Add comments
Change-Id: Ifbf3a46a4183c8abc0feee1c588953ab10303cc1
diff --git a/services/audioflinger/StateQueue.h b/services/audioflinger/StateQueue.h
index e33b3c6..9cde642 100644
--- a/services/audioflinger/StateQueue.h
+++ b/services/audioflinger/StateQueue.h
@@ -31,8 +31,14 @@
// and this may result in an audible artifact
// needs read-only access to a recent stable state,
// but not necessarily the most current one
+// only allocate and free memory when configuration changes
+// avoid conventional logging, as this is a form of I/O and could block
+// defer computation to other threads when feasible; for example
+// cycle times are collected by fast mixer thread but the floating-point
+// statistical calculations on these cycle times are computed by normal mixer
+// these requirements also apply to callouts such as AudioBufferProvider and VolumeProvider
// Normal mixer thread:
-// periodic with typical period ~40 ms
+// periodic with typical period ~20 ms
// SCHED_OTHER scheduling policy and nice priority == urgent audio
// ok to block, but prefer to avoid as much as possible
// needs read/write access to state
diff --git a/services/audioflinger/Threads.h b/services/audioflinger/Threads.h
index 7de6872..e15d98a 100644
--- a/services/audioflinger/Threads.h
+++ b/services/audioflinger/Threads.h
@@ -429,6 +429,8 @@
virtual status_t setSyncEvent(const sp<SyncEvent>& event);
virtual bool isValidSyncEvent(const sp<SyncEvent>& event) const;
+
+ // called with AudioFlinger lock held
void invalidateTracks(audio_stream_type_t streamType);