From 8c816dc54d3b047ad6943ff6f3aa941cb529e947 Mon Sep 17 00:00:00 2001 From: Joyce Kong Date: Mon, 19 Jul 2021 22:51:24 -0500 Subject: [PATCH] test/service: use compiler atomics for lock sync Convert rte_atomic usages to compiler atomic built-ins for lock sync in service_cores testcases. Signed-off-by: Joyce Kong Reviewed-by: Ruifeng Wang Acked-by: Stephen Hemminger --- app/test/test_service_cores.c | 36 +++++++++++++++++++---------------- 1 file changed, 20 insertions(+), 16 deletions(-) diff --git a/app/test/test_service_cores.c b/app/test/test_service_cores.c index 37d7172d53..ece104054e 100644 --- a/app/test/test_service_cores.c +++ b/app/test/test_service_cores.c @@ -53,18 +53,20 @@ static int32_t dummy_cb(void *args) static int32_t dummy_mt_unsafe_cb(void *args) { /* before running test, the initialization has set pass_test to 1. - * If the cmpset in service-cores is working correctly, the code here + * If the CAS in service-cores is working correctly, the code here * should never fail to take the lock. If the lock *is* taken, fail the * test, because two threads are concurrently in a non-MT safe callback. */ uint32_t *test_params = args; - uint32_t *atomic_lock = &test_params[0]; + uint32_t *lock = &test_params[0]; uint32_t *pass_test = &test_params[1]; - int lock_taken = rte_atomic32_cmpset(atomic_lock, 0, 1); + uint32_t exp = 0; + int lock_taken = __atomic_compare_exchange_n(lock, &exp, 1, 0, + __ATOMIC_RELAXED, __ATOMIC_RELAXED); if (lock_taken) { /* delay with the lock held */ rte_delay_ms(250); - rte_atomic32_clear((rte_atomic32_t *)atomic_lock); + __atomic_store_n(lock, 0, __ATOMIC_RELAXED); } else { /* 2nd thread will fail to take lock, so set pass flag */ *pass_test = 0; @@ -83,13 +85,15 @@ static int32_t dummy_mt_safe_cb(void *args) * that 2 threads are running the callback at the same time: MT safe */ uint32_t *test_params = args; - uint32_t *atomic_lock = &test_params[0]; + uint32_t *lock = &test_params[0]; uint32_t *pass_test = &test_params[1]; - int lock_taken = rte_atomic32_cmpset(atomic_lock, 0, 1); + uint32_t exp = 0; + int lock_taken = __atomic_compare_exchange_n(lock, &exp, 1, 0, + __ATOMIC_RELAXED, __ATOMIC_RELAXED); if (lock_taken) { /* delay with the lock held */ rte_delay_ms(250); - rte_atomic32_clear((rte_atomic32_t *)atomic_lock); + __atomic_store_n(lock, 0, __ATOMIC_RELAXED); } else { /* 2nd thread will fail to take lock, so set pass flag */ *pass_test = 1; @@ -622,9 +626,9 @@ service_threaded_test(int mt_safe) TEST_ASSERT_EQUAL(0, rte_service_lcore_add(slcore_2), "mt safe lcore add fail"); - /* Use atomic locks to verify that two threads are in the same function - * at the same time. These are passed to the unit tests through the - * callback userdata parameter + /* Use locks to verify that two threads are in the same function + * at the same time. These are passed to the unit tests through + * the callback userdata parameter. */ uint32_t test_params[2]; memset(test_params, 0, sizeof(uint32_t) * 2); @@ -713,7 +717,7 @@ service_mt_safe_poll(void) } /* tests a NON mt safe service with two cores, the callback is serialized - * using the atomic cmpset. + * using the CAS. */ static int service_mt_unsafe_poll(void) @@ -735,17 +739,17 @@ delay_as_a_mt_safe_service(void *args) RTE_SET_USED(args); uint32_t *params = args; - /* retrieve done flag and atomic lock to inc/dec */ + /* retrieve done flag and lock to add/sub */ uint32_t *done = ¶ms[0]; - rte_atomic32_t *lock = (rte_atomic32_t *)¶ms[1]; + uint32_t *lock = ¶ms[1]; while (!*done) { - rte_atomic32_inc(lock); + __atomic_add_fetch(lock, 1, __ATOMIC_RELAXED); rte_delay_us(500); - if (rte_atomic32_read(lock) > 1) + if (__atomic_load_n(lock, __ATOMIC_RELAXED) > 1) /* pass: second core has simultaneously incremented */ *done = 1; - rte_atomic32_dec(lock); + __atomic_sub_fetch(lock, 1, __ATOMIC_RELAXED); } return 0;