selftests: xsk: Add frame_headroom test

Add a test for the frame_headroom feature that can be set on the
umem. The logic added validates that all offsets in all tests and
packets are valid, not just the ones that have a specifically
configured frame_headroom.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210922075613.12186-14-magnus.karlsson@gmail.com

diff --git a/tools/testing/selftests/bpf/xdpxceiver.c b/tools/testing/selftests/bpf/xdpxceiver.c
index fd620f8..6c7cf8a 100644 (file)
--- a/tools/testing/selftests/bpf/xdpxceiver.c
+++ b/tools/testing/selftests/bpf/xdpxceiver.c
@@ -514,8 +514,7 @@ static struct pkt_stream *pkt_stream_generate(struct xsk_umem_info *umem, u32 nb
 
        pkt_stream->nb_pkts = nb_pkts;
        for (i = 0; i < nb_pkts; i++) {
-               pkt_stream->pkts[i].addr = (i % umem->num_frames) * umem->frame_size +
-                       DEFAULT_OFFSET;
+               pkt_stream->pkts[i].addr = (i % umem->num_frames) * umem->frame_size;
                pkt_stream->pkts[i].len = pkt_len;
                pkt_stream->pkts[i].payload = i;
 
@@ -642,6 +641,25 @@ static void pkt_dump(void *pkt, u32 len)
        fprintf(stdout, "---------------------------------------\n");
 }
 
+static bool is_offset_correct(struct xsk_umem_info *umem, struct pkt_stream *pkt_stream, u64 addr,
+                             u64 pkt_stream_addr)
+{
+       u32 headroom = umem->unaligned_mode ? 0 : umem->frame_headroom;
+       u32 offset = addr % umem->frame_size, expected_offset = 0;
+
+       if (!pkt_stream->use_addr_for_fill)
+               pkt_stream_addr = 0;
+
+       expected_offset += (pkt_stream_addr + headroom + XDP_PACKET_HEADROOM) % umem->frame_size;
+
+       if (offset == expected_offset)
+               return true;
+
+       ksft_test_result_fail("ERROR: [%s] expected [%u], got [%u]\n", __func__, expected_offset,
+                             offset);
+       return false;
+}
+
 static bool is_pkt_valid(struct pkt *pkt, void *buffer, u64 addr, u32 len)
 {
        void *data = xsk_umem__get_data(buffer, addr);
@@ -724,6 +742,7 @@ static void receive_pkts(struct pkt_stream *pkt_stream, struct xsk_socket_info *
                         struct pollfd *fds)
 {
        struct pkt *pkt = pkt_stream_get_next_rx_pkt(pkt_stream);
+       struct xsk_umem_info *umem = xsk->umem;
        u32 idx_rx = 0, idx_fq = 0, rcvd, i;
        u32 total = 0;
        int ret;
@@ -731,7 +750,7 @@ static void receive_pkts(struct pkt_stream *pkt_stream, struct xsk_socket_info *
        while (pkt) {
                rcvd = xsk_ring_cons__peek(&xsk->rx, BATCH_SIZE, &idx_rx);
                if (!rcvd) {
-                       if (xsk_ring_prod__needs_wakeup(&xsk->umem->fq)) {
+                       if (xsk_ring_prod__needs_wakeup(&umem->fq)) {
                                ret = poll(fds, 1, POLL_TMOUT);
                                if (ret < 0)
                                        exit_with_error(-ret);
@@ -739,16 +758,16 @@ static void receive_pkts(struct pkt_stream *pkt_stream, struct xsk_socket_info *
                        continue;
                }
 
-               ret = xsk_ring_prod__reserve(&xsk->umem->fq, rcvd, &idx_fq);
+               ret = xsk_ring_prod__reserve(&umem->fq, rcvd, &idx_fq);
                while (ret != rcvd) {
                        if (ret < 0)
                                exit_with_error(-ret);
-                       if (xsk_ring_prod__needs_wakeup(&xsk->umem->fq)) {
+                       if (xsk_ring_prod__needs_wakeup(&umem->fq)) {
                                ret = poll(fds, 1, POLL_TMOUT);
                                if (ret < 0)
                                        exit_with_error(-ret);
                        }
-                       ret = xsk_ring_prod__reserve(&xsk->umem->fq, rcvd, &idx_fq);
+                       ret = xsk_ring_prod__reserve(&umem->fq, rcvd, &idx_fq);
                }
 
                for (i = 0; i < rcvd; i++) {
@@ -765,14 +784,17 @@ static void receive_pkts(struct pkt_stream *pkt_stream, struct xsk_socket_info *
 
