FastMixer.cpp revision 0d27c65ddb5c968baa6db0c26e80f5c451bc52bc
1/* 2 * Copyright (C) 2012 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17#define LOG_TAG "FastMixer" 18//#define LOG_NDEBUG 0 19 20#include <sys/atomics.h> 21#include <time.h> 22#include <utils/Log.h> 23#include <utils/Trace.h> 24#include <system/audio.h> 25#ifdef FAST_MIXER_STATISTICS 26#include <cpustats/CentralTendencyStatistics.h> 27#ifdef CPU_FREQUENCY_STATISTICS 28#include <cpustats/ThreadCpuUsage.h> 29#endif 30#endif 31#include "AudioMixer.h" 32#include "FastMixer.h" 33 34#define FAST_HOT_IDLE_NS 1000000L // 1 ms: time to sleep while hot idling 35#define FAST_DEFAULT_NS 999999999L // ~1 sec: default time to sleep 36#define MIN_WARMUP_CYCLES 2 // minimum number of loop cycles to wait for warmup 37#define MAX_WARMUP_CYCLES 10 // maximum number of loop cycles to wait for warmup 38 39namespace android { 40 41// Fast mixer thread 42bool FastMixer::threadLoop() 43{ 44 static const FastMixerState initial; 45 const FastMixerState *previous = &initial, *current = &initial; 46 FastMixerState preIdle; // copy of state before we went into idle 47 struct timespec oldTs = {0, 0}; 48 bool oldTsValid = false; 49 long slopNs = 0; // accumulated time we've woken up too early (> 0) or too late (< 0) 50 long sleepNs = -1; // -1: busy wait, 0: sched_yield, > 0: nanosleep 51 int fastTrackNames[FastMixerState::kMaxFastTracks]; // handles used by mixer to identify tracks 52 int generations[FastMixerState::kMaxFastTracks]; // last observed mFastTracks[i].mGeneration 53 unsigned i; 54 for (i = 0; i < FastMixerState::kMaxFastTracks; ++i) { 55 fastTrackNames[i] = -1; 56 generations[i] = 0; 57 } 58 NBAIO_Sink *outputSink = NULL; 59 int outputSinkGen = 0; 60 AudioMixer* mixer = NULL; 61 short *mixBuffer = NULL; 62 enum {UNDEFINED, MIXED, ZEROED} mixBufferState = UNDEFINED; 63 NBAIO_Format format = Format_Invalid; 64 unsigned sampleRate = 0; 65 int fastTracksGen = 0; 66 long periodNs = 0; // expected period; the time required to render one mix buffer 67 long underrunNs = 0; // underrun likely when write cycle is greater than this value 68 long overrunNs = 0; // overrun likely when write cycle is less than this value 69 long forceNs = 0; // if overrun detected, force the write cycle to take this much time 70 long warmupNs = 0; // warmup complete when write cycle is greater than to this value 71 FastMixerDumpState dummyDumpState, *dumpState = &dummyDumpState; 72 bool ignoreNextOverrun = true; // used to ignore initial overrun and first after an underrun 73#ifdef FAST_MIXER_STATISTICS 74 struct timespec oldLoad = {0, 0}; // previous value of clock_gettime(CLOCK_THREAD_CPUTIME_ID) 75 bool oldLoadValid = false; // whether oldLoad is valid 76 uint32_t bounds = 0; 77 bool full = false; // whether we have collected at least kSamplingN samples 78#ifdef CPU_FREQUENCY_STATISTICS 79 ThreadCpuUsage tcu; // for reading the current CPU clock frequency in kHz 80#endif 81#endif 82 unsigned coldGen = 0; // last observed mColdGen 83 bool isWarm = false; // true means ready to mix, false means wait for warmup before mixing 84 struct timespec measuredWarmupTs = {0, 0}; // how long did it take for warmup to complete 85 uint32_t warmupCycles = 0; // counter of number of loop cycles required to warmup 86 NBAIO_Sink* teeSink = NULL; // if non-NULL, then duplicate write() to this non-blocking sink 87 88 for (;;) { 89 90 // either