commit 56ce2edb667408420032e4c6535b0128f4484b10
author Andy Hung <hunga@google.com> Wed Jun 12 16:03:16 2024 -0700
committer Andy Hung <hunga@google.com> Fri Jun 14 18:24:22 2024 -0700
tree 760a65ea56084a19566960d93ec27dfbce521003
parent 2718e0195adc0de3cf674a1ea98eda5e9c32e1fc

AudioFlinger: defer restartIfDisabled()

Defer restartIfDisabled() to the end of
the threadLoop worker thread, allowing execution
without any mutexes held. This prevents mutex
order issues.

To accomplish this, we add a DeferredExecutor object
to ThreadBase, which allows adding functors and dtors
to execute at the end of the worker loop,
where no mutexes are held.

Test: atest AudioPlaybackCaptureTest
Bug: 345400492
Bug: 345676143
Change-Id: I1d7f491fc1289882ce67cb7289b3bc1b58e81d23

services/audioflinger/Threads.cpp

diff --git a/services/audioflinger/Threads.cpp b/services/audioflinger/Threads.cpp
index 2b17e92..98faf38 100644
--- a/services/audioflinger/Threads.cpp
+++ b/services/audioflinger/Threads.cpp
@@ -4582,7 +4582,11 @@
 
         // FIXME Note that the above .clear() is no longer necessary since effectChains
         // is now local to this block, but will keep it for now (at least until merge done).
+
+        mThreadloopExecutor.process();
     }
+    mThreadloopExecutor.process(); // process any remaining deferred actions.
+    // deferred actions after this point are ignored.
 
     threadLoop_exit();
 
@@ -8732,11 +8736,14 @@
             mIoJitterMs.add(jitterMs);
             mProcessTimeMs.add(processMs);
         }
+       mThreadloopExecutor.process();
         // update timing info.
         mLastIoBeginNs = lastIoBeginNs;
         mLastIoEndNs = lastIoEndNs;
         lastLoopCountRead = loopCount;
     }
+    mThreadloopExecutor.process(); // process any remaining deferred actions.
+    // deferred actions after this point are ignored.
 
     standbyIfNotAlreadyInStandby();
 
@@ -10522,7 +10529,10 @@
         unlockEffectChains(effectChains);
         // Effect chains will be actually deleted here if they were removed from
         // mEffectChains list during mixing or effects processing
+        mThreadloopExecutor.process();
     }
+    mThreadloopExecutor.process(); // process any remaining deferred actions.
+    // deferred actions after this point are ignored.
 
     threadLoop_exit();