diff --git a/include/binder/Parcel.h b/include/binder/Parcel.h
index fd0fc1f..32c9a1d 100644
--- a/include/binder/Parcel.h
+++ b/include/binder/Parcel.h
@@ -26,11 +26,12 @@
 // ---------------------------------------------------------------------------
 namespace android {
 
+class Flattenable;
 class IBinder;
+class IPCThreadState;
 class ProcessState;
 class String8;
 class TextOutput;
-class Flattenable;
 
 struct flat_binder_object;  // defined in support_p/binder_module.h
 
@@ -61,10 +62,13 @@
 
     // Parses the RPC header, returning true if the interface name
     // in the header matches the expected interface from the caller.
-    // If strict_policy_out is non-NULL, the RPC header's StrictMode policy
-    // mask is returned.
+    //
+    // Additionally, enforceInterface does part of the work of
+    // propagating the StrictMode policy mask, populating the current
+    // IPCThreadState, which as an optimization may optionally be
+    // passed in.
     bool                enforceInterface(const String16& interface,
-                                         int32_t* strict_policy_out = NULL) const;
+                                         IPCThreadState* threadState = NULL) const;
     bool                checkInterface(IBinder*) const;
 
     void                freeData();
diff --git a/libs/binder/Parcel.cpp b/libs/binder/Parcel.cpp
index 60babad..18f75df 100644
--- a/libs/binder/Parcel.cpp
+++ b/libs/binder/Parcel.cpp
@@ -458,13 +458,13 @@
 }
 
 bool Parcel::enforceInterface(const String16& interface,
-                              int32_t* strict_policy_out) const
+                              IPCThreadState* threadState) const
 {
-    int32_t strict_policy = readInt32();
-    IPCThreadState::self()->setStrictModePolicy(strict_policy);
-    if (strict_policy_out != NULL) {
-      *strict_policy_out = strict_policy;
+    int32_t strictPolicy = readInt32();
+    if (threadState == NULL) {
+        threadState = IPCThreadState::self();
     }
+    threadState->setStrictModePolicy(strictPolicy);
     const String16 str(readString16());
     if (str == interface) {
         return true;