ACPICA: Performance enhancement for namespace search and access

This change enhances the performance of namespace searches and
walks by adding a backpointer to the parent in each namespace
node. On large namespaces, this change can improve overall ACPI
performance by up to 9X.  Adding a pointer to each namespace node
increases the overall size of the internal namespace by about 5%,
since each namespace entry usually consists of both a namespace
node and an ACPI operand object.

Signed-off-by: Alexey Starikovskiy <astarikovskiy@suse.de>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

15 files changed, 52 insertions, 218 deletions

diff --git a/drivers/acpi/acpica/aclocal.h b/drivers/acpi/acpica/aclocal.h
index 147a7e6bd38f..eb2d420b39ec 100644
--- a/drivers/acpi/acpica/aclocal.h
+++ b/drivers/acpi/acpica/aclocal.h
@@ -184,8 +184,9 @@ struct acpi_namespace_node {
         u8 flags;               /* Miscellaneous flags */
         acpi_owner_id owner_id; /* Node creator */
         union acpi_name_union name;     /* ACPI Name, always 4 chars per ACPI spec */
+        struct acpi_namespace_node *parent;     /* Parent node */
         struct acpi_namespace_node *child;      /* First child */
-        struct acpi_namespace_node *peer;       /* Peer. Parent if ANOBJ_END_OF_PEER_LIST set */
+        struct acpi_namespace_node *peer;       /* First peer */
 
         /*
          * The following fields are used by the ASL compiler and disassembler only
@@ -199,7 +200,7 @@ struct acpi_namespace_node {
 
 /* Namespace Node flags */
 
-#define ANOBJ_END_OF_PEER_LIST          0x01    /* End-of-list, Peer field points to parent */
+#define ANOBJ_RESERVED                  0x01    /* Available for use */
 #define ANOBJ_TEMPORARY                 0x02    /* Node is create by a method and is temporary */
 #define ANOBJ_METHOD_ARG                0x04    /* Node is a method argument */
 #define ANOBJ_METHOD_LOCAL              0x08    /* Node is a method local */
diff --git a/drivers/acpi/acpica/acnamesp.h b/drivers/acpi/acpica/acnamesp.h
index 258159cfcdfa..9f60ff002203 100644
--- a/drivers/acpi/acpica/acnamesp.h
+++ b/drivers/acpi/acpica/acnamesp.h
@@ -369,11 +369,4 @@ struct acpi_namespace_node *acpi_ns_validate_handle(acpi_handle handle);
 
 void acpi_ns_terminate(void);
 
-struct acpi_namespace_node *acpi_ns_get_parent_node(struct acpi_namespace_node
-                                                    *node);
-
-struct acpi_namespace_node *acpi_ns_get_next_valid_node(struct
-                                                        acpi_namespace_node
-                                                        *node);
-
 #endif                          /* __ACNAMESP_H__ */
diff --git a/drivers/acpi/acpica/dsmthdat.c b/drivers/acpi/acpica/dsmthdat.c
index d5e927f818a0..8095306fcd8c 100644
--- a/drivers/acpi/acpica/dsmthdat.c
+++ b/drivers/acpi/acpica/dsmthdat.c
@@ -102,8 +102,7 @@ void acpi_ds_method_data_init(struct acpi_walk_state *walk_state)
                 walk_state->arguments[i].name.integer |= (i << 24);
                 walk_state->arguments[i].descriptor_type = ACPI_DESC_TYPE_NAMED;
                 walk_state->arguments[i].type = ACPI_TYPE_ANY;
-                walk_state->arguments[i].flags =
-                    ANOBJ_END_OF_PEER_LIST | ANOBJ_METHOD_ARG;
+                walk_state->arguments[i].flags = ANOBJ_METHOD_ARG;
         }
 
         /* Init the method locals */
@@ -116,8 +115,7 @@ void acpi_ds_method_data_init(struct acpi_walk_state *walk_state)
                 walk_state->local_variables[i].descriptor_type =
                     ACPI_DESC_TYPE_NAMED;
                 walk_state->local_variables[i].type = ACPI_TYPE_ANY;
-                walk_state->local_variables[i].flags =
-                    ANOBJ_END_OF_PEER_LIST | ANOBJ_METHOD_LOCAL;
+                walk_state->local_variables[i].flags = ANOBJ_METHOD_LOCAL;
         }
 
         return_VOID;
diff --git a/drivers/acpi/acpica/dsopcode.c b/drivers/acpi/acpica/dsopcode.c
index 53a7e416f33e..7c0e74227171 100644
--- a/drivers/acpi/acpica/dsopcode.c
+++ b/drivers/acpi/acpica/dsopcode.c
@@ -213,7 +213,7 @@ acpi_ds_get_buffer_field_arguments(union acpi_operand_object *obj_desc)
 