nanosleep, sched_yield, or busy wait 91 if (sleepNs >= 0) { 92 if (sleepNs > 0) { 93 ALOG_ASSERT(sleepNs < 1000000000); 94 const struct timespec req = {0, sleepNs}; 95 nanosleep(&req, NULL); 96 } else { 97 sched_yield(); 98 } 99 } 100 // default to long sleep for next cycle 101 sleepNs = FAST_DEFAULT_NS; 102 103 // poll for state change 104 const FastMixerState *next = mSQ.poll(); 105 if (next == NULL) { 106 // continue to use the default initial state until a real state is available 107 ALOG_ASSERT(current == &initial && previous == &initial); 108 next = current; 109 } 110 111 FastMixerState::Command command = next->mCommand; 112 if (next != current) { 113 114 // As soon as possible of learning of a new dump area, start using it 115 dumpState = next->mDumpState != NULL ? next->mDumpState : &dummyDumpState; 116 teeSink = next->mTeeSink; 117 118 // We want to always have a valid reference to the previous (non-idle) state. 119 // However, the state queue only guarantees access to current and previous states. 120 // So when there is a transition from a non-idle state into an idle state, we make a 121 // copy of the last known non-idle state so it is still available on return from idle. 122 // The possible transitions are: 123 // non-idle -> non-idle update previous from current in-place 124 // non-idle -> idle update previous from copy of current 125 // idle -> idle don't update previous 126 // idle -> non-idle don't update previous 127 if (!(current->mCommand & FastMixerState::IDLE)) { 128 if (command & FastMixerState::IDLE) { 129 preIdle = *current; 130 current = &preIdle; 131 oldTsValid = false; 132 oldLoadValid = false; 133 ignoreNextOverrun = true; 134 } 135 previous = current; 136 } 137 current = next; 138 } 139#if !LOG_NDEBUG 140 next = NULL; // not referenced again 141#endif 142 143 dumpState->mCommand = command; 144 145 switch (command) { 146 case FastMixerState::INITIAL: 147 case FastMixerState::HOT_IDLE: 148 sleepNs = FAST_HOT_IDLE_NS; 149 continue; 150 case FastMixerState::COLD_IDLE: 151 // only perform a cold idle command once 152 // FIXME consider checking previous state and only perform if previous != COLD_IDLE 153 if (current->mColdGen != coldGen) { 154 int32_t *coldFutexAddr = current->mColdFutexAddr; 155 ALOG_ASSERT(coldFutexAddr != NULL); 156 int32_t old = android_atomic_dec(coldFutexAddr); 157 if (old <= 0) { 158 __futex_syscall4(coldFutexAddr, FUTEX_WAIT_PRIVATE, old - 1, NULL); 159 } 160 // This may be overly conservative; there could be times that the normal mixer 161 // requests such a brief cold idle that it doesn't require resetting this flag. 162 isWarm = false; 163 measuredWarmupTs.tv_sec = 0; 164 measuredWarmupTs.tv_nsec = 0; 165 warmupCycles = 0; 166 sleepNs = -1; 167 coldGen = current->mColdGen; 168 bounds = 0; 169 full = false; 170 oldTsValid = !clock_gettime(CLOCK_MONOTONIC, &oldTs); 171 } else { 172 sleepNs = FAST_HOT_IDLE_NS; 173 } 174 continue; 175 case FastMixerState::EXIT: 176 delete mixer; 177 delete[] mixBuffer; 178 return false; 179 case FastMixerState::MIX: 180 case FastMixerState::WRITE: 181 case FastMixerState::MIX_WRITE: 182 break; 183 default: 184 LOG_FATAL("bad command %d", command); 185 } 186 187 // there is a non-idle state available to us; did the state change? 