selftests: xsk: Generate packet directly in umem

Generate the packet directly in the umem instead of in a temporary
buffer that is copied out. Simplifies the code and improves
performance.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210825093722.10219-14-magnus.karlsson@gmail.com

diff --git a/tools/testing/selftests/bpf/xdpxceiver.c b/tools/testing/selftests/bpf/xdpxceiver.c
index 5e586a6..433c5c7 100644 (file)
--- a/tools/testing/selftests/bpf/xdpxceiver.c
+++ b/tools/testing/selftests/bpf/xdpxceiver.c
@@ -125,7 +125,7 @@ static void __exit_with_error(int error, const char *file, const char *func, int
                               test_type == TEST_TYPE_STATS ? "Stats" : "",\
                               test_type == TEST_TYPE_BPF_RES ? "BPF RES" : ""))
 
-static void *memset32_htonl(void *dest, u32 val, u32 size)
+static void memset32_htonl(void *dest, u32 val, u32 size)
 {
        u32 *ptr = (u32 *)dest;
        int i;
@@ -134,11 +134,6 @@ static void *memset32_htonl(void *dest, u32 val, u32 size)
 
        for (i = 0; i < (size & (~0x3)); i += 4)
                ptr[i >> 2] = val;
-
-       for (; i < size; i++)
-               ((char *)dest)[i] = ((char *)&val)[i & 3];
-
-       return dest;
 }
 
 /*
@@ -229,13 +224,13 @@ static void gen_ip_hdr(struct ifobject *ifobject, struct iphdr *ip_hdr)
        ip_hdr->check = 0;
 }
 
-static void gen_udp_hdr(struct generic_data *data, struct ifobject *ifobject,
+static void gen_udp_hdr(u32 payload, void *pkt, struct ifobject *ifobject,
                        struct udphdr *udp_hdr)
 {
        udp_hdr->source = htons(ifobject->src_port);
        udp_hdr->dest = htons(ifobject->dst_port);
        udp_hdr->len = htons(UDP_PKT_SIZE);
-       memset32_htonl(pkt_data + PKT_HDR_SIZE, htonl(data->seqnum), UDP_PKT_DATA_SIZE);
+       memset32_htonl(pkt + PKT_HDR_SIZE, payload, UDP_PKT_DATA_SIZE);
 }
 
 static void gen_udp_csum(struct udphdr *udp_hdr, struct iphdr *ip_hdr)
@@ -245,11 +240,6 @@ static void gen_udp_csum(struct udphdr *udp_hdr, struct iphdr *ip_hdr)
            udp_csum(ip_hdr->saddr, ip_hdr->daddr, UDP_PKT_SIZE, IPPROTO_UDP, (u16 *)udp_hdr);
 }
 
-static void gen_eth_frame(struct xsk_umem_info *umem, u64 addr)
-{
-       memcpy(xsk_umem__get_data(umem->buffer, addr), pkt_data, PKT_SIZE);
-}
-
 static void xsk_configure_umem(struct ifobject *data, void *buffer, u64 size, int idx)
 {
        struct xsk_umem_config cfg = {
@@ -427,6 +417,20 @@ static void parse_command_line(int argc, char **argv)
        }
 }
 
+static void pkt_generate(struct ifobject *ifobject, u32 pkt_nb, u64 addr)
+{
+       void *data = xsk_umem__get_data(ifobject->umem->buffer, addr);
+       struct udphdr *udp_hdr =
+               (struct udphdr *)(data + sizeof(struct ethhdr) + sizeof(struct iphdr));
+       struct iphdr *ip_hdr = (struct iphdr *)(data + sizeof(struct ethhdr));
+       struct ethhdr *eth_hdr = (struct ethhdr *)data;
+
+       gen_udp_hdr(pkt_nb, data, ifobject, udp_hdr);
+       gen_ip_hdr(ifobject, ip_hdr);
+       gen_udp_csum(udp_hdr, ip_hdr);
+       gen_eth_hdr(ifobject, eth_hdr);
+}
+
 static void pkt_dump(void *pkt, u32 len)
 {
        char s[INET_ADDRSTRLEN];
@@ -464,22 +468,23 @@ static void pkt_dump(void *pkt, u32 len)
        fprintf(stdout, "---------------------------------------\n");
 }
 
-static void pkt_validate(void *pkt)
+static void pkt_validate(void *buffer, u64 addr)
 {
-       struct iphdr *iphdr = (struct iphdr *)(pkt + sizeof(struct ethhdr));
+       void *data = xsk_umem__get_data(buffer, addr);
+       struct iphdr *iphdr = (struct iphdr *)(data + sizeof(struct ethhdr));
 
-       /*do not increment pktcounter if !(tos=0x9 and ipv4) */
        if (iphdr->version == IP_PKT_VER && iphdr->tos == IP_PKT_TOS) {
-               u32 payloadseqnum = *((uint32_t *)(pkt + PKT_HDR_SIZE));
+               u32 seqnum = ntohl(*((u32 *)(data + PKT_HDR_SIZE)));
+               u32 expected_seqnum = pkt_counter % num_frames;
 
                if (debug_pkt_dump && test_type != TEST_TYPE_STATS)
-                       pkt_dump(pkt, PKT_SIZE);
+                       pkt_dump(data, PKT_SIZE);
 
