[Openvpn-devel,RFC,net-next,7/9] ovpn: prefetch GSO segments before in-place encryption
| Message ID | 382879c187b1acca65198c467d1263266243ea50.1789485693.git.ralf@mandelbit.com |
|---|---|
| State | Superseded |
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From: Ralf Lici <ralf@mandelbit.com>
To: openvpn-devel@lists.sourceforge.net
Date: Tue, 15 Sep 2026 17:23:55 +0200
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Content preview: 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 n [...]
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Subject: [Openvpn-devel] [RFC ovpn net-next 7/9] ovpn: prefetch GSO segments
before in-place encryption
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| Series |
ovpn: preserve GSO and GRO batching
|
|
Commit Message
Ralf Lici
Sept. 15, 2026, 3:23 p.m. UTC
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 <ralf@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);