commit 527bd1ec60a6aa0b4c263f767207b2dd9333a8d3
author Mingshu pang <quic_mpang@quicinc.com> Mon Sep 04 14:39:43 2023 +0800
committer BHARAT BOMMENA <quic_bbommena@quicinc.com> Tue Sep 19 00:21:10 2023 -0700
tree 02eab7122f1637981142f40c67de223b7d480b01
parent c44fe946bb5886fcbdd140b3239064aa0fd6bd7b

pal: Use increase/decrease StreamUserCounter to protect getTimestamp

1) Pcm Offload write takes 80ms and held agm session obj lock for 80ms,
   and if getTimestamp comes during this period, it is blocked by
   agm session obj lock.
2) getTimestamp for all streams is protected by resourceManager lock
   and active stream lock.
3) Active stream lock will block LL get timestamp and writing.
4) LL underrun happened.

Fix it by using increase/decrease StreamUserCounter to protect getTimestamp

Change-Id: Ib985fe26f5ec34b0e8a739bb3984d4f78e69128c
(cherry picked from commit 81a451c0462e6d5bf5966425bc7b89a029a58f0e)

Pal.cpp

diff --git a/Pal.cpp b/Pal.cpp
index 46b3b86..e0fc84f 100644
--- a/Pal.cpp
+++ b/Pal.cpp
@@ -892,13 +892,19 @@
     }
 
     rm->lockActiveStream();
-    if (rm->isActiveStream(stream_handle)) {
-        s =  reinterpret_cast<Stream *>(stream_handle);
-        status = s->getTimestamp(stime);
-    } else {
-        PAL_ERR(LOG_TAG, "stream handle in stale state.\n");
+    s =  reinterpret_cast<Stream *>(stream_handle);
+    status = rm->increaseStreamUserCounter(s);
+    if (0 != status) {
+        rm->unlockActiveStream();
+        PAL_ERR(LOG_TAG, "failed to increase stream user count");
+        return status;
     }
     rm->unlockActiveStream();
+    status = s->getTimestamp(stime);
+
+    rm->lockActiveStream();
+    rm->decreaseStreamUserCounter(s);
+    rm->unlockActiveStream();
 
     if (0 != status) {
         PAL_ERR(LOG_TAG, "pal_get_timestamp failed with status %d\n", status);