161 | m_dirty = false; |
| 162 | |
| 163 | if (cur == NULL) |
| 164 | { |
| 165 | m_pool.markThreadAsleep(m_id); |
| 166 | m_wakeEvent.wait(); |
| 167 | } |
| 168 | } |
| 169 | |
| 170 | m_exited = true; |
| 171 | } |
| 172 | |
| 173 | void ThreadPoolImpl::markThreadAsleep(int id) |
| 174 | { |
| 175 | int word = id >> 5; |
| 176 | uint32_t bit = 1 << (id & 31); |
| 177 | |
| 178 | ATOMIC_OR(&m_sleepMap[word], bit); |
| 179 | } |
| 180 | |
| 181 | void ThreadPoolImpl::pokeIdleThread() |
| 182 | { |
| 183 | /* Find a bit in the sleeping thread bitmap and poke it awake, do |
| 184 | * not give up until a thread is awakened or all of them are awake */ |
| 185 | for (int i = 0; i < m_numSleepMapWords; i++) |
| 186 | { |
| 187 | uint32_t oldval = m_sleepMap[i]; |
| 188 | while (oldval) |
| 189 | { |
| 190 | unsigned long id; |
| 191 | CTZ(id, oldval); |
| 192 | |
| 193 | uint32_t bit = 1 << id; |
| 194 | if (ATOMIC_AND(&m_sleepMap[i], ~bit) & bit) |
| 195 | { |
| 196 | m_threads[i * 32 + id].poke(); |
| 197 | return; |
| 198 | } |
| 199 | |
| 200 | oldval = m_sleepMap[i]; |
| 201 | } |
| 202 | } |
| 203 | } |
| 204 | |
| 205 | ThreadPoolImpl *ThreadPoolImpl::s_instance; |
| 206 | Lock ThreadPoolImpl::s_createLock; |
| 207 | |
| 208 | /* static */ |
| 209 | ThreadPool *ThreadPool::allocThreadPool(int numthreads) |
| 210 | { |
| 211 | if (ThreadPoolImpl::s_instance) |
| 212 | return ThreadPoolImpl::s_instance->AddReference(); |
| 213 | |
| 214 | /* acquire the lock to create the instance */ |
| 215 | ThreadPoolImpl::s_createLock.acquire(); |
| 216 | |
| 217 | if (ThreadPoolImpl::s_instance) |
| 218 | /* pool was allocated while we waited for the lock */ |
| 219 | ThreadPoolImpl::s_instance->AddReference(); |
| 220 | else |
| 221 | ThreadPoolImpl::s_instance = new ThreadPoolImpl(numthreads); |
| 222 | ThreadPoolImpl::s_createLock.release(); |
| 223 | |
| 224 | return ThreadPoolImpl::s_instance; |
| 225 | } |
| 226 | |
| 227 | ThreadPool *ThreadPool::getThreadPool() |
| 228 | { |
| 229 | X265_CHECK(ThreadPoolImpl::s_instance, "getThreadPool() called prior to allocThreadPool()\n"); |
| 230 | return ThreadPoolImpl::s_instance; |
| 231 | } |
| 232 | |
| 233 | void ThreadPoolImpl::release() |
| 234 | { |
| 235 | if (--m_referenceCount == 0) |
| 236 | { |
| 237 | X265_CHECK(this == ThreadPoolImpl::s_instance, "multiple thread pool instances detected\n"); |
| 238 | ThreadPoolImpl::s_instance = NULL; |
| 239 | this->Stop(); |
| 240 | delete this; |
| 241 | } |
| 242 | } |
| 243 | |
| 244 | ThreadPoolImpl::ThreadPoolImpl(int numThreads) |
| 245 | : m_ok(false) |
| 246 | , m_referenceCount(1) |
| 247 | , m_firstProvider(NULL) |
| 248 | , m_lastProvider(NULL) |
| 249 | { |
| 250 | m_numSleepMapWords = (numThreads + 31) >> 5; |
| 251 | m_sleepMap = X265_MALLOC(uint32_t, m_numSleepMapWords); |
