From: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> To avoid issues with out of order cleanup, or ambiguity about when the auto freed data is first instantiated, do it within the for loop definition. The disadvantage is that the struct device_node *child variable creation is not immediately obvious where this is used. However, in many cases, if there is another definition of struct device_node *child; the compiler / static analysers will notify us that it is unused, or uninitialized. Note that, in the vast majority of cases, the _available_ form should be used and as code is converted to these scoped handers, we should confirm that any cases that do not check for available have a good reason not to. Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> --- include/linux/of.h | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/include/linux/of.h b/include/linux/of.h index 50e882ee91da..024dda54b9c7 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -1430,10 +1430,23 @@ static inline int of_property_read_s32(const struct device_node *np, #define for_each_child_of_node(parent, child) \ for (child = of_get_next_child(parent, NULL); child != NULL; \ child = of_get_next_child(parent, child)) + +#define for_each_child_of_node_scoped(parent, child) \ + for (struct device_node *child __free(device_node) = \ + of_get_next_child(parent, NULL); \ + child != NULL; \ + child = of_get_next_child(parent, child)) + #define for_each_available_child_of_node(parent, child) \ for (child = of_get_next_available_child(parent, NULL); child != NULL; \ child = of_get_next_available_child(parent, child)) +#define for_each_available_child_of_node_scoped(parent, child) \ + for (struct device_node *child __free(device_node) = \ + of_get_next_available_child(parent, NULL); \ + child != NULL; \ + child = of_get_next_available_child(parent, child)) + #define for_each_of_cpu_node(cpu) \ for (cpu = of_get_next_cpu_node(NULL); cpu != NULL; \ cpu = of_get_next_cpu_node(cpu)) -- 2.44.0
