[RFC net-next v2] net: dsa: Remove indirect function call for flow dissection
From: Florian Fainelli
Date: Mon Dec 30 2019 - 14:21:51 EST
We only need "static" information to be given for DSA flow dissection,
so replace the expensive call to .flow_dissect() with an integer given
us the offset into the packet that we must de-reference to obtain the
protocol number. The overhead was alreayd available from the
dsa_device_ops structure so use that directly.
The presence of a flow_dissect callback used to indicate that the DSA
tagger supported returning that information,we now encode this with a
negative proto_off if the tagger does not support providing that
information.
Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
---
Changes in v2:
- update all taggers to indicate a valid/invalid protocol offset where
applicable
include/net/dsa.h | 3 +--
net/core/flow_dissector.c | 14 +++++++++-----
net/dsa/tag_brcm.c | 2 ++
net/dsa/tag_dsa.c | 10 +---------
net/dsa/tag_edsa.c | 10 +---------
net/dsa/tag_gswip.c | 1 +
net/dsa/tag_ksz.c | 3 +++
net/dsa/tag_lan9303.c | 1 +
net/dsa/tag_mtk.c | 11 +----------
net/dsa/tag_ocelot.c | 1 +
net/dsa/tag_qca.c | 11 +----------
net/dsa/tag_sja1105.c | 1 +
12 files changed, 23 insertions(+), 45 deletions(-)
diff --git a/include/net/dsa.h b/include/net/dsa.h
index da5578db228e..fc656cf3e3dd 100644
--- a/include/net/dsa.h
+++ b/include/net/dsa.h
@@ -72,14 +72,13 @@ struct dsa_device_ops {
struct sk_buff *(*xmit)(struct sk_buff *skb, struct net_device *dev);
struct sk_buff *(*rcv)(struct sk_buff *skb, struct net_device *dev,
struct packet_type *pt);
- int (*flow_dissect)(const struct sk_buff *skb, __be16 *proto,
- int *offset);
/* Used to determine which traffic should match the DSA filter in
* eth_type_trans, and which, if any, should bypass it and be processed
* as regular on the master net device.
*/
bool (*filter)(const struct sk_buff *skb, struct net_device *dev);
unsigned int overhead;
+ int proto_off;
const char *name;
enum dsa_tag_protocol proto;
};
diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c
index 2dbbb030fbed..942218943010 100644
--- a/net/core/flow_dissector.c
+++ b/net/core/flow_dissector.c
@@ -972,13 +972,17 @@ bool __skb_flow_dissect(const struct net *net,
if (unlikely(skb->dev && netdev_uses_dsa(skb->dev) &&
proto == htons(ETH_P_XDSA))) {
const struct dsa_device_ops *ops;
- int offset = 0;
+ unsigned int overhead;
+ int proto_off;
ops = skb->dev->dsa_ptr->tag_ops;
- if (ops->flow_dissect &&
- !ops->flow_dissect(skb, &proto, &offset)) {
- hlen -= offset;
- nhoff += offset;
+ overhead = ops->overhead;
+ proto_off = ops->proto_off;
+ if (likely(overhead && proto_off >= 0 &&
+ proto_off < skb->len)) {
+ hlen -= overhead;
+ nhoff += overhead;
