1 files changed, 46 insertions, 36 deletions

diff --git a/drivers/acpi/namespace/nssearch.c b/drivers/acpi/namespace/nssearch.c
index d2473476afa5..500e2bbcfaf7 100644
--- a/drivers/acpi/namespace/nssearch.c
+++ b/drivers/acpi/namespace/nssearch.c
@@ -56,16 +56,16 @@ acpi_ns_search_parent_tree(u32 target_name,
 
 /*******************************************************************************
  *
- * FUNCTION:    acpi_ns_search_node
+ * FUNCTION:    acpi_ns_search_one_scope
  *
  * PARAMETERS:  target_name     - Ascii ACPI name to search for
- *              Node            - Starting node where search will begin
+ *              parent_node     - Starting node where search will begin
  *              Type            - Object type to match
  *              return_node     - Where the matched Named obj is returned
  *
  * RETURN:      Status
  *
- * DESCRIPTION: Search a single level of the namespace.  Performs a
+ * DESCRIPTION: Search a single level of the namespace. Performs a
  *              simple search of the specified level, and does not add
  *              entries or search parents.
  *
@@ -75,32 +75,37 @@ acpi_ns_search_parent_tree(u32 target_name,
  *
  *      All namespace searching is linear in this implementation, but
  *      could be easily modified to support any improved search
- *      algorithm.  However, the linear search was chosen for simplicity
+ *      algorithm. However, the linear search was chosen for simplicity
  *      and because the trees are small and the other interpreter
  *      execution overhead is relatively high.
  *
+ *      Note: CPU execution analysis has shown that the AML interpreter spends
+ *      a very small percentage of its time searching the namespace. Therefore,
+ *      the linear search seems to be sufficient, as there would seem to be
+ *      little value in improving the search.
+ *
  ******************************************************************************/
 
 acpi_status
-acpi_ns_search_node(u32 target_name,
-                    struct acpi_namespace_node *node,
-                    acpi_object_type type,
-                    struct acpi_namespace_node **return_node)
+acpi_ns_search_one_scope(u32 target_name,
+                         struct acpi_namespace_node *parent_node,
+                         acpi_object_type type,
+                         struct acpi_namespace_node **return_node)
 {
-        struct acpi_namespace_node *next_node;
+        struct acpi_namespace_node *node;
 
-        ACPI_FUNCTION_TRACE(ns_search_node);
+        ACPI_FUNCTION_TRACE(ns_search_one_scope);
 
 #ifdef ACPI_DEBUG_OUTPUT
         if (ACPI_LV_NAMES & acpi_dbg_level) {
                 char *scope_name;
 
-                scope_name = acpi_ns_get_external_pathname(node);
+                scope_name = acpi_ns_get_external_pathname(parent_node);
                 if (scope_name) {
                         ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
                                           "Searching %s (%p) For [%4.4s] (%s)\n",
-                                          scope_name, node, ACPI_CAST_PTR(char,
-                                                                          &target_name),
+                                          scope_name, parent_node,
+                                          ACPI_CAST_PTR(char, &target_name),
                                           acpi_ut_get_type_name(type)));
 
                         ACPI_FREE(scope_name);
@@ -112,20 +117,20 @@ acpi_ns_search_node(u32 target_name,
          * Search for name at this namespace level, which is to say that we
          * must search for the name among the children of this object
          */
-        next_node = node->child;
-        while (next_node) {
+        node = parent_node->child;
+        while (node) {
 
                 /* Check for match against the name */
 
-                if (next_node->name.integer == target_name) {
+                if (node->name.integer == target_name) {
 
                         /* Resolve a control method alias if any */
 
-                        if (acpi_ns_get_type(next_node) ==
+                        if (acpi_ns_get_type(node) ==
                             ACPI_TYPE_LOCAL_METHOD_ALIAS) {
-                                next_node =
+                                node =
                                     ACPI_CAST_PTR(struct acpi_namespace_node,
-                                                  next_node->object);
+                                                  node->object);
                         }
 
                         /* Found matching entry */
@@ -133,12 +138,12 @@ acpi_ns_search_node(u32 target_name,
                         ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
                                           "Name [%4.4s] (%s) %p found in scope [%4.4s] %p\n",
                                           ACPI_CAST_PTR(char, &target_name),
-                                          acpi_ut_get_type_name(next_node->
-                                                                type),
-                                          next_node,
-                                          acpi_ut_get_node_name(node), node));
+                                          acpi_ut_get_type_name(node->type),
+                                          node,
+                                          acpi_ut_get_node_name(parent_node),
+                                          parent_node));
 
-                        *return_node = next_node;
+                        *return_node = node;
                         return_ACPI_STATUS(AE_OK);
                 }
 
