Software segmentation exposes the complete skb list before encryption begins. While encrypting each segment, request write ownership of the next linear segment cache line by cache line. A single skb naturally skips the prefetch path.
Signed-off-by: Ralf Lici <[email protected]> --- No changes since v3 https://lore.kernel.org/openvpn-devel/cc6cda4eb421a6c1ba12da441256b4dfb8438c12.1789546917.git.r...@mandelbit.com/ No changes since v2 https://lore.kernel.org/openvpn-devel/3f903692549ee58887b1bb421f8b283059f66a1d.1789540779.git.r...@mandelbit.com/ No changes since v1 https://lore.kernel.org/openvpn-devel/382879c187b1acca65198c467d1263266243ea50.1789485693.git.r...@mandelbit.com/ drivers/net/ovpn/io.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c index 11f7f16d7b79..cb7503a3e79c 100644 --- a/drivers/net/ovpn/io.c +++ b/drivers/net/ovpn/io.c @@ -472,6 +472,12 @@ static void ovpn_send(struct ovpn_priv *ovpn, struct sk_buff *skb, * independently */ skb_list_walk_safe(skb, curr, next) { + /* encrypting this segment can hide the cost of fetching the + * next segment's data into the cache + */ + if (next) + ovpn_skb_prefetchw(next); + if (unlikely(!ovpn_encrypt_one(peer, curr))) { ovpn_dev_dstats_tx_dropped(ovpn->dev, 1); kfree_skb(curr); -- 2.55.0 _______________________________________________ Openvpn-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/openvpn-devel