188 size_t frameCount = current->mFrameCount; 189 if (current != previous) { 190 191 // handle state change here, but since we want to diff the state, 192 // we're prepared for previous == &initial the first time through 193 unsigned previousTrackMask; 194 195 // check for change in output HAL configuration 196 NBAIO_Format previousFormat = format; 197 if (current->mOutputSinkGen != outputSinkGen) { 198 outputSink = current->mOutputSink; 199 outputSinkGen = current->mOutputSinkGen; 200 if (outputSink == NULL) { 201 format = Format_Invalid; 202 sampleRate = 0; 203 } else { 204 format = outputSink->format(); 205 sampleRate = Format_sampleRate(format); 206 ALOG_ASSERT(Format_channelCount(format) == 2); 207 } 208 dumpState->mSampleRate = sampleRate; 209 } 210 211 if ((format != previousFormat) || (frameCount != previous->mFrameCount)) { 212 // FIXME to avoid priority inversion, don't delete here 213 delete mixer; 214 mixer = NULL; 215 delete[] mixBuffer; 216 mixBuffer = NULL; 217 if (frameCount > 0 && sampleRate > 0) { 218 // FIXME new may block for unbounded time at internal mutex of the heap 219 // implementation; it would be better to have normal mixer allocate for us 220 // to avoid blocking here and to prevent possible priority inversion 221 mixer = new AudioMixer(frameCount, sampleRate, FastMixerState::kMaxFastTracks); 222 mixBuffer = new short[frameCount * 2]; 223 periodNs = (frameCount * 1000000000LL) / sampleRate; // 1.00 224 underrunNs = (frameCount * 1750000000LL) / sampleRate; // 1.75 225 overrunNs = (frameCount * 500000000LL) / sampleRate; // 0.50 226 forceNs = (frameCount * 950000000LL) / sampleRate; // 0.95 227 warmupNs = (frameCount * 500000000LL) / sampleRate; // 0.50 228 } else { 229 periodNs = 0; 230 underrunNs = 0; 231 overrunNs = 0; 232 forceNs = 0; 233 warmupNs = 0; 234 } 235 mixBufferState = UNDEFINED; 236#if !LOG_NDEBUG 237 for (i = 0; i < FastMixerState::kMaxFastTracks; ++i) { 238 fastTrackNames[i] = -1; 239 } 240#endif 241 // we need to reconfigure all active tracks 242 previousTrackMask = 0; 243 fastTracksGen = current->mFastTracksGen - 1; 244 dumpState->mFrameCount = frameCount; 245 } else { 246 previousTrackMask = previous->mTrackMask; 247 } 248 249 // check for change in active track set 250 unsigned currentTrackMask = current->mTrackMask; 251 dumpState->mTrackMask = currentTrackMask; 252 if (current->mFastTracksGen != fastTracksGen) { 253 ALOG_ASSERT(mixBuffer != NULL); 254 int name; 255 256 // process removed tracks first to avoid running out of track names 257 unsigned removedTracks = previousTrackMask & ~currentTrackMask; 258 while (removedTracks != 0) { 259 i = __builtin_ctz(removedTracks); 260 removedTracks &= ~(1 << i); 261 const FastTrack* fastTrack = ¤t->mFastTracks[i]; 262 ALOG_ASSERT(fastTrack->mBufferProvider == NULL); 263 if (mixer != NULL) { 264 name = fastTrackNames[i]; 265 ALOG_ASSERT(name >= 0); 266 mixer->deleteTrackName(name); 267 } 268#if !LOG_NDEBUG 269 fastTrackNames[i] = -1; 270#endif 271 // don't reset track dump state, since other side is ignoring it 272 generations[i] = fastTrack->mGeneration; 273 } 274 275 // now process added tracks 276 unsigned addedTracks = currentTrackMask & ~previousTrackMask; 277 while (addedTracks != 0) { 278 i = __builtin_ctz(addedTracks); 279 addedTracks &= ~(1 << i); 280 const FastTrack* fastTrack = ¤t->mFastTracks[i]; 281 AudioBufferProvider *bufferProvider = fastTrack->mBufferProvider; 282 ALOG_ASSERT(bufferProvider != NULL && fastTrackNames[i] == -1); 283 if (mixer != NULL) { 284 // calling getTrackName with default channel mask 