| 252 | |
| 253 | char *buffer = (char*)X265_MALLOC(PoolThread, numThreads); |
| 254 | m_threads = reinterpret_cast<PoolThread*>(buffer); |
| 255 | m_numThreads = numThreads; |
| 256 | |
| 257 | if (m_threads && m_sleepMap) |
| 258 | { |
| 259 | for (int i = 0; i < m_numSleepMapWords; i++) |
| 260 | m_sleepMap[i] = 0; |
| 261 | |
| 262 | m_ok = true; |
| 263 | int i; |
| 264 | for (i = 0; i < numThreads; i++) |
| 265 | { |
| 266 | new (buffer)PoolThread(*this, i); |
| 267 | buffer += sizeof(PoolThread); |
| 268 | if (!m_threads[i].start()) |
| 269 | { |
| 270 | m_ok = false; |
| 271 | break; |
| 272 | } |
| 273 | } |
| 274 | |
| 275 | if (m_ok) |
| 276 | waitForAllIdle(); |
| 277 | else |
| 278 | { |
| 279 | // stop threads that did start up |
| 280 | for (int j = 0; j < i; j++) |
| 281 | { |
| 282 | m_threads[j].poke(); |
| 283 | m_threads[j].stop(); |
| 284 | } |
| 285 | } |
| 286 | } |
| 287 | } |
| 288 | |
| 289 | void ThreadPoolImpl::waitForAllIdle() |
| 290 | { |
| 291 | if (!m_ok) |
| 292 | return; |
| 293 | |
| 294 | int id = 0; |
| 295 | do |
| 296 | { |
| 297 | int word = id >> 5; |
| 298 | uint32_t bit = 1 << (id & 31); |
| 299 | if (m_sleepMap[word] & bit) |
| 300 | id++; |
| 301 | else |
| 302 | { |
| 303 | GIVE_UP_TIME(); |
| 304 | } |
| 305 | } |
| 306 | while (id < m_numThreads); |
| 307 | } |
| 308 | |
| 309 | void ThreadPoolImpl::Stop() |
| 310 | { |
| 311 | if (m_ok) |
| 312 | { |
| 313 | waitForAllIdle(); |
| 314 | |
| 315 | // set invalid flag, then wake them up so they exit their main func |
| 316 | m_ok = false; |
| 317 | for (int i = 0; i < m_numThreads; i++) |
| 318 | { |
| 319 | m_threads[i].poke(); |
| 320 | m_threads[i].stop(); |
| 321 | } |
| 322 | } |
| 323 | } |
| 324 | |
| 325 | ThreadPoolImpl::~ThreadPoolImpl() |
| 326 | { |
| 327 | X265_FREE((void*)m_sleepMap); |
| 328 | |
| 329 | if (m_threads) |
| 330 | { |
| 331 | // cleanup thread handles |
| 332 | for (int i = 0; i < m_numThreads; i++) |
| 333 | m_threads[i].~PoolThread(); |
| 334 | |
| 335 | X265_FREE(reinterpret_cast<char*>(m_threads)); |
| 336 | } |
| 337 | } |
| 338 | |
| 339 | void ThreadPoolImpl::enqueueJobProvider(JobProvider &p) |
| 340 | { |
| 341 | // only one list writer at a time |
| 342 | ScopedLock l(m_writeLock); |
| 343 | |
| 344 | p.m_nextProvider = NULL; |
| 345 | p.m_prevProvider = m_lastProvider; |
| 346 | m_lastProvider = &p; |
| 347 | |
| 348 | if (p.m_prevProvider) |
| 349 | p.m_prevProvider->m_nextProvider = &p; |
| 350 | else |
| 351 | m_firstProvider = &p; |
| 352 | } |
| 353 | |
| 354 | void ThreadPoolImpl::dequeueJobProvider(JobProvider &p) |
| 355 | { |
| 356 | // only one list writer at a time |
| 357 | ScopedLock l(m_writeLock); |
| 358 | |
| 359 | // update pool entry pointers first |
| 360 | if (m_firstProvider == &p) |
