common/parsing_helpers.h: add comment to parse_ethhdr()

netoptimizer · netoptimizer · commit 697250442364 · 2019-08-20T16:44:20.000+02:00
Signed-off-by: Jesper Dangaard Brouer &lt;brouer@redhat.com&gt;
diff --git a/common/parsing_helpers.h b/common/parsing_helpers.h
@@ -62,6 +62,11 @@ static __always_inline int proto_is_vlan(__u16 h_proto)
                   h_proto == bpf_htons(ETH_P_8021AD));
 }
 
+/* Notice, parse_ethhdr() will skip VLAN tags, by advancing nh->pos and returns
+ * next header EtherType, BUT the ethhdr pointer supplied still points to the
+ * Ethernet header. Thus, caller can look at eth->h_proto to see if this was a
+ * VLAN tagged packet.
+ */
 static __always_inline int parse_ethhdr(struct hdr_cursor *nh, void *data_end,
 					struct ethhdr **ethhdr)
 {
diff --git a/libbpf b/libbpf
@@ -1 +1 @@
-Subproject commit def5576b37a8170250f6a3e5f2b7cb817bdcbd60
+Subproject commit 910c475f09e5c269f441d7496c27dace30dc2335

Original file line number	Diff line number	Diff line change
`@@ -62,6 +62,11 @@ static __always_inline int proto_is_vlan(__u16 h_proto)`
`62`	`62`	`h_proto == bpf_htons(ETH_P_8021AD));`
`63`	`63`	`}`
`64`	`64`
	`65`	`+/* Notice, parse_ethhdr() will skip VLAN tags, by advancing nh->pos and returns`
	`66`	`+ * next header EtherType, BUT the ethhdr pointer supplied still points to the`
	`67`	`+ * Ethernet header. Thus, caller can look at eth->h_proto to see if this was a`
	`68`	`+ * VLAN tagged packet.`
	`69`	`+ */`
`65`	`70`	`static __always_inline int parse_ethhdr(struct hdr_cursor nh, void data_end,`
`66`	`71`	`struct ethhdr **ethhdr)`
`67`	`72`	`{`