         /* Execute the AML code for the term_arg arguments */
 
-        status = acpi_ds_execute_arguments(node, acpi_ns_get_parent_node(node),
+        status = acpi_ds_execute_arguments(node, node->parent,
                                            extra_desc->extra.aml_length,
                                            extra_desc->extra.aml_start);
         return_ACPI_STATUS(status);
@@ -257,7 +257,7 @@ acpi_ds_get_bank_field_arguments(union acpi_operand_object *obj_desc)
 
         /* Execute the AML code for the term_arg arguments */
 
-        status = acpi_ds_execute_arguments(node, acpi_ns_get_parent_node(node),
+        status = acpi_ds_execute_arguments(node, node->parent,
                                            extra_desc->extra.aml_length,
                                            extra_desc->extra.aml_start);
         return_ACPI_STATUS(status);
@@ -394,7 +394,7 @@ acpi_status acpi_ds_get_region_arguments(union acpi_operand_object *obj_desc)
 
         /* Execute the argument AML */
 
-        status = acpi_ds_execute_arguments(node, acpi_ns_get_parent_node(node),
+        status = acpi_ds_execute_arguments(node, node->parent,
                                            extra_desc->extra.aml_length,
                                            extra_desc->extra.aml_start);
         if (ACPI_FAILURE(status)) {
diff --git a/drivers/acpi/acpica/evrgnini.c b/drivers/acpi/acpica/evrgnini.c
index 2e3b0334072f..f40d271bf568 100644
--- a/drivers/acpi/acpica/evrgnini.c
+++ b/drivers/acpi/acpica/evrgnini.c
@@ -199,7 +199,7 @@ acpi_ev_pci_config_region_setup(acpi_handle handle,
                 return_ACPI_STATUS(status);
         }
 
-        parent_node = acpi_ns_get_parent_node(region_obj->region.node);
+        parent_node = region_obj->region.node->parent;
 
         /*
          * Get the _SEG and _BBN values from the device upon which the handler
@@ -248,7 +248,7 @@ acpi_ev_pci_config_region_setup(acpi_handle handle,
                                 break;
                         }
 
-                        pci_root_node = acpi_ns_get_parent_node(pci_root_node);
+                        pci_root_node = pci_root_node->parent;
                 }
 
                 /* PCI root bridge not found, use namespace root node */
@@ -280,7 +280,7 @@ acpi_ev_pci_config_region_setup(acpi_handle handle,
          */
         pci_device_node = region_obj->region.node;
         while (pci_device_node && (pci_device_node->type != ACPI_TYPE_DEVICE)) {
-                pci_device_node = acpi_ns_get_parent_node(pci_device_node);
+                pci_device_node = pci_device_node->parent;
         }
 
         if (!pci_device_node) {
@@ -521,7 +521,7 @@ acpi_ev_initialize_region(union acpi_operand_object *region_obj,
                 return_ACPI_STATUS(AE_NOT_EXIST);
         }
 
-        node = acpi_ns_get_parent_node(region_obj->region.node);
+        node = region_obj->region.node->parent;
         space_id = region_obj->region.space_id;
 
         /* Setup defaults */
@@ -654,7 +654,7 @@ acpi_ev_initialize_region(union acpi_operand_object *region_obj,
 
                 /* This node does not have the handler we need; Pop up one level */
 
-                node = acpi_ns_get_parent_node(node);
+                node = node->parent;
         }
 
