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>

1 files changed, 1 insertions, 1 deletions

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);