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authorThierry Bultel <thierry.bultel@iot.bzh>2018-06-26 17:28:23 +0200
committerThierry Bultel <thierry.bultel@iot.bzh>2018-06-26 17:28:23 +0200
commit731c21e80ba45339b7dd9b8eae63accd3597d281 (patch)
treeaa7d371fdf03eff93ade8f135b589edf53eef9ad /plugins/alsa/alsa-core-pcm.c
parent7a02db1106cc5fab6016b05a5c13d3dc7c6f0be9 (diff)
Rework the pcm copy loop and save a lot of CPUeel
- removed the systemd polling usage - uses a while loop for reading - improved the write loop, leveraging the available space at each iteration Signed-off-by: Thierry Bultel <thierry.bultel@iot.bzh>
Diffstat (limited to 'plugins/alsa/alsa-core-pcm.c')
-rw-r--r--plugins/alsa/alsa-core-pcm.c320
1 files changed, 180 insertions, 140 deletions
diff --git a/plugins/alsa/alsa-core-pcm.c b/plugins/alsa/alsa-core-pcm.c
index 7cec020..cc3d2f6 100644
--- a/plugins/alsa/alsa-core-pcm.c
+++ b/plugins/alsa/alsa-core-pcm.c
@@ -32,6 +32,12 @@ for the specific language governing permissions and
static int xrun(snd_pcm_t * pcm);
static int suspend(snd_pcm_t * pcm);
+static inline snd_pcm_uframes_t buf_avail(AlsaPcmCopyHandleT * chandle)
+{
+ return chandle->buf_size - chandle->buf_count;
+}
+
+
STATIC int AlsaPeriodSize(snd_pcm_format_t pcmFormat) {
int pcmSampleSize;
@@ -162,7 +168,9 @@ PUBLIC int AlsaPcmConf(SoftMixerT *mixer, AlsaPcmCtlT *pcm, AlsaPcmHwInfoT *opts
// store selected values
if ((error = snd_pcm_hw_params(pcm->handle, pxmHwParams)) < 0) {
- AFB_ApiError(mixer->api, "AlsaPcmConf: mixer=%s cardid=%s Fail apply hwparams error=%s", mixer->uid, pcm->cid.cardid, snd_strerror(error));
+ AFB_ApiError(mixer->api,
+ "%s: mixer=%s cardid=%s Fail apply hwparams error=%s",
+ __func__, mixer->uid, pcm->cid.cardid, snd_strerror(error));
goto OnErrorExit;
}
@@ -185,7 +193,7 @@ PUBLIC int AlsaPcmConf(SoftMixerT *mixer, AlsaPcmCtlT *pcm, AlsaPcmHwInfoT *opts
snd_pcm_sw_params_alloca(&pxmSwParams);
snd_pcm_sw_params_current(pcm->handle, pxmSwParams);
- if ((error = snd_pcm_sw_params_set_avail_min(pcm->handle, pxmSwParams, 1024)) < 0) {
+ if ((error = snd_pcm_sw_params_set_avail_min(pcm->handle, pxmSwParams, 6000)) < 0) {
AFB_ApiError(mixer->api,
"%s: mixer=%s cardid=%s Fail set_buffersize error=%s",
__func__, mixer->uid, pcm->cid.cardid, snd_strerror(error));
@@ -194,123 +202,168 @@ PUBLIC int AlsaPcmConf(SoftMixerT *mixer, AlsaPcmCtlT *pcm, AlsaPcmHwInfoT *opts
// push software params into PCM
if ((error = snd_pcm_sw_params(pcm->handle, pxmSwParams)) < 0) {
- AFB_ApiError(mixer->api, "AlsaPcmConf: mixer=%s cardid=%s Fail to push SW params error=%s", mixer->uid, pcm->cid.cardid, snd_strerror(error));