285 name = mixer->getTrackName(AUDIO_CHANNEL_OUT_STEREO); 286 ALOG_ASSERT(name >= 0); 287 fastTrackNames[i] = name; 288 mixer->setBufferProvider(name, bufferProvider); 289 mixer->setParameter(name, AudioMixer::TRACK, AudioMixer::MAIN_BUFFER, 290 (void *) mixBuffer); 291 // newly allocated track names default to full scale volume 292 if (fastTrack->mSampleRate != 0 && fastTrack->mSampleRate != sampleRate) { 293 mixer->setParameter(name, AudioMixer::RESAMPLE, 294 AudioMixer::SAMPLE_RATE, (void*) fastTrack->mSampleRate); 295 } 296 mixer->setParameter(name, AudioMixer::TRACK, AudioMixer::CHANNEL_MASK, 297 (void *) fastTrack->mChannelMask); 298 mixer->enable(name); 299 } 300 generations[i] = fastTrack->mGeneration; 301 } 302 303 // finally process modified tracks; these use the same slot 304 // but may have a different buffer provider or volume provider 305 unsigned modifiedTracks = currentTrackMask & previousTrackMask; 306 while (modifiedTracks != 0) { 307 i = __builtin_ctz(modifiedTracks); 308 modifiedTracks &= ~(1 << i); 309 const FastTrack* fastTrack = ¤t->mFastTracks[i]; 310 if (fastTrack->mGeneration != generations[i]) { 311 AudioBufferProvider *bufferProvider = fastTrack->mBufferProvider; 312 ALOG_ASSERT(bufferProvider != NULL); 313 if (mixer != NULL) { 314 name = fastTrackNames[i]; 315 ALOG_ASSERT(name >= 0); 316 mixer->setBufferProvider(name, bufferProvider); 317 if (fastTrack->mVolumeProvider == NULL) { 318 mixer->setParameter(name, AudioMixer::VOLUME, AudioMixer::VOLUME0, 319 (void *)0x1000); 320 mixer->setParameter(name, AudioMixer::VOLUME, AudioMixer::VOLUME1, 321 (void *)0x1000); 322 } 323 if (fastTrack->mSampleRate != 0 && 324 fastTrack->mSampleRate != sampleRate) { 325 mixer->setParameter(name, AudioMixer::RESAMPLE, 326 AudioMixer::SAMPLE_RATE, (void*) fastTrack->mSampleRate); 327 } else { 328 mixer->setParameter(name, AudioMixer::RESAMPLE, 329 AudioMixer::REMOVE, NULL); 330 } 331 mixer->setParameter(name, AudioMixer::TRACK, AudioMixer::CHANNEL_MASK, 332 (void *) fastTrack->mChannelMask); 333 // already enabled 334 } 335 generations[i] = fastTrack->mGeneration; 336 } 337 } 338 339 fastTracksGen = current->mFastTracksGen; 340 341 dumpState->mNumTracks = popcount(currentTrackMask); 342 } 343 344#if 1 // FIXME shouldn't need this 345 // only process state change once 346 previous = current; 347#endif 348 } 349 350 // do work using current state here 351 if ((command & FastMixerState::MIX) && (mixer != NULL) && isWarm) { 352 ALOG_ASSERT(mixBuffer != NULL); 353 // for each track, update volume and check for underrun 354 unsigned currentTrackMask = current->mTrackMask; 355 while (currentTrackMask != 0) { 356 i = __builtin_ctz(currentTrackMask); 357 currentTrackMask &= ~(1 << i); 358 const FastTrack* fastTrack = ¤t->mFastTracks[i]; 359 int name = fastTrackNames[i]; 360 ALOG_ASSERT(name >= 0); 361 if (fastTrack->mVolumeProvider != NULL) { 362 uint32_t vlr = fastTrack->mVolumeProvider->getVolumeLR(); 363 mixer->setParameter(name, AudioMixer::VOLUME, AudioMixer::VOLUME0, 364 (void *)(vlr & 0xFFFF)); 365 mixer->setParameter(name, AudioMixer::VOLUME, AudioMixer::VOLUME1, 366 (void *)(vlr >> 16)); 367 } 368 // FIXME The current implementation of framesReady() for fast tracks 369 // takes a tryLock, which can block 370 // up to 1 ms. If enough active tracks all blocked in sequence, this would result 371 // in the overall fast mix cycle being delayed. Should use