@@ -146,7 +151,7 @@ acpi_ns_search_node(u32 target_name,
                  * The last entry in the list points back to the parent,
                  * so a flag is used to indicate the end-of-list
                  */
-                if (next_node->flags & ANOBJ_END_OF_PEER_LIST) {
+                if (node->flags & ANOBJ_END_OF_PEER_LIST) {
 
                         /* Searched entire list, we are done */
 
@@ -155,7 +160,7 @@ acpi_ns_search_node(u32 target_name,
 
                 /* Didn't match name, move on to the next peer object */
 
-                next_node = next_node->peer;
+                node = node->peer;
         }
 
         /* Searched entire namespace level, not found */
@@ -164,7 +169,8 @@ acpi_ns_search_node(u32 target_name,
                           "Name [%4.4s] (%s) not found in search in scope [%4.4s] %p first child %p\n",
                           ACPI_CAST_PTR(char, &target_name),
                           acpi_ut_get_type_name(type),
-                          acpi_ut_get_node_name(node), node, node->child));
+                          acpi_ut_get_node_name(parent_node), parent_node,
+                          parent_node->child));
 
         return_ACPI_STATUS(AE_NOT_FOUND);
 }
@@ -181,14 +187,14 @@ acpi_ns_search_node(u32 target_name,
  * RETURN:      Status
  *
  * DESCRIPTION: Called when a name has not been found in the current namespace
- *              level.  Before adding it or giving up, ACPI scope rules require
+ *              level. Before adding it or giving up, ACPI scope rules require
  *              searching enclosing scopes in cases identified by acpi_ns_local().
  *
  *              "A name is located by finding the matching name in the current
  *              name space, and then in the parent name space. If the parent
  *              name space does not contain the name, the search continues
  *              recursively until either the name is found or the name space
- *              does not have a parent (the root of the name space).  This
+ *              does not have a parent (the root of the name space). This
  *              indicates that the name is not found" (From ACPI Specification,
  *              section 5.3)
  *
@@ -237,11 +243,12 @@ acpi_ns_search_parent_tree(u32 target_name,
          */
         while (parent_node) {
                 /*
-                 * Search parent scope.  Use TYPE_ANY because we don't care about the
+                 * Search parent scope. Use TYPE_ANY because we don't care about the
                  * object type at this point, we only care about the existence of
-                 * the actual name we are searching for.  Typechecking comes later.
+                 * the actual name we are searching for. Typechecking comes later.
                  */
-                status = acpi_ns_search_node(target_name, parent_node,
+                status =
+                    acpi_ns_search_one_scope(target_name, parent_node,
                                              ACPI_TYPE_ANY, return_node);
                 if (ACPI_SUCCESS(status)) {
                         return_ACPI_STATUS(status);
@@ -273,7 +280,7 @@ acpi_ns_search_parent_tree(u32 target_name,
  * RETURN:      Status
  *
  * DESCRIPTION: Search for a name segment in a single namespace level,
- *              optionally adding it if it is not found.  If the passed
+ *              optionally adding it if it is not found. If the passed
  *              Type is not Any and the type previously stored in the
  *              entry was Any (i.e. unknown), update the stored type.
  *
@@ -332,7 +339,7 @@ acpi_ns_search_and_enter(u32 target_name,
         /* Try to find the name in the namespace level specified by the caller */
 
         *return_node = ACPI_ENTRY_NOT_FOUND;
-        status = acpi_ns_search_node(target_name, node, type, return_node);
+        status = acpi_ns_search_one_scope(target_name, node, type, return_node);
         if (status != AE_NOT_FOUND) {
                 /*
                  * If we found it AND the request specifies that a find is an error,
@@ -348,10 +355,10 @@ acpi_ns_search_and_enter(u32 target_name,
         }
 
         /*
-         * The name was not found.  If we are NOT performing the first pass
+         * The name was not found. If we are NOT performing the first pass
          * (name entry) of loading the namespace, search the parent tree (all the
          * way to the root if necessary.) We don't want to perform the parent
-         * search when the namespace is actually being loaded.  We want to perform
+         * search when the namespace is actually being loaded. We want to perform
          * the search when namespace references are being resolved (load pass 2)
          * and during the execution phase.
          */
@@ -386,6 +393,9 @@ acpi_ns_search_and_enter(u32 target_name,
                 return_ACPI_STATUS(AE_NO_MEMORY);
         }
 #ifdef ACPI_ASL_COMPILER
+        /*
+         * Node is an object defined by an External() statement
+         */
         if (flags & ACPI_NS_EXTERNAL) {
                 new_node->flags |= ANOBJ_IS_EXTERNAL;
         }