* @pos: the css * to use as the loop cursor
* @root: css whose descendants to walk
*
- * Walk @root's descendants. Must be called under rcu_read_lock(). A
+ * Walk @root's descendants. @root is included in the iteration and the
+ * first node to be visited. Must be called under rcu_read_lock(). A
* descendant css which hasn't finished ->css_online() or already has
* finished ->css_offline() may show up during traversal and it's each
* subsystem's responsibility to verify that each @pos is alive.
*
* my_update_state(@css)
* {
- * Lock @css;
- * Update @css's state;
- * Unlock @css;
- *
* css_for_each_descendant_pre(@pos, @css) {
* Lock @pos;
- * Verify @pos is alive and inherit state from @pos's parent;
+ * if (@pos == @css)
+ * Update @css's state;
+ * else
+ * Verify @pos is alive and inherit state from its parent;
* Unlock @pos;
* }
* }
* @css: css whose descendants to walk
*
* Similar to css_for_each_descendant_pre() but performs post-order
- * traversal instead. Note that the walk visibility guarantee described in
- * pre-order walk doesn't apply the same to post-order walks.
+ * traversal instead. @root is included in the iteration and the last
+ * node to be visited. Note that the walk visibility guarantee described
+ * in pre-order walk doesn't apply the same to post-order walks.
*/
#define css_for_each_descendant_post(pos, css) \
for ((pos) = css_next_descendant_post(NULL, (css)); (pos); \