+ AFB_ApiError(mixer->api,
+ "%s: mixer=%s cardid=%s Fail to push SW params error=%s",
+ __func__, mixer->uid, pcm->cid.cardid, snd_strerror(error));
goto OnErrorExit;
};
- AFB_ApiNotice(mixer->api, "AlsaPcmConf: mixer=%s cardid=%s Done channels=%d rate=%d format=%d access=%d done", mixer->uid, pcm->cid.cardid, opts->channels, opts->rate, opts->format, opts->access);
+ AFB_ApiNotice(mixer->api,
+ "%s: mixer=%s cardid=%s Done channels=%d rate=%d format=%d access=%d done",
+ __func__, mixer->uid, pcm->cid.cardid, opts->channels, opts->rate, opts->format, opts->access);
return 0;
OnErrorExit:
return -1;
}
-STATIC int AlsaPcmReadCB(sd_event_source* src, int fd, uint32_t revents, void* userData) {
- char string[32];
-
- snd_pcm_sframes_t framesIn, framesOut, availIn, availOut, readIn;
- AlsaPcmCopyHandleT *pcmCopyHandle = (AlsaPcmCopyHandleT*) userData;
-
- // PCM has was closed
- if ((revents & EPOLLHUP) != 0) {
- AFB_ApiNotice(pcmCopyHandle->api,
- "%s PCM=%s hanghup/disconnected",
- __func__, ALSA_PCM_UID(pcmCopyHandle->pcmIn, string));
- goto ExitOnSuccess;
- }
-
- // ignore any non input events
- if ((revents & EPOLLIN) == 0) {
- goto ExitOnSuccess;
- }
-
- // do we have waiting frame
- availIn = snd_pcm_avail_update(pcmCopyHandle->pcmIn);
- if (availIn <= 0) {
- if (availIn == -EPIPE) {
- xrun(pcmCopyHandle->pcmIn);
- }
- goto ExitOnSuccess;
- }
-
- // do we have space to push frame
- availOut = snd_pcm_avail_update(pcmCopyHandle->pcmOut);
- if (availOut < 0) {
- if (availOut == -EPIPE) {
- xrun(pcmCopyHandle->pcmOut);
- goto ExitOnSuccess;
- }
- if (availOut == -ESTRPIPE) {
- suspend(pcmCopyHandle->pcmOut);
- goto ExitOnSuccess;
- }
- }
-
- if (availOut == 0)
- goto ExitOnSuccess;
+STATIC int AlsaPcmReadCB( struct pollfd * pfd, AlsaPcmCopyHandleT * pcmCopyHandle) {
+ char string[32];
- readIn = availIn;
+ snd_pcm_sframes_t availIn, availOut, availInBuf;
+ int err;
- // make sure we can push all input frame into output pcm without locking
- if (readIn > availOut)
- readIn = availOut;
+ // PCM has was closed
+ if ((pfd->revents & POLLHUP) != 0) {
+ AFB_ApiNotice(pcmCopyHandle->api,
+ "%s PCM=%s hanghup/disconnected",
+ __func__, ALSA_PCM_UID(pcmCopyHandle->pcmIn, string));
+ goto ExitOnSuccess;
+ }
- // we get too many data ignore some
- if (readIn > pcmCopyHandle->buf_size) {
- readIn = pcmCopyHandle->buf_size;
- }
+ // ignore any non input events
+ if ((pfd->revents & EPOLLIN) == 0) {
+ goto ExitOnSuccess;
+ }
- // effectively read pcmIn and push frame to pcmOut
- framesIn = snd_pcm_readi(pcmCopyHandle->pcmIn, pcmCopyHandle->buf, readIn);
- if (framesIn < 0 || framesIn != readIn) {
