selftests/xsk: Make batch size variable

Convert the constant BATCH_SIZE into a variable named batch_size to allow
dynamic modification at runtime. This is required for the forthcoming
changes to support testing different hardware ring sizes.

While running these tests, a bug was identified when the batch size is
roughly the same as the NIC ring size. This has now been addressed by
Maciej's fix in commit 913eda2b08cc ("i40e: xsk: remove count_mask").

Signed-off-by: Tushar Vyavahare <tushar.vyavahare@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20240402114529.545475-3-tushar.vyavahare@intel.com

diff --git a/tools/testing/selftests/bpf/xskxceiver.c b/tools/testing/selftests/bpf/xskxceiver.c
index b1102ee13faa126bac9e86cdd9592721cc8a15b8..eaa102c8098b903b5a3cd8c449b083c028e20a2f 100644 (file)
--- a/tools/testing/selftests/bpf/xskxceiver.c
+++ b/tools/testing/selftests/bpf/xskxceiver.c
@@ -239,7 +239,7 @@ static void enable_busy_poll(struct xsk_socket_info *xsk)
                       (void *)&sock_opt, sizeof(sock_opt)) < 0)
                exit_with_error(errno);
 
-       sock_opt = BATCH_SIZE;
+       sock_opt = xsk->batch_size;
        if (setsockopt(xsk_socket__fd(xsk->xsk), SOL_SOCKET, SO_BUSY_POLL_BUDGET,
                       (void *)&sock_opt, sizeof(sock_opt)) < 0)
                exit_with_error(errno);
@@ -439,6 +439,7 @@ static void __test_spec_init(struct test_spec *test, struct ifobject *ifobj_tx,
                for (j = 0; j < MAX_SOCKETS; j++) {
                        memset(&ifobj->xsk_arr[j], 0, sizeof(ifobj->xsk_arr[j]));
                        ifobj->xsk_arr[j].rxqsize = XSK_RING_CONS__DEFAULT_NUM_DESCS;
+                       ifobj->xsk_arr[j].batch_size = DEFAULT_BATCH_SIZE;
                        if (i == 0)
                                ifobj->xsk_arr[j].pkt_stream = test->tx_pkt_stream_default;
                        else
@@ -1087,7 +1088,7 @@ static int __receive_pkts(struct test_spec *test, struct xsk_socket_info *xsk)
                        return TEST_CONTINUE;
        }
 
-       rcvd = xsk_ring_cons__peek(&xsk->rx, BATCH_SIZE, &idx_rx);
+       rcvd = xsk_ring_cons__peek(&xsk->rx, xsk->batch_size, &idx_rx);
        if (!rcvd)
                return TEST_CONTINUE;
 
@@ -1239,7 +1240,8 @@ static int __send_pkts(struct ifobject *ifobject, struct xsk_socket_info *xsk, b
 
        buffer_len = pkt_get_buffer_len(umem, pkt_stream->max_pkt_len);
        /* pkts_in_flight might be negative if many invalid packets are sent */
-       if (pkts_in_flight >= (int)((umem_size(umem) - BATCH_SIZE * buffer_len) / buffer_len)) {
+       if (pkts_in_flight >= (int)((umem_size(umem) - xsk->batch_size * buffer_len) /
+           buffer_len)) {
                ret = kick_tx(xsk);
                if (ret)
                        return TEST_FAILURE;
@@ -1249,7 +1251,7 @@ static int __send_pkts(struct ifobject *ifobject, struct xsk_socket_info *xsk, b
        fds.fd = xsk_socket__fd(xsk->xsk);
        fds.events = POLLOUT;
 
-       while (xsk_ring_prod__reserve(&xsk->tx, BATCH_SIZE, &idx) < BATCH_SIZE) {
+       while (xsk_ring_prod__reserve(&xsk->tx, xsk->batch_size, &idx) < xsk->batch_size) {
                if (use_poll) {
                        ret = poll(&fds, 1, POLL_TMOUT);
                        if (timeout) {
@@ -1269,10 +1271,10 @@ static int __send_pkts(struct ifobject *ifobject, struct xsk_socket_info *xsk, b
                        }
                }
 
-               complete_pkts(xsk, BATCH_SIZE);
+               complete_pkts(xsk, xsk->batch_size);
        }
 
-       for (i = 0; i < BATCH_SIZE; i++) {
+       for (i = 0; i < xsk->batch_size; i++) {
                struct pkt *pkt = pkt_stream_get_next_tx_pkt(pkt_stream);
                u32 nb_frags_left, nb_frags, bytes_written = 0;
 
@@ -1280,9 +1282,9 @@ static int __send_pkts(struct ifobject *ifobject, struct xsk_socket_info *xsk, b
                        break;
 
                nb_frags = pkt_nb_frags(umem->frame_size, pkt_stream, pkt);
-               if (nb_frags > BATCH_SIZE - i) {
+               if (nb_frags > xsk->batch_size - i) {
                        pkt_stream_cancel(pkt_stream);
-                       xsk_ring_prod__cancel(&xsk->tx, BATCH_SIZE - i);
+                       xsk_ring_prod__cancel(&xsk->tx, xsk->batch_size - i);
                        break;
                }
                nb_frags_left = nb_frags;
@@ -1370,7 +1372,7 @@ static int wait_for_tx_completion(struct xsk_socket_info *xsk)
                        return TEST_FAILURE;
                }
 
-               complete_pkts(xsk, BATCH_SIZE);
+               complete_pkts(xsk, xsk->batch_size);
        }
 
        return TEST_PASS;

diff --git a/tools/testing/selftests/bpf/xskxceiver.h b/tools/testing/selftests/bpf/xskxceiver.h
index f174df2d693f9cefe5897d1a94edb0c821c591f4..425304e52f3566913454dcb7c8d4599b625947e8 100644 (file)
--- a/tools/testing/selftests/bpf/xskxceiver.h
+++ b/tools/testing/selftests/bpf/xskxceiver.h
@@ -44,7 +44,7 @@
 #define MAX_ETH_JUMBO_SIZE 9000
 #define USLEEP_MAX 10000
 #define SOCK_RECONF_CTR 10
-#define BATCH_SIZE 64
+#define DEFAULT_BATCH_SIZE 64
 #define POLL_TMOUT 1000
 #define THREAD_TMOUT 3
 #define DEFAULT_PKT_CNT (4 * 1024)
@@ -91,6 +91,7 @@ struct xsk_socket_info {
        struct pkt_stream *pkt_stream;
        u32 outstanding_tx;
        u32 rxqsize;
+       u32 batch_size;
        u8 dst_mac[ETH_ALEN];
        u8 src_mac[ETH_ALEN];
 };