+ proto = ((__be16 *)skb->data)[proto_off];
}
}
#endif
diff --git a/net/dsa/tag_brcm.c b/net/dsa/tag_brcm.c
index 9c3114179690..5b4c5bbba2cc 100644
--- a/net/dsa/tag_brcm.c
+++ b/net/dsa/tag_brcm.c
@@ -177,6 +177,7 @@ static const struct dsa_device_ops brcm_netdev_ops = {
.xmit = brcm_tag_xmit,
.rcv = brcm_tag_rcv,
.overhead = BRCM_TAG_LEN,
+ .proto_off = -1,
};
DSA_TAG_DRIVER(brcm_netdev_ops);
@@ -205,6 +206,7 @@ static const struct dsa_device_ops brcm_prepend_netdev_ops = {
.xmit = brcm_tag_xmit_prepend,
.rcv = brcm_tag_rcv_prepend,
.overhead = BRCM_TAG_LEN,
+ .proto_off = -1,
};
DSA_TAG_DRIVER(brcm_prepend_netdev_ops);
diff --git a/net/dsa/tag_dsa.c b/net/dsa/tag_dsa.c
index 7ddec9794477..4a970e959fef 100644
--- a/net/dsa/tag_dsa.c
+++ b/net/dsa/tag_dsa.c
@@ -142,21 +142,13 @@ static struct sk_buff *dsa_rcv(struct sk_buff *skb, struct net_device *dev,
return skb;
}
-static int dsa_tag_flow_dissect(const struct sk_buff *skb, __be16 *proto,
- int *offset)
-{
- *offset = 4;
- *proto = ((__be16 *)skb->data)[1];
- return 0;
-}
-
static const struct dsa_device_ops dsa_netdev_ops = {
.name = "dsa",
.proto = DSA_TAG_PROTO_DSA,
.xmit = dsa_xmit,
.rcv = dsa_rcv,
- .flow_dissect = dsa_tag_flow_dissect,
.overhead = DSA_HLEN,
+ .proto_off = 1,
};
MODULE_LICENSE("GPL");
diff --git a/net/dsa/tag_edsa.c b/net/dsa/tag_edsa.c
index e8eaa804ccb9..c7cb0df17287 100644
--- a/net/dsa/tag_edsa.c
+++ b/net/dsa/tag_edsa.c
@@ -161,21 +161,13 @@ static struct sk_buff *edsa_rcv(struct sk_buff *skb, struct net_device *dev,
return skb;
}
-static int edsa_tag_flow_dissect(const struct sk_buff *skb, __be16 *proto,
- int *offset)
-{
- *offset = 8;
- *proto = ((__be16 *)skb->data)[3];
- return 0;
-}
-
static const struct dsa_device_ops edsa_netdev_ops = {
.name = "edsa",
.proto = DSA_TAG_PROTO_EDSA,
.xmit = edsa_xmit,
.rcv = edsa_rcv,
- .flow_dissect = edsa_tag_flow_dissect,
.overhead = EDSA_HLEN,
+ .proto_off = 3,
};
MODULE_LICENSE("GPL");
diff --git a/net/dsa/tag_gswip.c b/net/dsa/tag_gswip.c
index b678160bbd66..646453c3ef44 100644
--- a/net/dsa/tag_gswip.c
+++ b/net/dsa/tag_gswip.c
@@ -109,6 +109,7 @@ static const struct dsa_device_ops gswip_netdev_ops = {
.xmit = gswip_tag_xmit,
.rcv = gswip_tag_rcv,
.overhead = GSWIP_RX_HEADER_LEN,
+ .proto_off = -1,
};
MODULE_LICENSE("GPL");
diff --git a/net/dsa/tag_ksz.c b/net/dsa/tag_ksz.c
index 90d055c4df9e..ab42d8ddeade 100644
--- a/net/dsa/tag_ksz.c
+++ b/net/dsa/tag_ksz.c
@@ -123,6 +123,7 @@ static const struct dsa_device_ops ksz8795_netdev_ops = {
.xmit = ksz8795_xmit,
.rcv = ksz8795_rcv,
.overhead = KSZ_INGRESS_TAG_LEN,
+ .proto_off = -1,
};
DSA_TAG_DRIVER(ksz8795_netdev_ops);
@@ -198,6 +199,7 @@ static const struct dsa_device_ops ksz9477_netdev_ops = {
.xmit = ksz9477_xmit,