         /* If we get here, there is no handler for this region */
diff --git a/drivers/acpi/acpica/exdump.c b/drivers/acpi/acpica/exdump.c
index cdb66d1e3fde..f067bbb0d961 100644
--- a/drivers/acpi/acpica/exdump.c
+++ b/drivers/acpi/acpica/exdump.c
@@ -812,7 +812,7 @@ void acpi_ex_dump_namespace_node(struct acpi_namespace_node *node, u32 flags)
         acpi_ex_out_string("Type", acpi_ut_get_type_name(node->type));
         acpi_ex_out_pointer("Attached Object",
                             acpi_ns_get_attached_object(node));
-        acpi_ex_out_pointer("Parent", acpi_ns_get_parent_node(node));
+        acpi_ex_out_pointer("Parent", node->parent);
 
         acpi_ex_dump_object(ACPI_CAST_PTR(union acpi_operand_object, node),
                             acpi_ex_dump_node);
diff --git a/drivers/acpi/acpica/nsaccess.c b/drivers/acpi/acpica/nsaccess.c
index 2cebfa94b79a..0cd925be5fc1 100644
--- a/drivers/acpi/acpica/nsaccess.c
+++ b/drivers/acpi/acpica/nsaccess.c
@@ -338,8 +338,7 @@ acpi_ns_lookup(union acpi_generic_state *scope_info,
                          */
                         while (!acpi_ns_opens_scope(prefix_node->type) &&
                                prefix_node->type != ACPI_TYPE_ANY) {
-                                prefix_node =
-                                    acpi_ns_get_parent_node(prefix_node);
+                                prefix_node = prefix_node->parent;
                         }
                 }
         }
@@ -419,7 +418,7 @@ acpi_ns_lookup(union acpi_generic_state *scope_info,
                                 /* Backup to the parent node */
 
                                 num_carats++;
-                                this_node = acpi_ns_get_parent_node(this_node);
+                                this_node = this_node->parent;
                                 if (!this_node) {
 
                                         /* Current scope has no parent scope */
diff --git a/drivers/acpi/acpica/nsalloc.c b/drivers/acpi/acpica/nsalloc.c
index 982269c1fa48..8d3a43a061ab 100644
--- a/drivers/acpi/acpica/nsalloc.c
+++ b/drivers/acpi/acpica/nsalloc.c
@@ -159,7 +159,7 @@ void acpi_ns_remove_node(struct acpi_namespace_node *node)
 
         ACPI_FUNCTION_TRACE_PTR(ns_remove_node, node);
 
-        parent_node = acpi_ns_get_parent_node(node);
+        parent_node = node->parent;
 
         prev_node = NULL;
         next_node = parent_node->child;
@@ -168,29 +168,20 @@ void acpi_ns_remove_node(struct acpi_namespace_node *node)
 
         while (next_node != node) {
                 prev_node = next_node;
-                next_node = prev_node->peer;
+                next_node = next_node->peer;
         }
 
         if (prev_node) {
 
                 /* Node is not first child, unlink it */
 
-                prev_node->peer = next_node->peer;
-                if (next_node->flags & ANOBJ_END_OF_PEER_LIST) {
-                        prev_node->flags |= ANOBJ_END_OF_PEER_LIST;
-                }
+                prev_node->peer = node->peer;
         } else {
-                /* Node is first child (has no previous peer) */
-
-                if (next_node->flags & ANOBJ_END_OF_PEER_LIST) {
-
-                        /* No peers at all */
-
-                        parent_node->child = NULL;
-                } else {        /* Link peer list to parent */
-
-                        parent_node->child = next_node->peer;
-                }
+                /*
+                 * Node is first child (has no previous peer).
+                 * Link peer list to parent
+                 */
+                parent_node->child = node->peer;
         }
 
         /* Delete the node and any attached objects */
@@ -238,23 +229,20 @@ void acpi_ns_install_node(struct acpi_walk_state *walk_state, struct acpi_namesp
 
         /* Link the new entry into the parent and existing children */
 
+        node->peer = NULL;
+        node->parent = parent_node;
         child_node = parent_node->child;
+
         if (!child_node) {
                 parent_node->child = node;
-                node->flags |= ANOBJ_END_OF_PEER_LIST;
-                node->peer = parent_node;
         } else {
-                while (!(child_node->flags & ANOBJ_END_OF_PEER_LIST)) {
+                /* Add node to the end of the peer list */
+
+                while (child_node->peer) {
                         child_node = child_node->peer;
                 }
 
                 child_node->peer = node;
-
-                /* Clear end-of-list flag */
-
-                child_node->flags &= ~ANOBJ_END_OF_PEER_LIST;
-                node->flags |= ANOBJ_END_OF_PEER_LIST;
-                node->peer = parent_node;
         }
 
