[PATCH v2 02/14] firewire: core: Open-code topology list walk

Kaitao Cheng <[email protected]> Tue, 9 Jun 2026 14:13:35 +0800
Newsgroups gmane.linux.ports.tegra,gmane.linux.kernel.drbd.devel,gmane.linux.block,gmane.linux.kernel.firewire.devel,gmane.comp.video.dri.devel,gmane.comp.freedesktop.xorg.drivers.intel,gmane.linux.kernel.spi.devel,gmane.linux.ports.arm.kernel,gmane.linux.sound,gmane.linux.kernel
Message-ID <[email protected]>
From: Kaitao Cheng <chengkaitao-UOlijcLmZ/[email protected]>

A later change will make list_for_each_entry() cache the next element
before entering the loop body. for_each_fw_node() intentionally appends
newly discovered child nodes to the temporary walk list while the list is
being traversed.

Keep the loop open-coded so the next node is looked up only after
children have been appended. This preserves the current breadth-first
traversal semantics and prepares the code for the list iterator update.

Signed-off-by: Kaitao Cheng <chengkaitao-UOlijcLmZ/[email protected]>
---
 drivers/firewire/core-topology.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/firewire/core-topology.c b/drivers/firewire/core-topology.c
index bb2d2db30795..df2ac0dab106 100644
--- a/drivers/firewire/core-topology.c
+++ b/drivers/firewire/core-topology.c
@@ -272,7 +272,9 @@ static void for_each_fw_node(struct fw_card *card, struct fw_node *root,
 	fw_node_get(root);
 	list_add_tail(&root->link, &list);
 	parent = NULL;
-	list_for_each_entry(node, &list, link) {
+	for (node = list_first_entry(&list, typeof(*node), link);
+	     !list_entry_is_head(node, &list, link);
+	     node = list_next_entry(node, link)) {
 		node->color = card->color;
 
 		for (i = 0; i < node->port_count; i++) {
-- 
2.43.0