a non-blocking FIFO. 372 size_t framesReady = fastTrack->mBufferProvider->framesReady(); 373#if defined(ATRACE_TAG) && (ATRACE_TAG != ATRACE_TAG_NEVER) 374 // I wish we had formatted trace names 375 char traceName[16]; 376 strcpy(traceName, "framesReady"); 377 traceName[11] = i + (i < 10 ? '0' : 'A' - 10); 378 traceName[12] = '\0'; 379 ATRACE_INT(traceName, framesReady); 380#endif 381 FastTrackDump *ftDump = &dumpState->mTracks[i]; 382 FastTrackUnderruns underruns = ftDump->mUnderruns; 383 if (framesReady < frameCount) { 384 if (framesReady == 0) { 385 underruns.mBitFields.mEmpty++; 386 underruns.mBitFields.mMostRecent = UNDERRUN_EMPTY; 387 mixer->disable(name); 388 } else { 389 // allow mixing partial buffer 390 underruns.mBitFields.mPartial++; 391 underruns.mBitFields.mMostRecent = UNDERRUN_PARTIAL; 392 mixer->enable(name); 393 } 394 } else { 395 underruns.mBitFields.mFull++; 396 underruns.mBitFields.mMostRecent = UNDERRUN_FULL; 397 mixer->enable(name); 398 } 399 ftDump->mUnderruns = underruns; 400 ftDump->mFramesReady = framesReady; 401 } 402 403 int64_t pts; 404 if (outputSink == NULL || (OK != outputSink->getNextWriteTimestamp(&pts))) 405 pts = AudioBufferProvider::kInvalidPTS; 406 407 // process() is CPU-bound 408 mixer->process(pts); 409 mixBufferState = MIXED; 410 } else if (mixBufferState == MIXED) { 411 mixBufferState = UNDEFINED; 412 } 413 bool attemptedWrite = false; 414 //bool didFullWrite = false; // dumpsys could display a count of partial writes 415 if ((command & FastMixerState::WRITE) && (outputSink != NULL) && (mixBuffer != NULL)) { 416 if (mixBufferState == UNDEFINED) { 417 memset(mixBuffer, 0, frameCount * 2 * sizeof(short)); 418 mixBufferState = ZEROED; 419 } 420 if (teeSink != NULL) { 421 (void) teeSink->write(mixBuffer, frameCount); 422 } 423 // FIXME write() is non-blocking and lock-free for a properly implemented NBAIO sink, 424 // but this code should be modified to handle both non-blocking and blocking sinks 425 dumpState->mWriteSequence++; 426#if defined(ATRACE_TAG) && (ATRACE_TAG != ATRACE_TAG_NEVER) 427 Tracer::traceBegin(ATRACE_TAG, "write"); 428#endif 429 ssize_t framesWritten = outputSink->write(mixBuffer, frameCount); 430#if defined(ATRACE_TAG) && (ATRACE_TAG != ATRACE_TAG_NEVER) 431 Tracer::traceEnd(ATRACE_TAG); 432#endif 433 dumpState->mWriteSequence++; 434 if (framesWritten >= 0) { 435 ALOG_ASSERT(framesWritten <= frameCount); 436 dumpState->mFramesWritten += framesWritten; 437 //if ((size_t) framesWritten == frameCount) { 438 // didFullWrite = true; 439 //} 440 } else { 441 dumpState->mWriteErrors++; 442 } 443 attemptedWrite = true; 444 // FIXME count # of writes blocked excessively, CPU usage, etc. for dump 445 } 446 447 // To be exactly periodic, compute the next sleep time based on current time. 448 // This code doesn't have long-term stability when the sink is non-blocking. 449 // FIXME To avoid drift, use the local audio clock or watch the sink's fill status. 450 struct timespec newTs; 451 int rc = clock_gettime(CLOCK_MONOTONIC, &newTs); 452 if (rc == 0) { 453 if (oldTsValid) { 454 time_t sec = newTs.tv_sec - oldTs.tv_sec; 455 long nsec = newTs.tv_nsec - oldTs.tv_nsec; 456 if (nsec < 0) { 457 --sec; 458 nsec += 1000000000; 459 } 460 // To avoid an initial underrun on fast tracks after exiting standby, 461 // do not start pulling data from tracks and mixing until warmup is complete. 