         /* Init the new entry */
@@ -288,9 +276,8 @@ void acpi_ns_install_node(struct acpi_walk_state *walk_state, struct acpi_namesp
 
 void acpi_ns_delete_children(struct acpi_namespace_node *parent_node)
 {
-        struct acpi_namespace_node *child_node;
         struct acpi_namespace_node *next_node;
-        u8 flags;
+        struct acpi_namespace_node *node_to_delete;
 
         ACPI_FUNCTION_TRACE_PTR(ns_delete_children, parent_node);
 
@@ -298,37 +285,26 @@ void acpi_ns_delete_children(struct acpi_namespace_node *parent_node)
                 return_VOID;
         }
 
-        /* If no children, all done! */
-
-        child_node = parent_node->child;
-        if (!child_node) {
-                return_VOID;
-        }
-
         /* Deallocate all children at this level */
 
-        do {
-
-                /* Get the things we need */
-
-                next_node = child_node->peer;
-                flags = child_node->flags;
+        next_node = parent_node->child;
+        while (next_node) {
 
                 /* Grandchildren should have all been deleted already */
 
-                if (child_node->child) {
+                if (next_node->child) {
                         ACPI_ERROR((AE_INFO, "Found a grandchild! P=%p C=%p",
-                                    parent_node, child_node));
+                                    parent_node, next_node));
                 }
 
                 /*
                  * Delete this child node and move on to the next child in the list.
                  * No need to unlink the node since we are deleting the entire branch.
                  */
-                acpi_ns_delete_node(child_node);
-                child_node = next_node;
-
-        } while (!(flags & ANOBJ_END_OF_PEER_LIST));
+                node_to_delete = next_node;
+                next_node = next_node->peer;
+                acpi_ns_delete_node(node_to_delete);
+        };
 
         /* Clear the parent's child pointer */
 
@@ -405,7 +381,7 @@ void acpi_ns_delete_namespace_subtree(struct acpi_namespace_node *parent_node)
 
                         /* Move up the tree to the grandparent */
 
-                        parent_node = acpi_ns_get_parent_node(parent_node);
+                        parent_node = parent_node->parent;
                 }
         }
 
@@ -510,7 +486,7 @@ void acpi_ns_delete_namespace_by_owner(acpi_owner_id owner_id)
 
                         /* Move up the tree to the grandparent */
 
-                        parent_node = acpi_ns_get_parent_node(parent_node);
+                        parent_node = parent_node->parent;
                 }
         }
 
diff --git a/drivers/acpi/acpica/nsinit.c b/drivers/acpi/acpica/nsinit.c
index f0e49df7c13b..660a2728908d 100644
--- a/drivers/acpi/acpica/nsinit.c
+++ b/drivers/acpi/acpica/nsinit.c
@@ -410,7 +410,7 @@ acpi_ns_find_ini_methods(acpi_handle obj_handle,
          * The only _INI methods that we care about are those that are
          * present under Device, Processor, and Thermal objects.
          */
-        parent_node = acpi_ns_get_parent_node(node);
+        parent_node = node->parent;
         switch (parent_node->type) {
         case ACPI_TYPE_DEVICE:
         case ACPI_TYPE_PROCESSOR:
@@ -420,7 +420,7 @@ acpi_ns_find_ini_methods(acpi_handle obj_handle,
 
                 while (parent_node) {
                         parent_node->flags |= ANOBJ_SUBTREE_HAS_INI;
-                        parent_node = acpi_ns_get_parent_node(parent_node);
+                        parent_node = parent_node->parent;
                 }
                 break;
 
diff --git a/drivers/acpi/acpica/nsnames.c b/drivers/acpi/acpica/nsnames.c
index 7dea0031605c..d3104af57e13 100644
--- a/drivers/acpi/acpica/nsnames.c
+++ b/drivers/acpi/acpica/nsnames.c
@@ -93,7 +93,7 @@ acpi_ns_build_external_path(struct acpi_namespace_node *node,
                 /* Put the name into the buffer */
 
                 ACPI_MOVE_32_TO_32((name_buffer + index), &parent_node->name);
-                parent_node = acpi_ns_get_parent_node(parent_node);
+                parent_node = parent_node->parent;
 
