diff --git a/drivers/acpi/acpica/acobject.h b/drivers/acpi/acpica/acobject.h
index bdbfaf22bd14..efaf9c6090f5 100644
--- a/drivers/acpi/acpica/acobject.h
+++ b/drivers/acpi/acpica/acobject.h
@@ -97,8 +97,6 @@
 #define AOPOBJ_OBJECT_INITIALIZED   0x08	/* Region is initialized, _REG was run */
 #define AOPOBJ_SETUP_COMPLETE       0x10	/* Region setup is complete */
 #define AOPOBJ_INVALID              0x20	/* Host OS won't allow a Region address */
-#define AOPOBJ_MODULE_LEVEL         0x40	/* Method is actually module-level code */
-#define AOPOBJ_MODIFIED_NAMESPACE   0x80	/* Method modified the namespace */
 
 /******************************************************************************
  *
@@ -175,7 +173,7 @@ struct acpi_object_region {
 };
 
 struct acpi_object_method {
-	ACPI_OBJECT_COMMON_HEADER u8 method_flags;
+	ACPI_OBJECT_COMMON_HEADER u8 info_flags;
 	u8 param_count;
 	u8 sync_level;
 	union acpi_operand_object *mutex;
@@ -183,13 +181,21 @@ struct acpi_object_method {
 	union {
 		ACPI_INTERNAL_METHOD implementation;
 		union acpi_operand_object *handler;
-	} extra;
+	} dispatch;
 
 	u32 aml_length;
 	u8 thread_count;
 	acpi_owner_id owner_id;
 };
 
+/* Flags for info_flags field above */
+
+#define ACPI_METHOD_MODULE_LEVEL        0x01	/* Method is actually module-level code */
+#define ACPI_METHOD_INTERNAL_ONLY       0x02	/* Method is implemented internally (_OSI) */
+#define ACPI_METHOD_SERIALIZED          0x04	/* Method is serialized */
+#define ACPI_METHOD_SERIALIZED_PENDING  0x08	/* Method is to be marked serialized */
+#define ACPI_METHOD_MODIFIED_NAMESPACE  0x10	/* Method modified the namespace */
+
 /******************************************************************************
  *
  * Objects that can be notified.  All share a common notify_info area.
diff --git a/drivers/acpi/acpica/amlcode.h b/drivers/acpi/acpica/amlcode.h
index 1f484ba228fc..ac1f561ce392 100644
--- a/drivers/acpi/acpica/amlcode.h
+++ b/drivers/acpi/acpica/amlcode.h
@@ -480,16 +480,10 @@ typedef enum {
 	AML_FIELD_ATTRIB_SMB_BLOCK_CALL = 0x0D
 } AML_ACCESS_ATTRIBUTE;
 
-/* Bit fields in method_flags byte */
+/* Bit fields in the AML method_flags byte */
 
 #define AML_METHOD_ARG_COUNT        0x07
 #define AML_METHOD_SERIALIZED       0x08
 #define AML_METHOD_SYNC_LEVEL       0xF0
 
-/* METHOD_FLAGS_ARG_COUNT is not used internally, define additional flags */
-
-#define AML_METHOD_INTERNAL_ONLY    0x01
-#define AML_METHOD_RESERVED1        0x02
-#define AML_METHOD_RESERVED2        0x04
-
 #endif				/* __AMLCODE_H__ */
diff --git a/drivers/acpi/acpica/dsmethod.c b/drivers/acpi/acpica/dsmethod.c
index d94dd8974b55..5a79f401a113 100644
--- a/drivers/acpi/acpica/dsmethod.c
+++ b/drivers/acpi/acpica/dsmethod.c
@@ -43,7 +43,6 @@
 
