[PATCH v3] eventdev: avoid non-burst shortcut for variable-size bursts

["Mattias Rönnblom" <mattias.ronnblom@ericsson.com>]

Use non-burst event enqueue and dequeue calls from burst enqueue and
dequeue only when the burst size is compile-time constant (and equal
to one).

Signed-off-by: Mattias Rönnblom <mattias.ronnblom@ericsson.com>

---

v3: Actually include the change v2 claimed to contain.
v2: Wrap builtin call in __extension__, to avoid compiler warnings if
    application is compiled with -pedantic. (Morten Brørup)
---
 lib/eventdev/rte_eventdev.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/eventdev/rte_eventdev.h b/lib/eventdev/rte_eventdev.h
index a90e23ac8b..a471caeb6d 100644
--- a/lib/eventdev/rte_eventdev.h
+++ b/lib/eventdev/rte_eventdev.h
@@ -1944,7 +1944,7 @@ __rte_event_enqueue_burst(uint8_t dev_id, uint8_t port_id,
 	 * Allow zero cost non burst mode routine invocation if application
 	 * requests nb_events as const one
 	 */
-	if (nb_events == 1)
+	if (__extension__(__builtin_constant_p(nb_events)) && nb_events == 1)
 		return (fp_ops->enqueue)(port, ev);
 	else
 		return fn(port, ev, nb_events);
@@ -2200,7 +2200,7 @@ rte_event_dequeue_burst(uint8_t dev_id, uint8_t port_id, struct rte_event ev[],
 	 * Allow zero cost non burst mode routine invocation if application
 	 * requests nb_events as const one
 	 */
-	if (nb_events == 1)
+	if (__extension__(__builtin_constant_p(nb_events)) && nb_events == 1)
 		return (fp_ops->dequeue)(port, ev, timeout_ticks);
 	else
 		return (fp_ops->dequeue_burst)(port, ev, nb_events,
-- 
2.34.1