                 /* Prefix name with the path separator */
 
@@ -198,7 +198,7 @@ acpi_size acpi_ns_get_pathname_length(struct acpi_namespace_node *node)
                         return 0;
                 }
                 size += ACPI_PATH_SEGMENT_LENGTH;
-                next_node = acpi_ns_get_parent_node(next_node);
+                next_node = next_node->parent;
         }
 
         if (!size) {
diff --git a/drivers/acpi/acpica/nssearch.c b/drivers/acpi/acpica/nssearch.c
index a8e42b5e9463..41102a84272f 100644
--- a/drivers/acpi/acpica/nssearch.c
+++ b/drivers/acpi/acpica/nssearch.c
@@ -152,17 +152,6 @@ acpi_ns_search_one_scope(u32 target_name,
                         return_ACPI_STATUS(AE_OK);
                 }
 
-                /*
-                 * The last entry in the list points back to the parent,
-                 * so a flag is used to indicate the end-of-list
-                 */
-                if (node->flags & ANOBJ_END_OF_PEER_LIST) {
-
-                        /* Searched entire list, we are done */
-
-                        break;
-                }
-
                 /* Didn't match name, move on to the next peer object */
 
                 node = node->peer;
@@ -217,7 +206,7 @@ acpi_ns_search_parent_tree(u32 target_name,
 
         ACPI_FUNCTION_TRACE(ns_search_parent_tree);
 
-        parent_node = acpi_ns_get_parent_node(node);
+        parent_node = node->parent;
 
         /*
          * If there is no parent (i.e., we are at the root) or type is "local",
@@ -261,7 +250,7 @@ acpi_ns_search_parent_tree(u32 target_name,
 
                 /* Not found here, go up another level (until we reach the root) */
 
-                parent_node = acpi_ns_get_parent_node(parent_node);
+                parent_node = parent_node->parent;
         }
 
         /* Not found in parent tree */
diff --git a/drivers/acpi/acpica/nsutils.c b/drivers/acpi/acpica/nsutils.c
index bab559712da1..e1add3491b04 100644
--- a/drivers/acpi/acpica/nsutils.c
+++ b/drivers/acpi/acpica/nsutils.c
@@ -847,116 +847,3 @@ acpi_ns_get_node(struct acpi_namespace_node *prefix_node,
         ACPI_FREE(internal_path);
         return_ACPI_STATUS(status);
 }
-
-/*******************************************************************************
- *
- * FUNCTION:    acpi_ns_get_parent_node
- *
- * PARAMETERS:  Node       - Current table entry
- *
- * RETURN:      Parent entry of the given entry
- *
- * DESCRIPTION: Obtain the parent entry for a given entry in the namespace.
- *
- ******************************************************************************/
-
-struct acpi_namespace_node *acpi_ns_get_parent_node(struct acpi_namespace_node
-                                                    *node)
-{
-        ACPI_FUNCTION_ENTRY();
-
-        if (!node) {
-                return (NULL);
-        }
-
-        /*
-         * Walk to the end of this peer list. The last entry is marked with a flag
-         * and the peer pointer is really a pointer back to the parent. This saves
-         * putting a parent back pointer in each and every named object!
-         */
-        while (!(node->flags & ANOBJ_END_OF_PEER_LIST)) {
-                node = node->peer;
-        }
-
-        return (node->peer);
-}
-
-/*******************************************************************************
- *
- * FUNCTION:    acpi_ns_get_next_valid_node
- *
- * PARAMETERS:  Node       - Current table entry
- *
- * RETURN:      Next valid Node in the linked node list. NULL if no more valid
- *              nodes.
- *
- * DESCRIPTION: Find the next valid node within a name table.
- *              Useful for implementing NULL-end-of-list loops.
- *
- ******************************************************************************/
-
-struct acpi_namespace_node *acpi_ns_get_next_valid_node(struct
-                                                        acpi_namespace_node
-                                                        *node)
-{
-
-        /* If we are at the end of this peer list, return NULL */
-
-        if (node->flags & ANOBJ_END_OF_PEER_LIST) {
-                return NULL;
-        }
-
-        /* Otherwise just return the next peer */
-
-        return (node->peer);
-}
-
-#ifdef ACPI_OBSOLETE_FUNCTIONS
-/*******************************************************************************
- *
- * FUNCTION:    acpi_ns_find_parent_name
- *
- * PARAMETERS:  *child_node            - Named Obj whose name is to be found
- *
- * RETURN:      The ACPI name
- *
- * DESCRIPTION: Search for the given obj in its parent scope and return the
- *              name segment, or "????" if the parent name can't be found
- *              (which "should not happen").
- *
- ******************************************************************************/
-
-acpi_name acpi_ns_find_parent_name(struct acpi_namespace_node * child_node)
-{
-        struct acpi_namespace_node *parent_node;
-
-        ACPI_FUNCTION_TRACE(ns_find_parent_name);
-
-        if (child_node) {
-
-                /* Valid entry.  Get the parent Node */
-
-                parent_node = acpi_ns_get_parent_node(child_node);
-                if (parent_node) {
-                        ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
-                                          "Parent of %p [%4.4s] is %p [%4.4s]\n",
-                                          child_node,
-                                          acpi_ut_get_node_name(child_node),
-                                          parent_node,
-                                          acpi_ut_get_node_name(parent_node)));
-
-                        if (parent_node->name.integer) {
-                                return_VALUE((acpi_name) parent_node->name.
-                                             integer);
-                        }
-                }
-
-                ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
-                                  "Unable to find parent of %p (%4.4s)\n",
-                                  child_node,
-                                  acpi_ut_get_node_name(child_node)));
-        }
-
-        return_VALUE(ACPI_UNKNOWN_NAME);
-}
-#endif
diff --git a/drivers/acpi/acpica/nswalk.c b/drivers/acpi/acpica/nswalk.c
index 00e79fb26029..2cd5be8fe10f 100644
--- a/drivers/acpi/acpica/nswalk.c
+++ b/drivers/acpi/acpica/nswalk.c
@@ -79,15 +79,6 @@ struct acpi_namespace_node *acpi_ns_get_next_node(struct acpi_namespace_node
                 return parent_node->child;
         }
 
