[dpdk-dev] [PATCH] lcore: make semantics of lcore role function more intuitive

[Anatoly Burakov <anatoly.burakov@intel.com>]

rte_lcore_has_role() returns 0 if role of lcore matches requested
role. The return value of the API is confusing, and this is a known
problem with a deprecation notice announcing the change to more
intuitive semantics:

Commit 064518f68d48 ("doc: announce EAL API change to lcore role function")
Cc: erik.g.carrillo@intel.com

Implement changes announced in the deprecation notice, and remove it.
Also, fix usages of this API to reflect the change. Control thread patches
expected new behavior and were broken before, now they are fixed as well.

Fixes: d651ee4919cd ("eal: set affinity for control threads")
Cc: olivier.matz@6wind.com

Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
---
 doc/guides/rel_notes/deprecation.rst      | 5 -----
 lib/librte_eal/common/eal_common_thread.c | 5 +----
 lib/librte_timer/rte_timer.c              | 2 +-
 3 files changed, 2 insertions(+), 10 deletions(-)

diff --git a/doc/guides/rel_notes/deprecation.rst b/doc/guides/rel_notes/deprecation.rst
index 72ab33c..3353519 100644
--- a/doc/guides/rel_notes/deprecation.rst
+++ b/doc/guides/rel_notes/deprecation.rst
@@ -28,11 +28,6 @@ Deprecation Notices
   - ``eal_parse_pci_DomBDF`` replaced by ``rte_pci_addr_parse``
   - ``rte_eal_compare_pci_addr`` replaced by ``rte_pci_addr_cmp``
 
-* eal: The semantics of the return value for the ``rte_lcore_has_role`` function
-  are planned to change in v18.05. The function currently returns 0 and <0 for
-  success and failure, respectively.  This will change to 1 and 0 for true and
-  false, respectively, to make use of the function more intuitive.
-
 * eal: a new set of mbuf mempool ops name APIs for user, platform and best
   mempool names have been defined in ``rte_mbuf`` in v18.02. The uses of
   ``rte_eal_mbuf_default_mempool_ops`` shall be replaced by
diff --git a/lib/librte_eal/common/eal_common_thread.c b/lib/librte_eal/common/eal_common_thread.c
index 4e75cb8..fcf00cd 100644
--- a/lib/librte_eal/common/eal_common_thread.c
+++ b/lib/librte_eal/common/eal_common_thread.c
@@ -34,10 +34,7 @@ rte_lcore_has_role(unsigned int lcore_id, enum rte_lcore_role_t role)
 	if (lcore_id >= RTE_MAX_LCORE)
 		return -EINVAL;
 
-	if (cfg->lcore_role[lcore_id] == role)
-		return 0;
-
-	return -EINVAL;
+	return cfg->lcore_role[lcore_id] == role;
 }
 
 int eal_cpuset_socket_id(rte_cpuset_t *cpusetp)
diff --git a/lib/librte_timer/rte_timer.c b/lib/librte_timer/rte_timer.c
index 4bbcd06..590488c 100644
--- a/lib/librte_timer/rte_timer.c
+++ b/lib/librte_timer/rte_timer.c
@@ -403,7 +403,7 @@ rte_timer_reset(struct rte_timer *tim, uint64_t ticks,
 
 	if (unlikely((tim_lcore != (unsigned)LCORE_ID_ANY) &&
 			!(rte_lcore_is_enabled(tim_lcore) ||
-			  rte_lcore_has_role(tim_lcore, ROLE_SERVICE) == 0)))
+			  rte_lcore_has_role(tim_lcore, ROLE_SERVICE))))
 		return -1;
 
 	if (type == PERIODICAL)
-- 
2.7.4