- AFB_ApiNotice(pcmCopyHandle->api,
- "%s PcmIn=%s READ UNDERUN framesIn=%ld, availIn %ld, max %ld, err %s",
- __func__, ALSA_PCM_UID(pcmCopyHandle->pcmIn, string), framesIn, readIn, pcmCopyHandle->buf_count, snd_strerror((int)framesIn));
- xrun(pcmCopyHandle->pcmIn);
- goto ExitOnSuccess;
- }
+ // do we have waiting frame
+ availIn = snd_pcm_avail_update(pcmCopyHandle->pcmIn);
+ if (availIn <= 0) {
+ if (availIn == -EPIPE) {
+ printf("XXX read EPIPE\n");
+ xrun(pcmCopyHandle->pcmIn);
+ }
+ goto ExitOnSuccess;
+ }
- unsigned long count = framesIn;
- char * data = pcmCopyHandle->buf;
+ availInBuf = buf_avail(pcmCopyHandle);
+
+ /* we get too much data, take what we can now,
+ * hopefully we will have more luck next time */
+
+ if (availIn > availInBuf)
+ availIn = availInBuf;
+
+ snd_pcm_sframes_t totalRead = 0;
+ snd_pcm_sframes_t totalWrite = 0;
+
+ while (availIn > 0) {
+ snd_pcm_sframes_t r = buf_avail(pcmCopyHandle);
+ if (r + pcmCopyHandle->buf_pos > pcmCopyHandle->buf_size)
+ r = pcmCopyHandle->buf_size - pcmCopyHandle->buf_pos;
+ if (r > availIn)
+ r = availIn;
+ r = snd_pcm_readi(pcmCopyHandle->pcmIn,
+ pcmCopyHandle->buf +
+ pcmCopyHandle->buf_pos *
+ pcmCopyHandle->frame_size, r);
+ if (r == 0)
+ goto ExitOnSuccess;
+ if (r < 0) {
+ if (r == -EPIPE) {
+ printf("read EPIPE (%d)\n", ++pcmCopyHandle->read_err_count);
+ err = xrun(pcmCopyHandle->pcmIn);
+ goto ExitOnSuccess;
+ } else if (r == -ESTRPIPE) {
+ printf("read ESTRPIPE\n");
+ if ((err = suspend(pcmCopyHandle->pcmIn)) < 0)
+ goto ExitOnSuccess;
+ r = 0;
+ } else {
+ goto ExitOnSuccess;;
+ }
+ }
+
+ totalRead += r;
+
+ pcmCopyHandle->buf_count += r;
+ pcmCopyHandle->buf_pos += r;
+ pcmCopyHandle->buf_pos %= pcmCopyHandle->buf_size;
+ availIn -= r;
+ }
- while (count > 0) {
- // In/Out frames transfer through buffer copy
+ // do we have space to push frame
+ availOut = snd_pcm_avail_update(pcmCopyHandle->pcmOut);
+ if (availOut < 0) {
+ if (availOut == -EPIPE) {
+ printf("write update EPIPE\n");
+ xrun(pcmCopyHandle->pcmOut);
+ goto ExitOnSuccess;
+ }
+ if (availOut == -ESTRPIPE) {
+ printf("write update ESTRPIPE\n");
+ suspend(pcmCopyHandle->pcmOut);
+ goto ExitOnSuccess;
+ }
+ }
- framesOut = snd_pcm_writei(pcmCopyHandle->pcmOut, data, count);
+ if (availOut == 0) {
+ printf("No space on playback\n");
+ goto ExitOnSuccess;
+ }
- if (framesOut == -EAGAIN) {
- printf("Write EAGAIN\n");
- snd_pcm_wait(pcmCopyHandle->pcmOut, 100);
- goto ExitOnSuccess;
- }
- if (framesOut == -EPIPE) {
- xrun(pcmCopyHandle->pcmOut);
- goto ExitOnSuccess;
- }
- if (framesOut == -ESTRPIPE) {
- suspend(pcmCopyHandle->pcmOut);
- goto ExitOnSuccess;
- }
- if (framesOut < 0 ) {