 #include <acpi/acpi.h>
 #include "accommon.h"
-#include "amlcode.h"
 #include "acdispat.h"
 #include "acinterp.h"
 #include "acnamesp.h"
@@ -201,7 +200,7 @@ acpi_ds_begin_method_execution(struct acpi_namespace_node *method_node,
 	/*
 	 * If this method is serialized, we need to acquire the method mutex.
 	 */
-	if (obj_desc->method.method_flags & AML_METHOD_SERIALIZED) {
+	if (obj_desc->method.info_flags & ACPI_METHOD_SERIALIZED) {
 		/*
 		 * Create a mutex for the method if it is defined to be Serialized
 		 * and a mutex has not already been created. We defer the mutex creation
@@ -413,8 +412,9 @@ acpi_ds_call_control_method(struct acpi_thread_state *thread,
 
 	/* Invoke an internal method if necessary */
 
-	if (obj_desc->method.method_flags & AML_METHOD_INTERNAL_ONLY) {
-		status = obj_desc->method.extra.implementation(next_walk_state);
+	if (obj_desc->method.info_flags & ACPI_METHOD_INTERNAL_ONLY) {
+		status =
+		    obj_desc->method.dispatch.implementation(next_walk_state);
 		if (status == AE_OK) {
 			status = AE_CTRL_TERMINATE;
 		}
@@ -579,11 +579,14 @@ acpi_ds_terminate_control_method(union acpi_operand_object *method_desc,
 
 		/*
 		 * Delete any namespace objects created anywhere within the
-		 * namespace by the execution of this method. Unless this method
-		 * is a module-level executable code method, in which case we
-		 * want make the objects permanent.
+		 * namespace by the execution of this method. Unless:
+		 * 1) This method is a module-level executable code method, in which
+		 *    case we want make the objects permanent.
+		 * 2) There are other threads executing the method, in which case we
+		 *    will wait until the last thread has completed.
 		 */
-		if (!(method_desc->method.flags & AOPOBJ_MODULE_LEVEL)) {
+		if (!(method_desc->method.info_flags & ACPI_METHOD_MODULE_LEVEL)
+		    && (method_desc->method.thread_count == 1)) {
 
 			/* Delete any direct children of (created by) this method */
 
@@ -593,12 +596,17 @@ acpi_ds_terminate_control_method(union acpi_operand_object *method_desc,
 			/*
 			 * Delete any objects that were created by this method
 			 * elsewhere in the namespace (if any were created).
+			 * Use of the ACPI_METHOD_MODIFIED_NAMESPACE optimizes the
+			 * deletion such that we don't have to perform an entire
+			 * namespace walk for every control method execution.
 			 */
 			if (method_desc->method.
-			    flags & AOPOBJ_MODIFIED_NAMESPACE) {
+			    info_flags & ACPI_METHOD_MODIFIED_NAMESPACE) {
 				acpi_ns_delete_namespace_by_owner(method_desc->
 								  method.
 								  owner_id);
+				method_desc->method.info_flags &=
+				    ~ACPI_METHOD_MODIFIED_NAMESPACE;
 			}
 		}
 	}
@@ -629,19 +637,43 @@ acpi_ds_terminate_control_method(union acpi_operand_object *method_desc,
 		 * Serialized if it appears that the method is incorrectly written and
 		 * does not support multiple thread execution. The best example of this
 		 * is if such a method creates namespace objects and blocks. A second
-		 * thread will fail with an AE_ALREADY_EXISTS exception
+		 * thread will fail with an AE_ALREADY_EXISTS exception.
 		 *
 		 * This code is here because we must wait until the last thread exits
-		 * before creating the synchronization semaphore.
+		 * before marking the method as serialized.
 		 */
-		if ((method_desc->method.method_flags & AML_METHOD_SERIALIZED)
-		    && (!method_desc->method.mutex)) {
-			(void)acpi_ds_create_method_mutex(method_desc);
+		if (method_desc->method.
+		    info_flags & ACPI_METHOD_SERIALIZED_PENDING) {
+			if (walk_state) {
+				ACPI_INFO((AE_INFO,
+					   "Marking method %4.4s as Serialized because of AE_ALREADY_EXISTS error",
+					   walk_state->method_node->name.
+					   ascii));
+			}
+
+			/*
+			 * Method tried to create an object twice and was marked as
+			 * "pending serialized". The probable cause is that the method
+			 * cannot handle reentrancy.
+			 *
+			 * The method was created as not_serialized, but it tried to create
+			 * a named object and then blocked, causing the second thread
+			 * entrance to begin and then fail. Workaround this problem by
+			 * marking the method permanently as Serialized when the last
+			 * thread exits here.
+			 */
+			method_desc->method.info_flags &=
+			    ~ACPI_METHOD_SERIALIZED_PENDING;
+			method_desc->method.info_flags |=
+			    ACPI_METHOD_SERIALIZED;
+			method_desc->method.sync_level = 0;
 		}
 
