selftests: xsk: Simplify frame traversal in dumping thread

Store offsets to each layer in a separate variables rather than compute
them every single time.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210329224316.17793-6-maciej.fijalkowski@intel.com

diff --git a/tools/testing/selftests/bpf/xdpxceiver.c b/tools/testing/selftests/bpf/xdpxceiver.c
index 77880ab..ae2f7d7 100644 (file)
--- a/tools/testing/selftests/bpf/xdpxceiver.c
+++ b/tools/testing/selftests/bpf/xdpxceiver.c
@@ -658,45 +658,40 @@ static void tx_only_all(struct ifobject *ifobject)
 
 static void worker_pkt_dump(void)
 {
-       struct in_addr ipaddr;
+       struct ethhdr *ethhdr;
+       struct iphdr *iphdr;
+       struct udphdr *udphdr;
+       char s[128];
+       int payload;
+       void *ptr;
 
        fprintf(stdout, "---------------------------------------\n");
        for (int iter = 0; iter < num_frames - 1; iter++) {
+               ptr = pkt_buf[iter]->payload;
+               ethhdr = ptr;
+               iphdr = ptr + sizeof(*ethhdr);
+               udphdr = ptr + sizeof(*ethhdr) + sizeof(*iphdr);
+
                /*extract L2 frame */
                fprintf(stdout, "DEBUG>> L2: dst mac: ");
                for (int i = 0; i < ETH_ALEN; i++)
-                       fprintf(stdout, "%02X", ((struct ethhdr *)
-                                                pkt_buf[iter]->payload)->h_dest[i]);
+                       fprintf(stdout, "%02X", ethhdr->h_dest[i]);
 
                fprintf(stdout, "\nDEBUG>> L2: src mac: ");
                for (int i = 0; i < ETH_ALEN; i++)
-                       fprintf(stdout, "%02X", ((struct ethhdr *)
-                                                pkt_buf[iter]->payload)->h_source[i]);
+                       fprintf(stdout, "%02X", ethhdr->h_source[i]);
 
                /*extract L3 frame */
-               fprintf(stdout, "\nDEBUG>> L3: ip_hdr->ihl: %02X\n",
-                       ((struct iphdr *)(pkt_buf[iter]->payload + sizeof(struct ethhdr)))->ihl);
-
-               ipaddr.s_addr =
-                   ((struct iphdr *)(pkt_buf[iter]->payload + sizeof(struct ethhdr)))->saddr;
-               fprintf(stdout, "DEBUG>> L3: ip_hdr->saddr: %s\n", inet_ntoa(ipaddr));
-
-               ipaddr.s_addr =
-                   ((struct iphdr *)(pkt_buf[iter]->payload + sizeof(struct ethhdr)))->daddr;
-               fprintf(stdout, "DEBUG>> L3: ip_hdr->daddr: %s\n", inet_ntoa(ipaddr));
-
+               fprintf(stdout, "\nDEBUG>> L3: ip_hdr->ihl: %02X\n", iphdr->ihl);
+               fprintf(stdout, "DEBUG>> L3: ip_hdr->saddr: %s\n",
+                       inet_ntop(AF_INET, &iphdr->saddr, s, sizeof(s)));
+               fprintf(stdout, "DEBUG>> L3: ip_hdr->daddr: %s\n",
+                       inet_ntop(AF_INET, &iphdr->daddr, s, sizeof(s)));
                /*extract L4 frame */
-               fprintf(stdout, "DEBUG>> L4: udp_hdr->src: %d\n",
-                       ntohs(((struct udphdr *)(pkt_buf[iter]->payload +
-                                                sizeof(struct ethhdr) +
-                                                sizeof(struct iphdr)))->source));
-
-               fprintf(stdout, "DEBUG>> L4: udp_hdr->dst: %d\n",
-                       ntohs(((struct udphdr *)(pkt_buf[iter]->payload +
-                                                sizeof(struct ethhdr) +
-                                                sizeof(struct iphdr)))->dest));
+               fprintf(stdout, "DEBUG>> L4: udp_hdr->src: %d\n", ntohs(udphdr->source));
+               fprintf(stdout, "DEBUG>> L4: udp_hdr->dst: %d\n", ntohs(udphdr->dest));
                /*extract L5 frame */
-               int payload = *((uint32_t *)(pkt_buf[iter]->payload + PKT_HDR_SIZE));
+               payload = *((uint32_t *)(ptr + PKT_HDR_SIZE));
 
                if (payload == EOT) {
                        print_verbose("End-of-transmission frame received\n");