- printf("UNKNOWN ERROR\n");
- goto ExitOnSuccess;
- }
- count -= framesOut;
- data += framesOut * pcmCopyHandle->frame_size;
- }
+ while (pcmCopyHandle->buf_count > 0) {
+ // In/Out frames transfer through buffer copy
+ snd_pcm_sframes_t r = pcmCopyHandle->buf_count;
+
+ if (r + pcmCopyHandle->buf_pos > pcmCopyHandle->buf_size)
+ r = pcmCopyHandle->buf_size - pcmCopyHandle->buf_pos;
+ if (r > availOut)
+ r = availOut;
+
+ r = snd_pcm_writei(
+ pcmCopyHandle->pcmOut,
+ pcmCopyHandle->buf +
+ pcmCopyHandle->buf_pos *
+ pcmCopyHandle->frame_size, r);
+ if (r <= 0) {
+ if (r == -EPIPE) {
+ printf("XXX write EPIPE (%d)\n", ++pcmCopyHandle->write_err_count );
+ err = xrun(pcmCopyHandle->pcmOut);
+ continue;
+ } else if (r == -ESTRPIPE) {
+ printf("XXX write ESTRPIPE\n");
+ goto ExitOnSuccess;
+ }
+ printf("Unhandled error %s\n", strerror(errno));
+ goto ExitOnSuccess;
+ }
+
+ totalWrite += r;
+
+ pcmCopyHandle->buf_count -= r;
+ pcmCopyHandle->buf_pos += r;
+ pcmCopyHandle->buf_pos %= pcmCopyHandle->buf_size;
+
+ /* We evaluate the available space on device again,
+ * because it may have grown since the measured the value
+ * before the loop. If we ignore a new bigger value, we will keep
+ * writing small chunks, keep in tight loops and stave the CPU */
+
+ snd_pcm_sframes_t newAvailOut = snd_pcm_avail(pcmCopyHandle->pcmOut);
+
+ if (newAvailOut == 0) {
+ snd_pcm_wait(pcmCopyHandle->pcmOut, 5);
+ } else if (newAvailOut > 0) {
+ availOut = newAvailOut;
+ }
+ }
- if (framesIn != framesOut) {
- AFB_ApiNotice(pcmCopyHandle->api,
- "%s PCM=%s Loosing frames=%ld",
- __func__, ALSA_PCM_UID(pcmCopyHandle->pcmOut, string), (framesIn - framesOut));
- goto ExitOnSuccess;
- }
-
- return 0;
+ return 0;
- // Cannot handle error in callback
+ // Cannot handle error in callback
ExitOnSuccess:
- return 0;
+ return 0;
}
@@ -318,10 +371,7 @@ static int xrun( snd_pcm_t * pcm)
{
int err;
- printf("xrun !\n");
-
if ((err = snd_pcm_prepare(pcm)) < 0) {
- printf("xrun: prepare failed\n");
return err;
}
@@ -332,10 +382,7 @@ static int suspend( snd_pcm_t * pcm)
{
int err;
- printf("suspend !\n");
-
while ((err = snd_pcm_resume(pcm)) == -EAGAIN) {
- printf("%s: again\n", __func__);
usleep(1);
}
if (err < 0)
@@ -346,31 +393,35 @@ static int suspend( snd_pcm_t * pcm)
static void *LoopInThread(void *handle) {
AlsaPcmCopyHandleT *pcmCopyHandle = (AlsaPcmCopyHandleT*) handle;
- int count = 0;
- int watchdog = MAINLOOP_WATCHDOG * 1000;
pcmCopyHandle->tid = (int) syscall(SYS_gettid);
AFB_ApiNotice(pcmCopyHandle->api,
"%s :%s/%d Started",
__func__, pcmCopyHandle->info, pcmCopyHandle->tid);
+ for (int ix=0; ix<pcmCopyHandle->pcmInCount; ix++) {