 		/* No more threads, we can free the owner_id */
 
-		if (!(method_desc->method.flags & AOPOBJ_MODULE_LEVEL)) {
+		if (!
+		    (method_desc->method.
+		     info_flags & ACPI_METHOD_MODULE_LEVEL)) {
 			acpi_ut_release_owner_id(&method_desc->method.owner_id);
 		}
 	}
diff --git a/drivers/acpi/acpica/evrgnini.c b/drivers/acpi/acpica/evrgnini.c
index 0b47a6dc9290..2ef32e952559 100644
--- a/drivers/acpi/acpica/evrgnini.c
+++ b/drivers/acpi/acpica/evrgnini.c
@@ -590,9 +590,9 @@ acpi_ev_initialize_region(union acpi_operand_object *region_obj,
 				 * See acpi_ns_exec_module_code
 				 */
 				if (obj_desc->method.
-				    flags & AOPOBJ_MODULE_LEVEL) {
+				    info_flags & ACPI_METHOD_MODULE_LEVEL) {
 					handler_obj =
-					    obj_desc->method.extra.handler;
+					    obj_desc->method.dispatch.handler;
 				}
 				break;
 
diff --git a/drivers/acpi/acpica/excreate.c b/drivers/acpi/acpica/excreate.c
index 3c61b48c73f5..ffac8c7e54c5 100644
--- a/drivers/acpi/acpica/excreate.c
+++ b/drivers/acpi/acpica/excreate.c
@@ -482,13 +482,11 @@ acpi_ex_create_method(u8 * aml_start,
 	obj_desc->method.aml_length = aml_length;
 
 	/*
-	 * Disassemble the method flags. Split off the Arg Count
-	 * for efficiency
+	 * Disassemble the method flags. Split off the arg_count, Serialized
+	 * flag, and sync_level for efficiency.
 	 */
 	method_flags = (u8) operand[1]->integer.value;
 
-	obj_desc->method.method_flags =
-	    (u8) (method_flags & ~AML_METHOD_ARG_COUNT);
 	obj_desc->method.param_count =
 	    (u8) (method_flags & AML_METHOD_ARG_COUNT);
 
@@ -497,6 +495,8 @@ acpi_ex_create_method(u8 * aml_start,
 	 * created for this method when it is parsed.
 	 */
 	if (method_flags & AML_METHOD_SERIALIZED) {
+		obj_desc->method.info_flags = ACPI_METHOD_SERIALIZED;
+
 		/*
 		 * ACPI 1.0: sync_level = 0
 		 * ACPI 2.0: sync_level = sync_level in method declaration
diff --git a/drivers/acpi/acpica/exdump.c b/drivers/acpi/acpica/exdump.c
index f067bbb0d961..ff4b1e61c318 100644
--- a/drivers/acpi/acpica/exdump.c
+++ b/drivers/acpi/acpica/exdump.c
@@ -122,7 +122,7 @@ static struct acpi_exdump_info acpi_ex_dump_event[2] = {
 
