Fix sync fence FD leak in fenced compute.

Fixes: 192403402
Test: NNT_static
Test: Run TestGpuNnapi 100 times
Change-Id: I75ce4b32d6375cc9f6e87bb4dd2c4e78cbb1ea52

3 files changed, 2 insertions, 8 deletions

diff --git a/runtime/ExecutionBuilder.cpp b/runtime/ExecutionBuilder.cpp
index b2728a4fc..d9ccb0d30 100644
--- a/runtime/ExecutionBuilder.cpp
+++ b/runtime/ExecutionBuilder.cpp
@@ -996,9 +996,8 @@ int ExecutionBuilder::computeFenced(const std::vector<int>& waitFor,
     VLOG(EXECUTION) << "ExecutionBuilder::computeFenced";
     int result;
     const auto deadline = makeDeadline(mTimeoutDuration);
-    std::tie(result, mSyncFenceFd, mFencedExecutionCallback) =
+    std::tie(result, *syncFence, mFencedExecutionCallback) =
             computeFencedInternal(waitFor, timeoutDurationAfterFence, deadline);
-    *syncFence = mSyncFenceFd;
     // If there is an error, call finishComputation to mark the computation as completed.
     // Otherwise, we will call finishComputation in SyncFenceEvent::wait().
     if (result != ANEURALNETWORKS_NO_ERROR) {
diff --git a/runtime/ExecutionBuilder.h b/runtime/ExecutionBuilder.h
index a8709a748..4b3b1906f 100644
--- a/runtime/ExecutionBuilder.h
+++ b/runtime/ExecutionBuilder.h
@@ -166,8 +166,6 @@ class ExecutionBuilder {
 
     bool updateMemories();
 
-    bool hasSyncFence() const { return mSyncFenceFd > 0; }
-
     const ModelBuilder* mModel;
     const ExecutionPlan* mPlan;
 
@@ -243,10 +241,6 @@ class ExecutionBuilder {
     std::optional<bool> mOutputsFullySpecified;
     bool areOutputsFullySpecified();
 
-    // The sync fence fd that is created in the computeFenced call, if any.
-    // (Sometimes no sync fence fd will be created.)
-    int mSyncFenceFd = -1;
-
     // The callback used to query execution related info in the case of fenced
     // execution; otherwise, nullptr.  If the execution plan has multiple steps,
     // this is the callback associated with the last step.  If the last step
diff --git a/runtime/NeuralNetworks.cpp b/runtime/NeuralNetworks.cpp
index 053a8b780..b91d3ce45 100644
--- a/runtime/NeuralNetworks.cpp
+++ b/runtime/NeuralNetworks.cpp
@@ -1596,6 +1596,7 @@ int ANeuralNetworksExecution_startComputeWithDependencies(
             // TODO(miaowang): support dynamic output shape only with memory domain.
             // For now just return empty output shapes.
             [r](ErrorStatus status) { return r->finishComputation(status, {}); });
+    close(syncFenceToSignal);
     if (n != ANEURALNETWORKS_NO_ERROR) {
         *event = nullptr;
     } else {