[PATCH v2] test/bitops: check worker lcore availability

[David Marchand <david.marchand@redhat.com>]

Coverity is not able to understand that having 2 lcores means that
rte_get_next_lcore(-1, 0, 1) can't return RTE_MAX_LCORE.
Add a check.

Coverity issue: 445382, 445383, 445384, 445387, 445389, 445391
Fixes: 35326b61aecb ("bitops: add atomic bit operations in new API")

Signed-off-by: David Marchand <david.marchand@redhat.com>
---
Changes since v2:
- added a helper,
- prefer RTE_VERIFY(),

Note: 
- a better fix would be to check lcore id validity in the EAL launch API,
  but it requires inspecting all functions and it could result in some
  API change, so sending this as a simple fix for now,

---
 app/test/test_bitops.c | 17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/app/test/test_bitops.c b/app/test/test_bitops.c
index 681e984037..78a7df6bb1 100644
--- a/app/test/test_bitops.c
+++ b/app/test/test_bitops.c
@@ -13,6 +13,17 @@
 #include <rte_random.h>
 #include "test.h"
 
+static unsigned int
+get_worker_lcore(void)
+{
+	unsigned int lcore_id = rte_get_next_lcore(-1, 1, 0);
+
+	/* avoid checkers (like Coverity) false positives */
+	RTE_VERIFY(lcore_id < RTE_MAX_LCORE);
+
+	return lcore_id;
+}
+
 #define GEN_TEST_BIT_ACCESS(test_name, set_fun, clear_fun, assign_fun, flip_fun, test_fun, size, \
 		mod) \
 static int \
@@ -158,7 +169,7 @@ test_bit_atomic_parallel_assign ## size(void) \
 		printf("Need multiple cores to run parallel test.\n"); \
 		return TEST_SKIPPED; \
 	} \
-	worker_lcore_id = rte_get_next_lcore(-1, 1, 0); \
+	worker_lcore_id = get_worker_lcore(); \
 	lmain.bit = rte_rand_max(size); \
 	do { \
 		lworker.bit = rte_rand_max(size); \
@@ -217,7 +228,7 @@ test_bit_atomic_parallel_test_and_modify ## size(void) \
 		printf("Need multiple cores to run parallel test.\n"); \
 		return TEST_SKIPPED; \
 	} \
-	worker_lcore_id = rte_get_next_lcore(-1, 1, 0); \
+	worker_lcore_id = get_worker_lcore(); \
 	int rc = rte_eal_remote_launch(run_parallel_test_and_modify ## size, &lworker, \
 		worker_lcore_id); \
 	TEST_ASSERT(rc == 0, "Worker thread launch failed"); \
@@ -266,7 +277,7 @@ test_bit_atomic_parallel_flip ## size(void) \
 		printf("Need multiple cores to run parallel test.\n"); \
 		return TEST_SKIPPED; \
 	} \
-	worker_lcore_id = rte_get_next_lcore(-1, 1, 0); \
+	worker_lcore_id = get_worker_lcore(); \
 	int rc = rte_eal_remote_launch(run_parallel_flip ## size, &lworker, worker_lcore_id); \
 	TEST_ASSERT(rc == 0, "Worker thread launch failed"); \
 	run_parallel_flip ## size(&lmain); \
-- 
2.46.2