Merge changes I914fa057,I89ad4e2e am: b84297d910 am: 5de637151d am: 6004b4172d

Original change: https://android-review.googlesource.com/c/platform/frameworks/native/+/2147381

Change-Id: Id289c8c19a245e214339b90ca8abdefe054b14b4
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>
diff --git a/libs/binder/RpcState.cpp b/libs/binder/RpcState.cpp
index bde3d90..0ae75cd 100644
--- a/libs/binder/RpcState.cpp
+++ b/libs/binder/RpcState.cpp
@@ -736,7 +736,8 @@
     IPCThreadState* kernelBinderState = IPCThreadState::selfOrNull();
     IPCThreadState::SpGuard spGuard{
             .address = __builtin_frame_address(0),
-            .context = "processing binder RPC command",
+            .context = "processing binder RPC command (where RpcServer::setPerSessionRootObject is "
+                       "used to distinguish callers)",
     };
     const IPCThreadState::SpGuard* origGuard;
     if (kernelBinderState != nullptr) {
diff --git a/libs/binder/include/binder/IPCThreadState.h b/libs/binder/include/binder/IPCThreadState.h
index cd6a274..8ce3bc9 100644
--- a/libs/binder/include/binder/IPCThreadState.h
+++ b/libs/binder/include/binder/IPCThreadState.h
@@ -28,6 +28,10 @@
 // ---------------------------------------------------------------------------
 namespace android {
 
+/**
+ * Kernel binder thread state. All operations here refer to kernel binder. This
+ * object is allocated per-thread.
+ */
 class IPCThreadState
 {
 public:
diff --git a/libs/binder/include/binder/ProcessState.h b/libs/binder/include/binder/ProcessState.h
index e17a76c..882dfbf 100644
--- a/libs/binder/include/binder/ProcessState.h
+++ b/libs/binder/include/binder/ProcessState.h
@@ -29,6 +29,10 @@
 
 class IPCThreadState;
 
+/**
+ * Kernel binder process state. All operations here refer to kernel binder. This
+ * object is allocated per process.
+ */
 class ProcessState : public virtual RefBase {
 public:
     static sp<ProcessState> self();