.rcv = ksz9477_rcv,
.overhead = KSZ9477_INGRESS_TAG_LEN,
+ .proto_off = -1,
};
DSA_TAG_DRIVER(ksz9477_netdev_ops);
@@ -236,6 +238,7 @@ static const struct dsa_device_ops ksz9893_netdev_ops = {
.xmit = ksz9893_xmit,
.rcv = ksz9477_rcv,
.overhead = KSZ_INGRESS_TAG_LEN,
+ .proto_off = -1,
};
DSA_TAG_DRIVER(ksz9893_netdev_ops);
diff --git a/net/dsa/tag_lan9303.c b/net/dsa/tag_lan9303.c
index eb0e7a32e53d..709abf0ab6be 100644
--- a/net/dsa/tag_lan9303.c
+++ b/net/dsa/tag_lan9303.c
@@ -134,6 +134,7 @@ static const struct dsa_device_ops lan9303_netdev_ops = {
.xmit = lan9303_xmit,
.rcv = lan9303_rcv,
.overhead = LAN9303_TAG_LEN,
+ .proto_off = -1,
};
MODULE_LICENSE("GPL");
diff --git a/net/dsa/tag_mtk.c b/net/dsa/tag_mtk.c
index b5705cba8318..c96354f12317 100644
--- a/net/dsa/tag_mtk.c
+++ b/net/dsa/tag_mtk.c
@@ -89,22 +89,13 @@ static struct sk_buff *mtk_tag_rcv(struct sk_buff *skb, struct net_device *dev,
return skb;
}
-static int mtk_tag_flow_dissect(const struct sk_buff *skb, __be16 *proto,
- int *offset)
-{
- *offset = 4;
- *proto = ((__be16 *)skb->data)[1];
-
- return 0;
-}
-
static const struct dsa_device_ops mtk_netdev_ops = {
.name = "mtk",
.proto = DSA_TAG_PROTO_MTK,
.xmit = mtk_tag_xmit,
.rcv = mtk_tag_rcv,
- .flow_dissect = mtk_tag_flow_dissect,
.overhead = MTK_HDR_LEN,
+ .proto_off = 1,
};
MODULE_LICENSE("GPL");
diff --git a/net/dsa/tag_ocelot.c b/net/dsa/tag_ocelot.c
index 8e3e7283d430..d29e86c66853 100644
--- a/net/dsa/tag_ocelot.c
+++ b/net/dsa/tag_ocelot.c
@@ -233,6 +233,7 @@ static struct dsa_device_ops ocelot_netdev_ops = {
.xmit = ocelot_xmit,
.rcv = ocelot_rcv,
.overhead = OCELOT_TAG_LEN + OCELOT_LONG_PREFIX_LEN,
+ .proto_off = -1,
};
MODULE_LICENSE("GPL v2");
diff --git a/net/dsa/tag_qca.c b/net/dsa/tag_qca.c
index c95885215525..a88849d211f0 100644
--- a/net/dsa/tag_qca.c
+++ b/net/dsa/tag_qca.c
@@ -90,22 +90,13 @@ static struct sk_buff *qca_tag_rcv(struct sk_buff *skb, struct net_device *dev,
return skb;
}
-static int qca_tag_flow_dissect(const struct sk_buff *skb, __be16 *proto,
- int *offset)
-{
- *offset = QCA_HDR_LEN;
- *proto = ((__be16 *)skb->data)[0];
-
- return 0;
-}
-
static const struct dsa_device_ops qca_netdev_ops = {
.name = "qca",
.proto = DSA_TAG_PROTO_QCA,
.xmit = qca_tag_xmit,
.rcv = qca_tag_rcv,
- .flow_dissect = qca_tag_flow_dissect,
.overhead = QCA_HDR_LEN,
+ .proto_offset = 0,
};
MODULE_LICENSE("GPL");
diff --git a/net/dsa/tag_sja1105.c b/net/dsa/tag_sja1105.c
index 63ef2a14c934..626d3476c6af 100644
--- a/net/dsa/tag_sja1105.c
+++ b/net/dsa/tag_sja1105.c
@@ -300,6 +300,7 @@ static struct dsa_device_ops sja1105_netdev_ops = {
.rcv = sja1105_rcv,
.filter = sja1105_filter,
.overhead = VLAN_HLEN,
+ .proto_off = -1,
};
MODULE_LICENSE("GPL v2");
--
2.17.1