 static struct acpi_exdump_info acpi_ex_dump_method[9] = {
 	{ACPI_EXD_INIT, ACPI_EXD_TABLE_SIZE(acpi_ex_dump_method), NULL},
-	{ACPI_EXD_UINT8, ACPI_EXD_OFFSET(method.method_flags), "Method Flags"},
+	{ACPI_EXD_UINT8, ACPI_EXD_OFFSET(method.info_flags), "Info Flags"},
 	{ACPI_EXD_UINT8, ACPI_EXD_OFFSET(method.param_count),
 	 "Parameter Count"},
 	{ACPI_EXD_UINT8, ACPI_EXD_OFFSET(method.sync_level), "Sync Level"},
diff --git a/drivers/acpi/acpica/nsaccess.c b/drivers/acpi/acpica/nsaccess.c
index 0cd925be5fc1..cede0e3200e4 100644
--- a/drivers/acpi/acpica/nsaccess.c
+++ b/drivers/acpi/acpica/nsaccess.c
@@ -163,9 +163,9 @@ acpi_status acpi_ns_root_initialize(void)
 #else
 				/* Mark this as a very SPECIAL method */
 
-				obj_desc->method.method_flags =
-				    AML_METHOD_INTERNAL_ONLY;
-				obj_desc->method.extra.implementation =
+				obj_desc->method.info_flags =
+				    ACPI_METHOD_INTERNAL_ONLY;
+				obj_desc->method.dispatch.implementation =
 				    acpi_ut_osi_implementation;
 #endif
 				break;
diff --git a/drivers/acpi/acpica/nsalloc.c b/drivers/acpi/acpica/nsalloc.c
index 222a23e838d6..222a9843268d 100644
--- a/drivers/acpi/acpica/nsalloc.c
+++ b/drivers/acpi/acpica/nsalloc.c
@@ -234,8 +234,8 @@ void acpi_ns_install_node(struct acpi_walk_state *walk_state, struct acpi_namesp
 			 * modified the namespace. This is used for cleanup when the
 			 * method exits.
 			 */
-			walk_state->method_desc->method.flags |=
-			    AOPOBJ_MODIFIED_NAMESPACE;
+			walk_state->method_desc->method.info_flags |=
+			    ACPI_METHOD_MODIFIED_NAMESPACE;
 		}
 	}
 
diff --git a/drivers/acpi/acpica/nseval.c b/drivers/acpi/acpica/nseval.c
index f52829cc294b..a55c0d2295ca 100644
--- a/drivers/acpi/acpica/nseval.c
+++ b/drivers/acpi/acpica/nseval.c
@@ -389,7 +389,7 @@ acpi_ns_exec_module_code(union acpi_operand_object *method_obj,
 	 * acpi_gbl_root_node->Object is NULL at PASS1.
 	 */
 	if ((type == ACPI_TYPE_DEVICE) && parent_node->object) {
-		method_obj->method.extra.handler =
+		method_obj->method.dispatch.handler =
 		    parent_node->object->device.handler;
 	}
 
diff --git a/drivers/acpi/acpica/nsxfname.c b/drivers/acpi/acpica/nsxfname.c
index b01e45a415e3..0a26d73e050a 100644
--- a/drivers/acpi/acpica/nsxfname.c
+++ b/drivers/acpi/acpica/nsxfname.c
@@ -603,10 +603,9 @@ acpi_status acpi_install_method(u8 *buffer)
 	method_obj->method.param_count = (u8)
 	    (method_flags & AML_METHOD_ARG_COUNT);
 
-	method_obj->method.method_flags = (u8)
-	    (method_flags & ~AML_METHOD_ARG_COUNT);
-
 	if (method_flags & AML_METHOD_SERIALIZED) {
+		method_obj->method.info_flags = ACPI_METHOD_SERIALIZED;
+
 		method_obj->method.sync_level = (u8)
 		    ((method_flags & AML_METHOD_SYNC_LEVEL) >> 4);
 	}
diff --git a/drivers/acpi/acpica/psloop.c b/drivers/acpi/acpica/psloop.c
index 2f2e7760938c..06edeaf3b5e5 100644
--- a/drivers/acpi/acpica/psloop.c
+++ b/drivers/acpi/acpica/psloop.c
@@ -655,7 +655,7 @@ acpi_ps_link_module_code(union acpi_parse_object *parent_op,
 		method_obj->method.aml_start = aml_start;
 		method_obj->method.aml_length = aml_length;
 		method_obj->method.owner_id = owner_id;
-		method_obj->method.flags |= AOPOBJ_MODULE_LEVEL;
+		method_obj->method.info_flags |= ACPI_METHOD_MODULE_LEVEL;
 
