[dpdk-dev] [PATCH] test/interrupt: account for race with callback

[Aaron Conole]

Because the eal interrupt framework can race when invoking the callback
and a separate unregister call, the test needs to accommodate the chance
that the two collide.  Do this by checking the return value of unregister
against the race-condition flag (EAGAIN).

Fixes: f1a6c22424ce ("app/test: update interrupts test")
Signed-off-by: Aaron Conole <aconole at redhat.com>
---
NOTE: it's difficult to reproduce this race.  I tried a bit, but have
      only seen it sporadically.  In Travis environment, the CPU
      resource can be very limited and this test is quite racy.

 app/test/test_interrupts.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/app/test/test_interrupts.c b/app/test/test_interrupts.c
index d8c2d8124..233b14a70 100644
--- a/app/test/test_interrupts.c
+++ b/app/test/test_interrupts.c
@@ -370,9 +370,13 @@ test_interrupt_full_path_check(enum test_interrupt_handle_type intr_type)
 		rte_delay_ms(TEST_INTERRUPT_CHECK_INTERVAL);
 
 	rte_delay_ms(TEST_INTERRUPT_CHECK_INTERVAL);
-	if (rte_intr_callback_unregister(&test_intr_handle,
-			test_interrupt_callback, &test_intr_handle) < 0)
-		return -1;
+	while ((count =
+		rte_intr_callback_unregister(&test_intr_handle,
+					     test_interrupt_callback,
+					     &test_intr_handle)) < 0) {
+		if (count != -EAGAIN)
+			return -1;
+	}
 
 	if (flag == 0) {
 		printf("callback has not been called\n");
-- 
2.21.0