462 // Warmup is considered complete after the earlier of: 463 // MIN_WARMUP_CYCLES write() attempts and last one blocks for at least warmupNs 464 // MAX_WARMUP_CYCLES write() attempts. 465 // This is overly conservative, but to get better accuracy requires a new HAL API. 466 if (!isWarm && attemptedWrite) { 467 measuredWarmupTs.tv_sec += sec; 468 measuredWarmupTs.tv_nsec += nsec; 469 if (measuredWarmupTs.tv_nsec >= 1000000000) { 470 measuredWarmupTs.tv_sec++; 471 measuredWarmupTs.tv_nsec -= 1000000000; 472 } 473 ++warmupCycles; 474 if ((nsec > warmupNs && warmupCycles >= MIN_WARMUP_CYCLES) || 475 (warmupCycles >= MAX_WARMUP_CYCLES)) { 476 isWarm = true; 477 dumpState->mMeasuredWarmupTs = measuredWarmupTs; 478 dumpState->mWarmupCycles = warmupCycles; 479 } 480 } 481 sleepNs = -1; 482 if (isWarm) { 483 if (sec > 0 || nsec > underrunNs) { 484#if defined(ATRACE_TAG) && (ATRACE_TAG != ATRACE_TAG_NEVER) 485 ScopedTrace st(ATRACE_TAG, "underrun"); 486#endif 487 // FIXME only log occasionally 488 ALOGV("underrun: time since last cycle %d.%03ld sec", 489 (int) sec, nsec / 1000000L); 490 dumpState->mUnderruns++; 491 ignoreNextOverrun = true; 492 } else if (nsec < overrunNs) { 493 if (ignoreNextOverrun) { 494 ignoreNextOverrun = false; 495 } else { 496 // FIXME only log occasionally 497 ALOGV("overrun: time since last cycle %d.%03ld sec", 498 (int) sec, nsec / 1000000L); 499 dumpState->mOverruns++; 500 } 501 // This forces a minimum cycle time. It: 502 // - compensates for an audio HAL with jitter due to sample rate conversion 503 // - works with a variable buffer depth audio HAL that never pulls at a rate 504 // < than overrunNs per buffer. 505 // - recovers from overrun immediately after underrun 506 // It doesn't work with a non-blocking audio HAL. 507 sleepNs = forceNs - nsec; 508 } else { 509 ignoreNextOverrun = false; 510 } 511 } 512#ifdef FAST_MIXER_STATISTICS 513 if (isWarm) { 514 // advance the FIFO queue bounds 515 size_t i = bounds & (FastMixerDumpState::kSamplingN - 1); 516 bounds = (bounds & 0xFFFF0000) | ((bounds + 1) & 0xFFFF); 517 if (full) { 518 bounds += 0x10000; 519 } else if (!(bounds & (FastMixerDumpState::kSamplingN - 1))) { 520 full = true; 521 } 522 // compute the delta value of clock_gettime(CLOCK_MONOTONIC) 523 uint32_t monotonicNs = nsec; 524 if (sec > 0 && sec < 4) { 525 monotonicNs += sec * 1000000000; 526 } 527 // compute the raw CPU load = delta value of clock_gettime(CLOCK_THREAD_CPUTIME_ID) 528 uint32_t loadNs = 0; 529 struct timespec newLoad; 530 rc = clock_gettime(CLOCK_THREAD_CPUTIME_ID, &newLoad); 531 if (rc == 0) { 532 if (oldLoadValid) { 533 sec = newLoad.tv_sec - oldLoad.tv_sec; 534 nsec = newLoad.tv_nsec - oldLoad.tv_nsec; 535 if (nsec < 0) { 536 --sec; 537 nsec += 1000000000; 538 } 539 loadNs = nsec; 540 if (sec > 0 && sec < 4) { 541 loadNs += sec * 1000000000; 542 } 543 } else { 544 // first time through the loop 545 oldLoadValid = true; 546 } 547 oldLoad = newLoad; 548 } 549#ifdef CPU_FREQUENCY_STATISTICS 550 // get the absolute value of CPU clock frequency in kHz 551 int cpuNum = sched_getcpu(); 552 uint32_t kHz = tcu.getCpukHz(cpuNum); 553 kHz = (kHz << 4) | (cpuNum & 0xF); 554#endif 555 // save values in FIFO queues for dumpsys 556 // these stores #1, #2, #3 are not atomic with respect to each other, 557 // or with respect to store #4 below 558 dumpState->mMonotonicNs[i] = monotonicNs; 559 dumpState->mLoadNs[i] = loadNs; 560#ifdef CPU_FREQUENCY_STATISTICS 