netdev - [PATCH net] geneve: initialize needed

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <c891d011ef98267cd72157a5b01c78347ada8d8e.1450883640.git.pabeni@redhat.com>
Date:	Wed, 23 Dec 2015 16:21:48 +0100
From:	Paolo Abeni <pabeni@...hat.com>
To:	netdev@...r.kernel.org
Cc:	"David S. Miller" <davem@...emloft.net>,
	Pravin B Shelar <pshelar@...ira.com>,
	Jiri Benc <jbenc@...hat.com>, Jesse Gross <jesse@...ira.com>,
	Hannes Frederic Sowa <hannes@...essinduktion.org>
Subject: [PATCH net] geneve: initialize needed_headroom

Currently the needed_headroom field for the geneve device is left
to the default value.

This patch set it to space required for basic geneve encapsulation,
so that we can avoid the skb head re-allocation on xmit.

This give a 6% speedup for unsegment traffic on geneve tunnel.

Signed-off-by: Paolo Abeni <pabeni@...hat.com>
Acked-by: Hannes Frederic Sowa <hannes@...essinduktion.org>
---
 drivers/net/geneve.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
index c2b79f5..bb3e6ed 100644
--- a/drivers/net/geneve.c
+++ b/drivers/net/geneve.c
@@ -1155,7 +1155,7 @@ static int geneve_configure(struct net *net, struct net_device *dev,
 	struct geneve_net *gn = net_generic(net, geneve_net_id);
 	struct geneve_dev *t, *geneve = netdev_priv(dev);
 	bool tun_collect_md, tun_on_same_port;
-	int err;
+	int err, encap_len;
 
 	if (!remote)
 		return -EINVAL;
@@ -1187,6 +1187,14 @@ static int geneve_configure(struct net *net, struct net_device *dev,
 	if (t)
 		return -EBUSY;
 
+	/* make enough headroom for basic scenario */
+	encap_len = GENEVE_BASE_HLEN + ETH_HLEN;
+	if (remote->sa.sa_family == AF_INET)
+		encap_len += sizeof(struct iphdr);
+	else
+		encap_len += sizeof(struct ipv6hdr);
+	dev->needed_headroom = encap_len;
+
 	if (metadata) {
 		if (tun_on_same_port)
 			return -EPERM;
-- 
1.8.3.1

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html