 		/*
 		 * Save the parent node in next_object. This is cheating, but we
diff --git a/drivers/acpi/acpica/psparse.c b/drivers/acpi/acpica/psparse.c
index 8d81542194d4..3b8de113b571 100644
--- a/drivers/acpi/acpica/psparse.c
+++ b/drivers/acpi/acpica/psparse.c
@@ -55,7 +55,6 @@
 #include "acparser.h"
 #include "acdispat.h"
 #include "amlcode.h"
-#include "acnamesp.h"
 #include "acinterp.h"
 
 #define _COMPONENT          ACPI_PARSER
@@ -539,24 +538,16 @@ acpi_status acpi_ps_parse_aml(struct acpi_walk_state *walk_state)
 			/* Check for possible multi-thread reentrancy problem */
 
 			if ((status == AE_ALREADY_EXISTS) &&
-			    (!walk_state->method_desc->method.mutex)) {
-				ACPI_INFO((AE_INFO,
-					   "Marking method %4.4s as Serialized because of AE_ALREADY_EXISTS error",
-					   walk_state->method_node->name.
-					   ascii));
-
+			    (!(walk_state->method_desc->method.
+			       info_flags & ACPI_METHOD_SERIALIZED))) {
 				/*
-				 * Method tried to create an object twice. The probable cause is
-				 * that the method cannot handle reentrancy.
-				 *
-				 * The method is marked not_serialized, but it tried to create
-				 * a named object, causing the second thread entrance to fail.
-				 * Workaround this problem by marking the method permanently
-				 * as Serialized.
+				 * Method is not serialized and tried to create an object
+				 * twice. The probable cause is that the method cannot
+				 * handle reentrancy. Mark as "pending serialized" now, and
+				 * then mark "serialized" when the last thread exits.
 				 */
-				walk_state->method_desc->method.method_flags |=
-				    AML_METHOD_SERIALIZED;
-				walk_state->method_desc->method.sync_level = 0;
+				walk_state->method_desc->method.info_flags |=
+				    ACPI_METHOD_SERIALIZED_PENDING;
 			}
 		}
 
diff --git a/drivers/acpi/acpica/psxface.c b/drivers/acpi/acpica/psxface.c
index c42f067cff9d..bc49a80c386d 100644
--- a/drivers/acpi/acpica/psxface.c
+++ b/drivers/acpi/acpica/psxface.c
@@ -47,7 +47,6 @@
 #include "acdispat.h"
 #include "acinterp.h"
 #include "actables.h"
-#include "amlcode.h"
 
 #define _COMPONENT          ACPI_PARSER
 ACPI_MODULE_NAME("psxface")
@@ -285,15 +284,15 @@ acpi_status acpi_ps_execute_method(struct acpi_evaluate_info *info)
 		goto cleanup;
 	}
 
-	if (info->obj_desc->method.flags & AOPOBJ_MODULE_LEVEL) {
+	if (info->obj_desc->method.info_flags & ACPI_METHOD_MODULE_LEVEL) {
 		walk_state->parse_flags |= ACPI_PARSE_MODULE_LEVEL;
 	}
 
 	/* Invoke an internal method if necessary */
 
-	if (info->obj_desc->method.method_flags & AML_METHOD_INTERNAL_ONLY) {
+	if (info->obj_desc->method.info_flags & ACPI_METHOD_INTERNAL_ONLY) {
 		status =
-		    info->obj_desc->method.extra.implementation(walk_state);
+		    info->obj_desc->method.dispatch.implementation(walk_state);
 		info->return_object = walk_state->return_desc;
 
 		/* Cleanup states */