Re: [PATCH net] phy: mscc: Fix timestamping for vsc8584

[Vladimir Oltean <olteanv@gmail.com>]

On Mon, Aug 04, 2025 at 09:39:40AM +0200, Horatiu Vultur wrote:
> I think it is a great idea. I can map struct vsc8531_skb directly on
> skb->cb and then drop the allocation.

Ok.

Another set of suggestions on the patch, all regarding list processing:

1 - shouldn't you use list_add_tail() rather than list_add() towards
    &vsc8531->rx_skbs_list? I am concerned that with multiple RX
    timestampable skbs in flight, you would be processing them in
    "stack" rather than "queue" order, effectively reordering them.

2 - you can use list_move_tail() to move an item from a list to another,
    or you can just call list_splice_tail_init() to move the entire
    contents of &priv->rx_skbs_list onto a separate on-stack list from
    which you later dequeue, and at the same time reinitialize
    &priv->rx_skbs_list to an empty queue. If you do that, you can
    shorten the atomic section with &priv->rx_skbs_lock, to just around
    the list_splice_tail_init() call.

3 - the following:

	struct list_head skbs;

	INIT_LIST_HEAD(&skbs);

can be simplified to:

	LIST_HEAD(skbs);

which combines initialization and declaration.