On Thu, Jul 03, 2025 at 10:17:12PM +0800, Jason Xing wrote: > From: Jason Xing <kernelxing@xxxxxxxxxxx> > > The subtest sends 33 packets at one time on purpose to see if xsk > exitting __xsk_generic_xmit() updates the global consumer of tx queue > when reaching the max loop (max_tx_budget, 32 by default). The number 33 > can avoid xskq_cons_peek_desc() updates the consumer when it's about to > quit sending, to accurately check if the issue that the first patch > resolves remains. The new case will not check this issue in zero copy > mode. > > Signed-off-by: Jason Xing <kernelxing@xxxxxxxxxxx> Acked-by: Maciej Fijalkowski <maciej.fijalkowski@xxxxxxxxx> > --- > v6 > Link: https://lore.kernel.org/all/20250702112815.50746-1-kerneljasonxing@xxxxxxxxx/ > 1. filter out and skip TEST_MODE_ZC test. > > v5 > Link: https://lore.kernel.org/all/20250627085745.53173-1-kerneljasonxing@xxxxxxxxx/ > 1. use the initial approach to add a new testcase > 2. add a new flag 'check_consumer' to see if the check is needed > --- > tools/testing/selftests/bpf/xskxceiver.c | 56 +++++++++++++++++++++++- > tools/testing/selftests/bpf/xskxceiver.h | 1 + > 2 files changed, 56 insertions(+), 1 deletion(-) > > diff --git a/tools/testing/selftests/bpf/xskxceiver.c b/tools/testing/selftests/bpf/xskxceiver.c > index 0ced4026ee44..a29de0713f19 100644 > --- a/tools/testing/selftests/bpf/xskxceiver.c > +++ b/tools/testing/selftests/bpf/xskxceiver.c > @@ -109,6 +109,8 @@ > > #include <network_helpers.h> > > +#define MAX_TX_BUDGET_DEFAULT 32 > + > static bool opt_verbose; > static bool opt_print_tests; > static enum test_mode opt_mode = TEST_MODE_ALL; > @@ -1091,11 +1093,45 @@ static bool is_pkt_valid(struct pkt *pkt, void *buffer, u64 addr, u32 len) > return true; > } > > +static u32 load_value(u32 *counter) > +{ > + return __atomic_load_n(counter, __ATOMIC_ACQUIRE); > +} > + > +static bool kick_tx_with_check(struct xsk_socket_info *xsk, int *ret) > +{ > + u32 max_budget = MAX_TX_BUDGET_DEFAULT; > + u32 cons, ready_to_send; > + int delta; > + > + cons = load_value(xsk->tx.consumer); > + ready_to_send = load_value(xsk->tx.producer) - cons; > + *ret = sendto(xsk_socket__fd(xsk->xsk), NULL, 0, MSG_DONTWAIT, NULL, 0); > + > + delta = load_value(xsk->tx.consumer) - cons; > + /* By default, xsk should consume exact @max_budget descs at one > + * send in this case where hitting the max budget limit in while > + * loop is triggered in __xsk_generic_xmit(). Please make sure that > + * the number of descs to be sent is larger than @max_budget, or > + * else the tx.consumer will be updated in xskq_cons_peek_desc() > + * in time which hides the issue we try to verify. > + */ > + if (ready_to_send > max_budget && delta != max_budget) > + return false; > + > + return true; > +} > + > static int kick_tx(struct xsk_socket_info *xsk) > { > int ret; > > - ret = sendto(xsk_socket__fd(xsk->xsk), NULL, 0, MSG_DONTWAIT, NULL, 0); > + if (xsk->check_consumer) { > + if (!kick_tx_with_check(xsk, &ret)) > + return TEST_FAILURE; > + } else { > + ret = sendto(xsk_socket__fd(xsk->xsk), NULL, 0, MSG_DONTWAIT, NULL, 0); > + } > if (ret >= 0) > return TEST_PASS; > if (errno == ENOBUFS || errno == EAGAIN || errno == EBUSY || errno == ENETDOWN) { > @@ -2613,6 +2649,23 @@ static int testapp_adjust_tail_grow_mb(struct test_spec *test) > XSK_UMEM__LARGE_FRAME_SIZE * 2); > } > > +static int testapp_tx_queue_consumer(struct test_spec *test) > +{ > + int nr_packets; > + > + if (test->mode == TEST_MODE_ZC) { > + ksft_test_result_skip("Can not run TX_QUEUE_CONSUMER test for ZC mode\n"); > + return TEST_SKIP; > + } > + > + nr_packets = MAX_TX_BUDGET_DEFAULT + 1; > + pkt_stream_replace(test, nr_packets, MIN_PKT_SIZE); > + test->ifobj_tx->xsk->batch_size = nr_packets; > + test->ifobj_tx->xsk->check_consumer = true; > + > + return testapp_validate_traffic(test); > +} > + > static void run_pkt_test(struct test_spec *test) > { > int ret; > @@ -2723,6 +2776,7 @@ static const struct test_spec tests[] = { > {.name = "XDP_ADJUST_TAIL_SHRINK_MULTI_BUFF", .test_func = testapp_adjust_tail_shrink_mb}, > {.name = "XDP_ADJUST_TAIL_GROW", .test_func = testapp_adjust_tail_grow}, > {.name = "XDP_ADJUST_TAIL_GROW_MULTI_BUFF", .test_func = testapp_adjust_tail_grow_mb}, > + {.name = "TX_QUEUE_CONSUMER", .test_func = testapp_tx_queue_consumer}, > }; > > static void print_tests(void) > diff --git a/tools/testing/selftests/bpf/xskxceiver.h b/tools/testing/selftests/bpf/xskxceiver.h > index 67fc44b2813b..4df3a5d329ac 100644 > --- a/tools/testing/selftests/bpf/xskxceiver.h > +++ b/tools/testing/selftests/bpf/xskxceiver.h > @@ -95,6 +95,7 @@ struct xsk_socket_info { > u32 batch_size; > u8 dst_mac[ETH_ALEN]; > u8 src_mac[ETH_ALEN]; > + bool check_consumer; > }; > > struct pkt { > -- > 2.41.3 >