-               if (pkt_counter % num_frames != payloadseqnum) {
+               if (expected_seqnum != seqnum) {
                        ksft_test_result_fail
                                ("ERROR: [%s] expected seqnum [%d], got seqnum [%d]\n",
-                                       __func__, pkt_counter, payloadseqnum);
-                       ksft_exit_xfail();
+                                       __func__, expected_seqnum, seqnum);
+                       sigvar = 1;
                }
 
                if (++pkt_counter == opt_pkt_count)
@@ -488,6 +493,7 @@ static void pkt_validate(void *pkt)
                ksft_print_msg("Invalid frame received: ");
                ksft_print_msg("[IP_PKT_VER: %02X], [IP_PKT_TOS: %02X]\n", iphdr->version,
                               iphdr->tos);
+               sigvar = 1;
        }
 }
 
@@ -555,7 +561,7 @@ static void rx_pkt(struct xsk_socket_info *xsk, struct pollfd *fds)
                orig = xsk_umem__extract_addr(addr);
 
                addr = xsk_umem__add_offset_to_addr(addr);
-               pkt_validate(xsk_umem__get_data(xsk->umem->buffer, addr));
+               pkt_validate(xsk->umem->buffer, addr);
 
                *xsk_ring_prod__fill_addr(&xsk->umem->fq, idx_fq++) = orig;
        }
@@ -564,8 +570,9 @@ static void rx_pkt(struct xsk_socket_info *xsk, struct pollfd *fds)
        xsk_ring_cons__release(&xsk->rx, rcvd);
 }
 
-static void tx_only(struct xsk_socket_info *xsk, u32 *frameptr, int batch_size)
+static void tx_only(struct ifobject *ifobject, u32 *frameptr, int batch_size)
 {
+       struct xsk_socket_info *xsk = ifobject->xsk;
        u32 idx = 0;
        unsigned int i;
        bool tx_invalid_test = stat_test_type == STAT_TEST_TX_INVALID;
@@ -579,6 +586,7 @@ static void tx_only(struct xsk_socket_info *xsk, u32 *frameptr, int batch_size)
 
                tx_desc->addr = (*frameptr + i) << XSK_UMEM__DEFAULT_FRAME_SHIFT;
                tx_desc->len = len;
+               pkt_generate(ifobject, *frameptr + i, tx_desc->addr);
        }
 
        xsk_ring_prod__submit(&xsk->tx, batch_size);
@@ -635,7 +643,7 @@ static void tx_only_all(struct ifobject *ifobject)
                                continue;
                }
 
-               tx_only(ifobject->xsk, &frame_nb, batch_size);
+               tx_only(ifobject, &frame_nb, batch_size);
                pkt_cnt += batch_size;
                usleep(10);
        }
@@ -768,26 +776,12 @@ static void testapp_cleanup_xsk_res(struct ifobject *ifobj)
 
 static void *worker_testapp_validate_tx(void *arg)
 {
-       struct udphdr *udp_hdr =
-           (struct udphdr *)(pkt_data + sizeof(struct ethhdr) + sizeof(struct iphdr));
-       struct iphdr *ip_hdr = (struct iphdr *)(pkt_data + sizeof(struct ethhdr));
-       struct ethhdr *eth_hdr = (struct ethhdr *)pkt_data;
        struct ifobject *ifobject = (struct ifobject *)arg;
-       struct generic_data data;
        void *bufs = NULL;
 
        if (!second_step)
                thread_common_ops(ifobject, bufs);
 
-       for (int i = 0; i < num_frames; i++) {
-               data.seqnum = i;
-               gen_udp_hdr(&data, ifobject, udp_hdr);
-               gen_ip_hdr(ifobject, ip_hdr);
-               gen_udp_csum(udp_hdr, ip_hdr);
-               gen_eth_hdr(ifobject, eth_hdr);
-               gen_eth_frame(ifobject->umem, i * XSK_UMEM__DEFAULT_FRAME_SIZE);
-       }
-
        print_verbose("Sending %d packets on interface %s\n", opt_pkt_count, ifobject->ifname);
        tx_only_all(ifobject);
 

diff --git a/tools/testing/selftests/bpf/xdpxceiver.h b/tools/testing/selftests/bpf/xdpxceiver.h
index 316c356..7670df7 100644 (file)
--- a/tools/testing/selftests/bpf/xdpxceiver.h
+++ b/tools/testing/selftests/bpf/xdpxceiver.h
@@ -79,7 +79,6 @@ static u8 opt_verbose;
 
 static u32 xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
 static u32 xdp_bind_flags = XDP_USE_NEED_WAKEUP | XDP_COPY;
-static u8 pkt_data[XSK_UMEM__DEFAULT_FRAME_SIZE];
 static u32 pkt_counter;
 static int sigvar;
 static int stat_test_type;
@@ -108,10 +107,6 @@ struct flow_vector {
        } vector;
 };
 
-struct generic_data {
-       u32 seqnum;
-};
-
 struct ifobject {
        char ifname[MAX_INTERFACE_NAME_CHARS];
        char nsname[MAX_INTERFACES_NAMESPACE_CHARS];