| 361 | m_firstProvider = p.m_nextProvider; |
| 362 | |
| 363 | if (m_lastProvider == &p) |
| 364 | m_lastProvider = p.m_prevProvider; |
| 365 | |
| 366 | // extract self from doubly linked lists |
| 367 | if (p.m_nextProvider) |
| 368 | p.m_nextProvider->m_prevProvider = p.m_prevProvider; |
| 369 | |
| 370 | if (p.m_prevProvider) |
| 371 | p.m_prevProvider->m_nextProvider = p.m_nextProvider; |
| 372 | |
| 373 | p.m_nextProvider = NULL; |
| 374 | p.m_prevProvider = NULL; |
| 375 | } |
| 376 | |
| 377 | /* Ensure all threads have made a full pass through the provider list, ensuring |
| 378 | * dequeued providers are safe for deletion. */ |
| 379 | void ThreadPoolImpl::FlushProviderList() |
| 380 | { |
| 381 | for (int i = 0; i < m_numThreads; i++) |
| 382 | { |
| 383 | m_threads[i].markDirty(); |
| 384 | m_threads[i].poke(); |
| 385 | } |
| 386 | |
| 387 | int i; |
| 388 | do |
| 389 | { |
| 390 | for (i = 0; i < m_numThreads; i++) |
| 391 | { |
| 392 | if (m_threads[i].isDirty()) |
| 393 | { |
| 394 | GIVE_UP_TIME(); |
| 395 | break; |
| 396 | } |
| 397 | } |
| 398 | } |
| 399 | while (i < m_numThreads); |
| 400 | } |
| 401 | |
| 402 | void JobProvider::flush() |
| 403 | { |
| 404 | if (m_nextProvider || m_prevProvider) |
| 405 | dequeue(); |
| 406 | dynamic_cast<ThreadPoolImpl*>(m_pool)->FlushProviderList(); |
| 407 | } |
| 408 | |
| 409 | void JobProvider::enqueue() |
| 410 | { |
| 411 | // Add this provider to the end of the thread pool's job provider list |
| 412 | X265_CHECK(!m_nextProvider && !m_prevProvider && m_pool, "job provider was already queued\n"); |
| 413 | m_pool->enqueueJobProvider(*this); |
| 414 | m_pool->pokeIdleThread(); |
| 415 | } |
| 416 | |
| 417 | void JobProvider::dequeue() |
| 418 | { |
| 419 | // Remove this provider from the thread pool's job provider list |
| 420 | m_pool->dequeueJobProvider(*this); |
| 421 | // Ensure no jobs were missed while the provider was being removed |
| 422 | m_pool->pokeIdleThread(); |
| 423 | } |
| 424 | |
| 425 | int getCpuCount() |
| 426 | { |
| 427 | #if _WIN32 |
| 428 | SYSTEM_INFO sysinfo; |
| 429 | GetSystemInfo(&sysinfo); |
| 430 | return sysinfo.dwNumberOfProcessors; |
| 431 | #elif __unix__ |
| 432 | return sysconf(_SC_NPROCESSORS_ONLN); |
| 433 | #elif MACOS |
| 434 | int nm[2]; |
| 435 | size_t len = 4; |
| 436 | uint32_t count; |
| 437 | |
| 438 | nm[0] = CTL_HW; |
| 439 | nm[1] = HW_AVAILCPU; |
| 440 | sysctl(nm, 2, &count, &len, NULL, 0); |
| 441 | |
| 442 | if (count < 1) |
| 443 | { |
| 444 | nm[1] = HW_NCPU; |
| 445 | sysctl(nm, 2, &count, &len, NULL, 0); |
| 446 | if (count < 1) |
| 447 | count = 1; |
| 448 | } |
| 449 | |
| 450 | return count; |
| 451 | #else // if _WIN32 |
| 452 | return 2; // default to 2 threads, everywhere else |
| 453 | #endif // if _WIN32 |
| 454 | } |
| 455 | } // end namespace x265 |