diff options
Diffstat (limited to 'services/audioflinger/FastMixer.cpp')
| -rw-r--r-- | services/audioflinger/FastMixer.cpp | 53 |
1 files changed, 32 insertions, 21 deletions
diff --git a/services/audioflinger/FastMixer.cpp b/services/audioflinger/FastMixer.cpp index 3c8a256..21df1d7 100644 --- a/services/audioflinger/FastMixer.cpp +++ b/services/audioflinger/FastMixer.cpp @@ -14,9 +14,17 @@ * limitations under the License. */ +// <IMPORTANT_WARNING> +// Design rules for threadLoop() are given in the comments at section "Fast mixer thread" of +// StateQueue.h. In particular, avoid library and system calls except at well-known points. +// The design rules are only for threadLoop(), and don't apply to FastMixerDumpState methods. +// </IMPORTANT_WARNING> + #define LOG_TAG "FastMixer" //#define LOG_NDEBUG 0 +#define ATRACE_TAG ATRACE_TAG_AUDIO + #include <sys/atomics.h> #include <time.h> #include <utils/Log.h> @@ -84,6 +92,7 @@ bool FastMixer::threadLoop() struct timespec measuredWarmupTs = {0, 0}; // how long did it take for warmup to complete uint32_t warmupCycles = 0; // counter of number of loop cycles required to warmup NBAIO_Sink* teeSink = NULL; // if non-NULL, then duplicate write() to this non-blocking sink + NBLog::Writer dummyLogWriter, *logWriter = &dummyLogWriter; for (;;) { @@ -114,6 +123,10 @@ bool FastMixer::threadLoop() // As soon as possible of learning of a new dump area, start using it dumpState = next->mDumpState != NULL ? next->mDumpState : &dummyDumpState; teeSink = next->mTeeSink; + logWriter = next->mNBLogWriter != NULL ? next->mNBLogWriter : &dummyLogWriter; + if (mixer != NULL) { + mixer->setLog(logWriter); + } // We want to always have a valid reference to the previous (non-idle) state. // However, the state queue only guarantees access to current and previous states. @@ -157,6 +170,10 @@ bool FastMixer::threadLoop() if (old <= 0) { __futex_syscall4(coldFutexAddr, FUTEX_WAIT_PRIVATE, old - 1, NULL); } + int policy = sched_getscheduler(0); + if (!(policy == SCHED_FIFO || policy == SCHED_RR)) { + ALOGE("did not receive expected priority boost"); + } // This may be overly conservative; there could be times that the normal mixer // requests such a brief cold idle that it doesn't require resetting this flag. isWarm = false; @@ -301,7 +318,7 @@ bool FastMixer::threadLoop() generations[i] = fastTrack->mGeneration; } - // finally process modified tracks; these use the same slot + // finally process (potentially) modified tracks; these use the same slot // but may have a different buffer provider or volume provider unsigned modifiedTracks = currentTrackMask & previousTrackMask; while (modifiedTracks != 0) { @@ -309,6 +326,7 @@ bool FastMixer::threadLoop() modifiedTracks &= ~(1 << i); const FastTrack* fastTrack = ¤t->mFastTracks[i]; if (fastTrack->mGeneration != generations[i]) { + // this track was actually modified AudioBufferProvider *bufferProvider = fastTrack->mBufferProvider; ALOG_ASSERT(bufferProvider != NULL); if (mixer != NULL) { @@ -371,14 +389,14 @@ bool FastMixer::threadLoop() // up to 1 ms. If enough active tracks all blocked in sequence, this would result // in the overall fast mix cycle being delayed. Should use a non-blocking FIFO. size_t framesReady = fastTrack->mBufferProvider->framesReady(); -#if defined(ATRACE_TAG) && (ATRACE_TAG != ATRACE_TAG_NEVER) - // I wish we had formatted trace names - char traceName[16]; - strcpy(traceName, "framesReady"); - traceName[11] = i + (i < 10 ? '0' : 'A' - 10); - traceName[12] = '\0'; - ATRACE_INT(traceName, framesReady); -#endif + if (ATRACE_ENABLED()) { + // I wish we had formatted trace names + char traceName[16]; + strcpy(traceName, "fRdy"); + traceName[4] = i + (i < 10 ? '0' : 'A' - 10); + traceName[5] = '\0'; + ATRACE_INT(traceName, framesReady); + } FastTrackDump *ftDump = &dumpState->mTracks[i]; FastTrackUnderruns underruns = ftDump->mUnderruns; if (framesReady < frameCount) { @@ -424,16 +442,12 @@ bool FastMixer::threadLoop() // FIXME write() is non-blocking and lock-free for a properly implemented NBAIO sink, // but this code should be modified to handle both non-blocking and blocking sinks dumpState->mWriteSequence++; -#if defined(ATRACE_TAG) && (ATRACE_TAG != ATRACE_TAG_NEVER) - Tracer::traceBegin(ATRACE_TAG, "write"); -#endif + ATRACE_BEGIN("write"); ssize_t framesWritten = outputSink->write(mixBuffer, frameCount); -#if defined(ATRACE_TAG) && (ATRACE_TAG != ATRACE_TAG_NEVER) - Tracer::traceEnd(ATRACE_TAG); -#endif + ATRACE_END(); dumpState->mWriteSequence++; if (framesWritten >= 0) { - ALOG_ASSERT(framesWritten <= frameCount); + ALOG_ASSERT((size_t) framesWritten <= frameCount); dumpState->mFramesWritten += framesWritten; //if ((size_t) framesWritten == frameCount) { // didFullWrite = true; @@ -451,6 +465,7 @@ bool FastMixer::threadLoop() struct timespec newTs; int rc = clock_gettime(CLOCK_MONOTONIC, &newTs); if (rc == 0) { + //logWriter->logTimestamp(newTs); if (oldTsValid) { time_t sec = newTs.tv_sec - oldTs.tv_sec; long nsec = newTs.tv_nsec - oldTs.tv_nsec; @@ -485,9 +500,7 @@ bool FastMixer::threadLoop() sleepNs = -1; if (isWarm) { if (sec > 0 || nsec > underrunNs) { -#if defined(ATRACE_TAG) && (ATRACE_TAG != ATRACE_TAG_NEVER) - ScopedTrace st(ATRACE_TAG, "underrun"); -#endif + ATRACE_NAME("underrun"); // FIXME only log occasionally ALOGV("underrun: time since last cycle %d.%03ld sec", (int) sec, nsec / 1000000L); @@ -567,10 +580,8 @@ bool FastMixer::threadLoop() // this store #4 is not atomic with respect to stores #1, #2, #3 above, but // the newest open and oldest closed halves are atomic with respect to each other dumpState->mBounds = bounds; -#if defined(ATRACE_TAG) && (ATRACE_TAG != ATRACE_TAG_NEVER) ATRACE_INT("cycle_ms", monotonicNs / 1000000); ATRACE_INT("load_us", loadNs / 1000); -#endif } #endif } else { |