561 dumpState->mCpukHz[i] = kHz; 562#endif 563 // this store #4 is not atomic with respect to stores #1, #2, #3 above, but 564 // the newest open and oldest closed halves are atomic with respect to each other 565 dumpState->mBounds = bounds; 566#if defined(ATRACE_TAG) && (ATRACE_TAG != ATRACE_TAG_NEVER) 567 ATRACE_INT("cycle_ms", monotonicNs / 1000000); 568 ATRACE_INT("load_us", loadNs / 1000); 569#endif 570 } 571#endif 572 } else { 573 // first time through the loop 574 oldTsValid = true; 575 sleepNs = periodNs; 576 ignoreNextOverrun = true; 577 } 578 oldTs = newTs; 579 } else { 580 // monotonic clock is broken 581 oldTsValid = false; 582 sleepNs = periodNs; 583 } 584 585 586 } // for (;;) 587 588 // never return 'true'; Thread::_threadLoop() locks mutex which can result in priority inversion 589} 590 591FastMixerDumpState::FastMixerDumpState() : 592 mCommand(FastMixerState::INITIAL), mWriteSequence(0), mFramesWritten(0), 593 mNumTracks(0), mWriteErrors(0), mUnderruns(0), mOverruns(0), 594 mSampleRate(0), mFrameCount(0), /* mMeasuredWarmupTs({0, 0}), */ mWarmupCycles(0), 595 mTrackMask(0) 596#ifdef FAST_MIXER_STATISTICS 597 , mBounds(0) 598#endif 599{ 600 mMeasuredWarmupTs.tv_sec = 0; 601 mMeasuredWarmupTs.tv_nsec = 0; 602 // sample arrays aren't accessed atomically with respect to the bounds, 603 // so clearing reduces chance for dumpsys to read random uninitialized samples 604 memset(&mMonotonicNs, 0, sizeof(mMonotonicNs)); 605 memset(&mLoadNs, 0, sizeof(mLoadNs)); 606#ifdef CPU_FREQUENCY_STATISTICS 607 memset(&mCpukHz, 0, sizeof(mCpukHz)); 608#endif 609} 610 611FastMixerDumpState::~FastMixerDumpState() 612{ 613} 614 615void FastMixerDumpState::dump(int fd) 616{ 617 if (mCommand == FastMixerState::INITIAL) { 618 fdprintf(fd, "FastMixer not initialized\n"); 619 return; 620 } 621#define COMMAND_MAX 32 622 char string[COMMAND_MAX]; 623 switch (mCommand) { 624 case FastMixerState::INITIAL: 625 strcpy(string, "INITIAL"); 626 break; 627 case FastMixerState::HOT_IDLE: 628 strcpy(string, "HOT_IDLE"); 629 break; 630 case FastMixerState::COLD_IDLE: 631 strcpy(string, "COLD_IDLE"); 632 break; 633 case FastMixerState::EXIT: 634 strcpy(string, "EXIT"); 635 break; 636 case FastMixerState::MIX: 637 strcpy(string, "MIX"); 638 break; 639 case FastMixerState::WRITE: 640 strcpy(string, "WRITE"); 641 break; 642 case FastMixerState::MIX_WRITE: 643 strcpy(string, "MIX_WRITE"); 644 break; 645 default: 646 snprintf(string, COMMAND_MAX, "%d", mCommand); 647 break; 648 } 649 double measuredWarmupMs = (mMeasuredWarmupTs.tv_sec * 1000.0) + 650 (mMeasuredWarmupTs.tv_nsec / 1000000.0); 651 double mixPeriodSec = (double) mFrameCount / (double) mSampleRate; 652 fdprintf(fd, "FastMixer command=%s writeSequence=%u framesWritten=%u\n" 653 " numTracks=%u writeErrors=%u underruns=%u overruns=%u\n" 654 " sampleRate=%u frameCount=%u measuredWarmup=%.3g ms, warmupCycles=%u\n" 655 " mixPeriod=%.2f ms\n", 656 string, mWriteSequence, mFramesWritten, 657 mNumTracks, mWriteErrors, mUnderruns, mOverruns, 658 mSampleRate, mFrameCount, measuredWarmupMs, mWarmupCycles, 659 mixPeriodSec * 1e3); 660#ifdef FAST_MIXER_STATISTICS 661 // find the interval of valid samples 662 uint32_t bounds = mBounds; 663 uint32_t newestOpen = bounds & 0xFFFF; 664 uint32_t oldestClosed = bounds >> 16; 665 uint32_t n = (newestOpen - oldestClosed) & 0xFFFF; 666 if (n > kSamplingN) { 667 ALOGE("too many samples %u", n); 668 