ACPICA: Update comments

Signed-off-by: Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

diff --git a/drivers/acpi/namespace/nswalk.c b/drivers/acpi/namespace/nswalk.c
index a138fcb..c6619d8 100644 (file)
--- a/drivers/acpi/namespace/nswalk.c
+++ b/drivers/acpi/namespace/nswalk.c
@@ -193,21 +193,28 @@ acpi_ns_walk_namespace(acpi_object_type type,
                    acpi_ns_get_next_node(ACPI_TYPE_ANY, parent_node,
                                          child_node);
                if (child_node) {
-                       /*
-                        * Found node, Get the type if we are not
-                        * searching for ANY
-                        */
+
+                       /* Found node, Get the type if we are not searching for ANY */
+
                        if (type != ACPI_TYPE_ANY) {
                                child_type = child_node->type;
                        }
 
+                       /*
+                        * 1) Type must match
+                        * 2) Permanent namespace nodes are OK
+                        * 3) Ignore temporary nodes unless told otherwise. Typically,
+                        *    the temporary nodes can cause a race condition where they can
+                        *    be deleted during the execution of the user function. Only the
+                        *    debugger namespace dump will examine the temporary nodes.
+                        */
                        if ((child_type == type) &&
                            (!(child_node->flags & ANOBJ_TEMPORARY) ||
                             (child_node->flags & ANOBJ_TEMPORARY)
                             && (flags & ACPI_NS_WALK_TEMP_NODES))) {
                                /*
-                                * Found a matching node, invoke the user
-                                * callback function
+                                * Found a matching node, invoke the user callback function.
+                                * Unlock the namespace if flag is set.
                                 */
                                if (flags & ACPI_NS_WALK_UNLOCK) {
                                        mutex_status =
@@ -219,8 +226,9 @@ acpi_ns_walk_namespace(acpi_object_type type,
                                        }
                                }
 
-                               status = user_function(child_node, level,
-                                                      context, return_value);
+                               status =
+                                   user_function(child_node, level, context,
+                                                 return_value);
 
                                if (flags & ACPI_NS_WALK_UNLOCK) {
                                        mutex_status =
@@ -254,20 +262,17 @@ acpi_ns_walk_namespace(acpi_object_type type,
                        }
 
                        /*
-                        * Depth first search:
-                        * Attempt to go down another level in the namespace
-                        * if we are allowed to.  Don't go any further if we
-                        * have reached the caller specified maximum depth
-                        * or if the user function has specified that the
-                        * maximum depth has been reached.
+                        * Depth first search: Attempt to go down another level in the
+                        * namespace if we are allowed to.  Don't go any further if we have
+                        * reached the caller specified maximum depth or if the user
+                        * function has specified that the maximum depth has been reached.
                         */
                        if ((level < max_depth) && (status != AE_CTRL_DEPTH)) {
                                if (acpi_ns_get_next_node
                                    (ACPI_TYPE_ANY, child_node, NULL)) {
-                                       /*
-                                        * There is at least one child of this
-                                        * node, visit the onde
-                                        */
+
+                                       /* There is at least one child of this node, visit it */
+
                                        level++;
                                        parent_node = child_node;
                                        child_node = NULL;
@@ -275,9 +280,8 @@ acpi_ns_walk_namespace(acpi_object_type type,
                        }
                } else {
                        /*
-                        * No more children of this node (acpi_ns_get_next_node
-                        * failed), go back upwards in the namespace tree to
-                        * the node's parent.
+                        * No more children of this node (acpi_ns_get_next_node failed), go
+                        * back upwards in the namespace tree to the node's parent.
                         */
                        level--;
                        child_node = parent_node;