commit 42978e55fe438ecdc1b0bac5bf31c2aadbd9e78d
author Andreas Huber <andih@google.com> Thu Aug 27 10:08:39 2009 -0700
committer Andreas Huber <andih@google.com> Thu Aug 27 10:41:13 2009 -0700
tree 32c5794bd120a0367469b27d6387e13522648cde
parent 650b872c5aa54d94ef7a8e4a89daab11af15d5e0

An attempt to fix a deadlock between OMXCodec::start and upstream ::read

include/media/stagefright/OMXCodec.h

diff --git a/include/media/stagefright/OMXCodec.h b/include/media/stagefright/OMXCodec.h
index 08d550c..29cdf21 100644
--- a/include/media/stagefright/OMXCodec.h
+++ b/include/media/stagefright/OMXCodec.h
@@ -116,6 +116,7 @@
     State mState;
     Vector<BufferInfo> mPortBuffers[2];
     PortStatus mPortStatus[2];
+    bool mInitialBufferSubmit;
     bool mSignalledEOS;
     bool mNoMoreOutputData;
     int64_t mSeekTimeUs;

media/libstagefright/OMXCodec.cpp

diff --git a/media/libstagefright/OMXCodec.cpp b/media/libstagefright/OMXCodec.cpp
index 90ebd7e..38b5e5b 100644
--- a/media/libstagefright/OMXCodec.cpp
+++ b/media/libstagefright/OMXCodec.cpp
@@ -634,6 +634,7 @@
       mSource(source),
       mCodecSpecificDataIndex(0),
       mState(LOADED),
+      mInitialBufferSubmit(true),
       mSignalledEOS(false),
       mNoMoreOutputData(false),
       mSeekTimeUs(-1) {
@@ -666,7 +667,7 @@
 }
 
 status_t OMXCodec::init() {
-    Mutex::Autolock autoLock(mLock);
+    // mLock is held.
 
     CHECK_EQ(mState, LOADED);
 
@@ -1107,8 +1108,11 @@
 
             setState(EXECUTING);
 
-            drainInputBuffers();
-            fillOutputBuffers();
+            // Buffers will be submitted to the component in the first
+            // call to OMXCodec::read as mInitialBufferSubmit is true at
+            // this point. This ensures that this on_message call returns,
+            // releases the lock and ::init can notice the state change and
+            // itself return.
             break;
         }
 
@@ -1603,6 +1607,8 @@
 }
 
 status_t OMXCodec::start(MetaData *) {
+    Mutex::Autolock autoLock(mLock);
+
     if (mState != LOADED) {
         return UNKNOWN_ERROR;
     }
@@ -1618,6 +1624,7 @@
     }
 
     mCodecSpecificDataIndex = 0;
+    mInitialBufferSubmit = true;
     mSignalledEOS = false;
     mNoMoreOutputData = false;
     mSeekTimeUs = -1;
@@ -1699,6 +1706,13 @@
 
     Mutex::Autolock autoLock(mLock);
 
+    if (mInitialBufferSubmit) {
+        mInitialBufferSubmit = false;
+
+        drainInputBuffers();
+        fillOutputBuffers();
+    }
+
     if (mState != EXECUTING && mState != RECONFIGURING) {
         return UNKNOWN_ERROR;
     }