                        orig = xsk_umem__extract_addr(addr);
                        addr = xsk_umem__add_offset_to_addr(addr);
-                       if (!is_pkt_valid(pkt, xsk->umem->buffer, addr, desc->len))
+
+                       if (!is_pkt_valid(pkt, umem->buffer, addr, desc->len))
+                               return;
+                       if (!is_offset_correct(umem, pkt_stream, addr, pkt->addr))
                                return;
 
-                       *xsk_ring_prod__fill_addr(&xsk->umem->fq, idx_fq++) = orig;
+                       *xsk_ring_prod__fill_addr(&umem->fq, idx_fq++) = orig;
                        pkt = pkt_stream_get_next_rx_pkt(pkt_stream);
                }
 
-               xsk_ring_prod__submit(&xsk->umem->fq, rcvd);
+               xsk_ring_prod__submit(&umem->fq, rcvd);
                xsk_ring_cons__release(&xsk->rx, rcvd);
 
                pthread_mutex_lock(&pacing_mutex);
@@ -1011,7 +1033,7 @@ static void xsk_populate_fill_ring(struct xsk_umem_info *umem, struct pkt_stream
                                break;
                        addr = pkt->addr;
                } else {
-                       addr = i * umem->frame_size + DEFAULT_OFFSET;
+                       addr = i * umem->frame_size;
                }
 
                *xsk_ring_prod__fill_addr(&umem->fq, idx++) = addr;
@@ -1134,6 +1156,13 @@ static void testapp_bpf_res(struct test_spec *test)
        testapp_validate_traffic(test);
 }
 
+static void testapp_headroom(struct test_spec *test)
+{
+       test_spec_set_name(test, "UMEM_HEADROOM");
+       test->ifobj_rx->umem->frame_headroom = UMEM_HEADROOM_TEST_SIZE;
+       testapp_validate_traffic(test);
+}
+
 static void testapp_stats(struct test_spec *test)
 {
        int i;
@@ -1346,6 +1375,9 @@ static void run_pkt_test(struct test_spec *test, enum test_mode mode, enum test_
                if (!testapp_unaligned(test))
                        return;
                break;
+       case TEST_TYPE_HEADROOM:
+               testapp_headroom(test);
+               break;
        default:
                break;
        }

diff --git a/tools/testing/selftests/bpf/xdpxceiver.h b/tools/testing/selftests/bpf/xdpxceiver.h
index d075192..2f705f4 100644 (file)
--- a/tools/testing/selftests/bpf/xdpxceiver.h
+++ b/tools/testing/selftests/bpf/xdpxceiver.h
@@ -41,7 +41,7 @@
 #define DEFAULT_UMEM_BUFFERS (DEFAULT_PKT_CNT / 4)
 #define UMEM_SIZE (DEFAULT_UMEM_BUFFERS * XSK_UMEM__DEFAULT_FRAME_SIZE)
 #define RX_FULL_RXQSIZE 32
-#define DEFAULT_OFFSET 256
+#define UMEM_HEADROOM_TEST_SIZE 128
 #define XSK_UMEM__INVALID_FRAME_SIZE (XSK_UMEM__DEFAULT_FRAME_SIZE + 1)
 
 #define print_verbose(x...) do { if (opt_verbose) ksft_print_msg(x); } while (0)
@@ -61,6 +61,7 @@ enum test_type {
        TEST_TYPE_ALIGNED_INV_DESC,
        TEST_TYPE_ALIGNED_INV_DESC_2K_FRAME,
        TEST_TYPE_UNALIGNED_INV_DESC,
+       TEST_TYPE_HEADROOM,
        TEST_TYPE_TEARDOWN,
        TEST_TYPE_BIDI,
        TEST_TYPE_STATS,