On 13/06/2023 11.18, baomingtong001@xxxxxxxxxx wrote:
Fix the following coccicheck warning:
samples/bpf/xdp1_kern.c:50: Unneeded variable: "rc".
Signed-off-by: Mingtong Bao <baomingtong001@xxxxxxxxxx>
---
samples/bpf/xdp1_kern.c | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)
diff --git a/samples/bpf/xdp1_kern.c b/samples/bpf/xdp1_kern.c
index d91f27cbcfa9..d426df4a9d6b 100644
--- a/samples/bpf/xdp1_kern.c
+++ b/samples/bpf/xdp1_kern.c
@@ -47,18 +47,17 @@ int xdp_prog1(struct xdp_md *ctx)
void *data_end = &pkt[XDPBUFSIZE-1];
void *data = pkt;
struct ethhdr *eth = data;
- int rc = XDP_DROP;
long *value;
u16 h_proto;
u64 nh_off;
u32 ipproto;
if (bpf_xdp_load_bytes(ctx, 0, pkt, sizeof(pkt)))
- return rc;
+ return XDP_DROP;
IMHO for these error cases, we should return XDP_ABORTED instead.
This will make is easier to debug, e.g. with xdpdump[1] or xdp-monitor[2].
Reminder that drivers (usually) have a tracepoint for XDP_ABORTED
(code see trace_xdp_exception).
[1] https://github.com/xdp-project/xdp-tools/tree/master/xdp-dump
[2] https://github.com/xdp-project/xdp-tools/tree/master/xdp-monitor
nh_off = sizeof(*eth);
if (data + nh_off > data_end)
- return rc;
+ return XDP_DROP;
h_proto = eth->h_proto;
@@ -69,7 +68,7 @@ int xdp_prog1(struct xdp_md *ctx)
vhdr = data + nh_off;
nh_off += sizeof(struct vlan_hdr);
if (data + nh_off > data_end)
- return rc;
+ return XDP_DROP;
Use XDP_ABORTED
h_proto = vhdr->h_vlan_encapsulated_proto;
}
/* Handle double VLAN tagged packet */
@@ -79,7 +78,7 @@ int xdp_prog1(struct xdp_md *ctx)
vhdr = data + nh_off;
nh_off += sizeof(struct vlan_hdr);
if (data + nh_off > data_end)
- return rc;
+ return XDP_DROP;
Use XDP_ABORTED
h_proto = vhdr->h_vlan_encapsulated_proto;
}
@@ -94,7 +93,7 @@ int xdp_prog1(struct xdp_md *ctx)
if (value)
*value += 1;
- return rc;
+ return XDP_DROP;
This is correct. Here use XDP_DROP.
}
char _license[] SEC("license") = "GPL";