n = kSamplingN; 669 } 670 // statistics for monotonic (wall clock) time, thread raw CPU load in time, CPU clock frequency, 671 // and adjusted CPU load in MHz normalized for CPU clock frequency 672 CentralTendencyStatistics wall, loadNs; 673#ifdef CPU_FREQUENCY_STATISTICS 674 CentralTendencyStatistics kHz, loadMHz; 675 uint32_t previousCpukHz = 0; 676#endif 677 // loop over all the samples 678 for (; n > 0; --n) { 679 size_t i = oldestClosed++ & (kSamplingN - 1); 680 uint32_t wallNs = mMonotonicNs[i]; 681 wall.sample(wallNs); 682 uint32_t sampleLoadNs = mLoadNs[i]; 683 loadNs.sample(sampleLoadNs); 684#ifdef CPU_FREQUENCY_STATISTICS 685 uint32_t sampleCpukHz = mCpukHz[i]; 686 // skip bad kHz samples 687 if ((sampleCpukHz & ~0xF) != 0) { 688 kHz.sample(sampleCpukHz >> 4); 689 if (sampleCpukHz == previousCpukHz) { 690 double megacycles = (double) sampleLoadNs * (double) (sampleCpukHz >> 4) * 1e-12; 691 double adjMHz = megacycles / mixPeriodSec; // _not_ wallNs * 1e9 692 loadMHz.sample(adjMHz); 693 } 694 } 695 previousCpukHz = sampleCpukHz; 696#endif 697 } 698 fdprintf(fd, "Simple moving statistics over last %.1f seconds:\n", wall.n() * mixPeriodSec); 699 fdprintf(fd, " wall clock time in ms per mix cycle:\n" 700 " mean=%.2f min=%.2f max=%.2f stddev=%.2f\n", 701 wall.mean()*1e-6, wall.minimum()*1e-6, wall.maximum()*1e-6, wall.stddev()*1e-6); 702 fdprintf(fd, " raw CPU load in us per mix cycle:\n" 703 " mean=%.0f min=%.0f max=%.0f stddev=%.0f\n", 704 loadNs.mean()*1e-3, loadNs.minimum()*1e-3, loadNs.maximum()*1e-3, 705 loadNs.stddev()*1e-3); 706#ifdef CPU_FREQUENCY_STATISTICS 707 fdprintf(fd, " CPU clock frequency in MHz:\n" 708 " mean=%.0f min=%.0f max=%.0f stddev=%.0f\n", 709 kHz.mean()*1e-3, kHz.minimum()*1e-3, kHz.maximum()*1e-3, kHz.stddev()*1e-3); 710 fdprintf(fd, " adjusted CPU load in MHz (i.e. normalized for CPU clock frequency):\n" 711 " mean=%.1f min=%.1f max=%.1f stddev=%.1f\n", 712 loadMHz.mean(), loadMHz.minimum(), loadMHz.maximum(), loadMHz.stddev()); 713#endif 714#endif 715 // The active track mask and track states are updated non-atomically. 716 // So if we relied on isActive to decide whether to display, 717 // then we might display an obsolete track or omit an active track. 718 // Instead we always display all tracks, with an indication 719 // of whether we think the track is active. 720 uint32_t trackMask = mTrackMask; 721 fdprintf(fd, "Fast tracks: kMaxFastTracks=%u activeMask=%#x\n", 722 FastMixerState::kMaxFastTracks, trackMask); 723 fdprintf(fd, "Index Active Full Partial Empty Recent Ready\n"); 724 for (uint32_t i = 0; i < FastMixerState::kMaxFastTracks; ++i, trackMask >>= 1) { 725 bool isActive = trackMask & 1; 726 const FastTrackDump *ftDump = &mTracks[i]; 727 const FastTrackUnderruns& underruns = ftDump->mUnderruns; 728 const char *mostRecent; 729 switch (underruns.mBitFields.mMostRecent) { 730 case UNDERRUN_FULL: 731 mostRecent = "full"; 732 break; 733 case UNDERRUN_PARTIAL: 734 mostRecent = "partial"; 735 break; 736 case UNDERRUN_EMPTY: 737 mostRecent = "empty"; 738 break; 739 default: 740 mostRecent = "?"; 741 break; 742 } 743 fdprintf(fd, "%5u %6s %4u %7u %5u %7s %5u\n", i, isActive ? "yes" : "no", 744 (underruns.mBitFields.mFull) & UNDERRUN_MASK, 745 (underruns.mBitFields.mPartial) & UNDERRUN_MASK, 746 (underruns.mBitFields.mEmpty) & UNDERRUN_MASK, 747 mostRecent, ftDump->mFramesReady); 748 } 749} 750 751} // namespace android 752