+ struct pollfd * pfd = &pcmCopyHandle->pollFds[ix];
+ pfd->events = POLLIN | POLLHUP;
+ }
+
/* loop until end */
for (;;) {
- int res = sd_event_run(pcmCopyHandle->sdLoop, watchdog);
- if (res == 0) {
- AFB_ApiInfo(pcmCopyHandle->api,
- "%s:%s/%d Idle count=%d",
- __func__, pcmCopyHandle->info, pcmCopyHandle->tid, count++);
- continue;
- }
- if (res < 0) {
- AFB_ApiError(pcmCopyHandle->api,
- "%s:%s/%d ERROR=%i Exit errno=%s.\n",
- __func__, pcmCopyHandle->info, pcmCopyHandle->tid, res, strerror(res));
- break;
- }
- }
- pthread_exit(0);
+
+ int err = poll(pcmCopyHandle->pollFds, pcmCopyHandle->pcmInCount, 5000); // TODO
+
+ if (err < 0)
+ continue;
+
+ if (err == 0) {
+ /* timeout */
+ continue;
+ }
+
+ for (int ix=0;ix<pcmCopyHandle->pcmInCount; ix++)
+ AlsaPcmReadCB(&pcmCopyHandle->pollFds[ix], pcmCopyHandle);
+ }
+
+ pthread_exit(0);
}
static inline snd_pcm_uframes_t time_to_frames(unsigned int rate,
@@ -450,7 +501,10 @@ PUBLIC int AlsaPcmCopy(SoftMixerT *mixer, AlsaStreamAudioT *stream, AlsaPcmCtlT
size_t size = cHandle->latency * 2;
cHandle->buf = calloc(1, size*cHandle->frame_size);
cHandle->buf_count = 0;
- cHandle->buf_size = size;
+ cHandle->buf_pos = 0;
+ cHandle->buf_size = size;
+ cHandle->read_err_count = 0;
+ cHandle->write_err_count = 0;
AFB_ApiInfo(mixer->api, "%s Copy buf size is %zu", __func__, size);
@@ -463,7 +517,7 @@ PUBLIC int AlsaPcmCopy(SoftMixerT *mixer, AlsaStreamAudioT *stream, AlsaPcmCtlT
goto OnErrorExit;
};
- pcmInFds = alloca(sizeof (*pcmInFds) * pcmInCount);
+ pcmInFds = malloc(sizeof (*pcmInFds) * pcmInCount);
if ((error = snd_pcm_poll_descriptors(pcmIn->handle, pcmInFds, pcmInCount)) < 0) {
AFB_ApiError(mixer->api,
"%s: Fail pcmIn=%s get pollfds error=%s",
@@ -471,22 +525,8 @@ PUBLIC int AlsaPcmCopy(SoftMixerT *mixer, AlsaStreamAudioT *stream, AlsaPcmCtlT
goto OnErrorExit;
};
- // add poll descriptor to AGL systemd mainloop
- if ((error = sd_event_new(&cHandle->sdLoop)) < 0) {
- AFB_ApiError(mixer->api,
- "%s: fail pcmin=%s creating a new loop: %s\n",
- __func__, ALSA_PCM_UID(pcmOut->handle, string), strerror(error));
- goto OnErrorExit;
- }
-
- for (int idx = 0; idx < pcmInCount; idx++) {
- if ((error = sd_event_add_io(cHandle->sdLoop, &cHandle->evtsrc, pcmInFds[idx].fd, EPOLLIN, AlsaPcmReadCB, cHandle)) < 0) {
- AFB_ApiError(mixer->api,
- "%s: Fail pcmIn=%s sd_event_add_io err=%d",
- __func__, ALSA_PCM_UID(pcmIn->handle, string), error);
- goto OnErrorExit;
- }
- }
+ cHandle->pollFds = pcmInFds;
+ cHandle->pcmInCount = pcmInCount;
// start a thread with a mainloop to monitor Audio-Agent
if ((error = pthread_create(&cHandle->thread, NULL, &LoopInThread, cHandle)) < 0) {