-        /*
-         * Get the next node.
-         *
-         * If we are at the end of this peer list, return NULL
-         */
-        if (child_node->flags & ANOBJ_END_OF_PEER_LIST) {
-                return NULL;
-        }
-
         /* Otherwise just return the next peer */
 
         return child_node->peer;
@@ -146,9 +137,9 @@ struct acpi_namespace_node *acpi_ns_get_next_node_typed(acpi_object_type type,
                         return (next_node);
                 }
 
-                /* Otherwise, move on to the next node */
+                /* Otherwise, move on to the next peer node */
 
-                next_node = acpi_ns_get_next_valid_node(next_node);
+                next_node = next_node->peer;
         }
 
         /* Not found */
@@ -355,7 +346,7 @@ acpi_ns_walk_namespace(acpi_object_type type,
                          */
                         level--;
                         child_node = parent_node;
-                        parent_node = acpi_ns_get_parent_node(parent_node);
+                        parent_node = parent_node->parent;
 
                         node_previously_visited = TRUE;
                 }
diff --git a/drivers/acpi/acpica/nsxfobj.c b/drivers/acpi/acpica/nsxfobj.c
index eafef24ea448..a1f04e9b8030 100644
--- a/drivers/acpi/acpica/nsxfobj.c
+++ b/drivers/acpi/acpica/nsxfobj.c
@@ -190,7 +190,7 @@ acpi_status acpi_get_parent(acpi_handle handle, acpi_handle * ret_handle)
 
         /* Get the parent entry */
 
-        parent_node = acpi_ns_get_parent_node(node);
+        parent_node = node->parent;
         *ret_handle = ACPI_CAST_PTR(acpi_handle, parent_node);
 
         /* Return exception if parent is null */
diff --git a/drivers/acpi/acpica/utglobal.c b/drivers/acpi/acpica/utglobal.c
index 66116750a0f9..0558747579ef 100644
--- a/drivers/acpi/acpica/utglobal.c
+++ b/drivers/acpi/acpica/utglobal.c
@@ -813,10 +813,10 @@ acpi_status acpi_ut_init_globals(void)
         acpi_gbl_root_node_struct.name.integer = ACPI_ROOT_NAME;
         acpi_gbl_root_node_struct.descriptor_type = ACPI_DESC_TYPE_NAMED;
         acpi_gbl_root_node_struct.type = ACPI_TYPE_DEVICE;
+        acpi_gbl_root_node_struct.parent = NULL;
         acpi_gbl_root_node_struct.child = NULL;
         acpi_gbl_root_node_struct.peer = NULL;
         acpi_gbl_root_node_struct.object = NULL;
-        acpi_gbl_root_node_struct.flags = ANOBJ_END_OF_PEER_LIST;
 
 #ifdef ACPI_DEBUG_OUTPUT
         acpi_gbl_lowest_stack_pointer = ACPI_CAST_PTR(acpi_size, ACPI_SIZE_MAX);