net: prefech skb->priority in __dev_xmit_skb()

Most qdiscs need to read skb->priority at enqueue time().

In commit 100dfa74ca ("net: dev_queue_xmit() llist adoption")
I added a prefetch(next), lets add another one for the second
half of skb.

Note that skb->priority and skb->hash share a common cache line,
so this patch helps qdiscs needing both fields.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20251121083256.674562-11-edumazet@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
This commit is contained in:
Eric Dumazet
2025-11-21 08:32:52 +00:00
committed by Paolo Abeni
parent 2f9babc04d
commit b2e9821cff

View File

@@ -4246,6 +4246,7 @@ static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
llist_for_each_entry_safe(skb, next, ll_list, ll_node) {
prefetch(next);
prefetch(&next->priority);
skb_mark_not_on_list(skb);
rc = dev_qdisc_enqueue(skb, q, &to_free, txq);
count++;