From 0464b1ed07677f869005bde3fade1580b48de67e Mon Sep 17 00:00:00 2001 From: Maciej Fijalkowski Date: Tue, 30 Mar 2021 00:43:11 +0200 Subject: [PATCH] selftests: xsk: Remove sync_mutex_tx and atomic var Although thread_common_ops() are called in both Tx and Rx threads, testapp_validate() will not spawn Tx thread until Rx thread signals that it has finished its initialization via condition variable. Therefore, locking in thread_common_ops is not needed and furthermore Tx thread does not have to spin on atomic variable. Note that this simplification wouldn't be possible if there would still be a common worker thread. Signed-off-by: Maciej Fijalkowski Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20210329224316.17793-13-maciej.fijalkowski@intel.com --- tools/testing/selftests/bpf/xdpxceiver.c | 31 +++++++------------------------ tools/testing/selftests/bpf/xdpxceiver.h | 2 -- 2 files changed, 7 insertions(+), 26 deletions(-) diff --git a/tools/testing/selftests/bpf/xdpxceiver.c b/tools/testing/selftests/bpf/xdpxceiver.c index c0ebca8f55f8..35e14ad8097e 100644 --- a/tools/testing/selftests/bpf/xdpxceiver.c +++ b/tools/testing/selftests/bpf/xdpxceiver.c @@ -121,17 +121,15 @@ static void __exit_with_error(int error, const char *file, const char *func, int test_type == TEST_TYPE_BIDI ? "Bi-directional Sockets" : "",\ test_type == TEST_TYPE_STATS ? "Stats" : "")) -static void pthread_init_mutex(void) +static void init_sync_resources(void) { pthread_mutex_init(&sync_mutex, NULL); - pthread_mutex_init(&sync_mutex_tx, NULL); pthread_cond_init(&signal_rx_condition, NULL); } -static void pthread_destroy_mutex(void) +static void destroy_sync_resources(void) { pthread_mutex_destroy(&sync_mutex); - pthread_mutex_destroy(&sync_mutex_tx); pthread_cond_destroy(&signal_rx_condition); } @@ -752,7 +750,7 @@ static void worker_pkt_validate(void) } } -static void thread_common_ops(struct ifobject *ifobject, void *bufs, pthread_mutex_t *mutexptr) +static void thread_common_ops(struct ifobject *ifobject, void *bufs) { int ctr = 0; int ret; @@ -771,22 +769,13 @@ static void thread_common_ops(struct ifobject *ifobject, void *bufs, pthread_mut /* Retry Create Socket if it fails as xsk_socket__create() * is asynchronous - * - * Essential to lock Mutex here to prevent Tx thread from - * entering before Rx and causing a deadlock */ - pthread_mutex_lock(mutexptr); while (ret && ctr < SOCK_RECONF_CTR) { - if (ifobject->fv.vector == rx) - atomic_store(&spinning_rx, 1); xsk_configure_umem(ifobject, bufs, num_frames * XSK_UMEM__DEFAULT_FRAME_SIZE); ret = xsk_configure_socket(ifobject); usleep(USLEEP_MAX); ctr++; } - if (ifobject->fv.vector == rx) - atomic_store(&spinning_rx, 0); - pthread_mutex_unlock(mutexptr); if (ctr >= SOCK_RECONF_CTR) exit_with_error(ret); @@ -803,16 +792,10 @@ static void *worker_testapp_validate_tx(void *arg) struct ethhdr *eth_hdr = (struct ethhdr *)pkt_data; struct ifobject *ifobject = (struct ifobject *)arg; struct generic_data data; - int spinningrxctr = 0; void *bufs = NULL; if (!bidi_pass) - thread_common_ops(ifobject, bufs, &sync_mutex_tx); - - while (atomic_load(&spinning_rx) && spinningrxctr < SOCK_RECONF_CTR) { - spinningrxctr++; - usleep(USLEEP_MAX); - } + thread_common_ops(ifobject, bufs); for (int i = 0; i < num_frames; i++) { /*send EOT frame */ @@ -845,7 +828,7 @@ static void *worker_testapp_validate_rx(void *arg) void *bufs = NULL; if (!bidi_pass) - thread_common_ops(ifobject, bufs, &sync_mutex_tx); + thread_common_ops(ifobject, bufs); if (stat_test_type != STAT_TEST_RX_FILL_EMPTY) xsk_populate_fill_ring(ifobject->umem); @@ -1103,7 +1086,7 @@ int main(int argc, char **argv) ksft_set_plan(TEST_MODE_MAX * TEST_TYPE_MAX); - pthread_init_mutex(); + init_sync_resources(); for (i = 0; i < TEST_MODE_MAX; i++) { for (j = 0; j < TEST_TYPE_MAX; j++) @@ -1116,7 +1099,7 @@ int main(int argc, char **argv) free(ifdict[i]); } - pthread_destroy_mutex(); + destroy_sync_resources(); ksft_exit_pass(); diff --git a/tools/testing/selftests/bpf/xdpxceiver.h b/tools/testing/selftests/bpf/xdpxceiver.h index 3945746900af..e304229d8a4c 100644 --- a/tools/testing/selftests/bpf/xdpxceiver.h +++ b/tools/testing/selftests/bpf/xdpxceiver.h @@ -146,9 +146,7 @@ static struct ifobject *ifdict_rx; static struct ifobject *ifdict_tx; /*threads*/ -atomic_int spinning_rx; pthread_mutex_t sync_mutex; -pthread_mutex_t sync_mutex_tx; pthread_cond_t signal_rx_condition; pthread_t t0, t1; pthread_attr_t attr; -- 2.11.0