[PATCH liburing v2] tests: add another timeout sequence test case

[Marcelo Diop-Gonzalez <marcelo827@xxxxxxxxx>]

This test case catches an issue where timeouts may not be flushed
if the number of new events is greater (not equal) to the number
of events requested in the timeout.

Signed-off-by: Marcelo Diop-Gonzalez <marcelo827@xxxxxxxxx>
---

v2: Don't assume the timeout should be last when nr < 2.

 test/timeout.c | 40 +++++++++++++++++++---------------------
 1 file changed, 19 insertions(+), 21 deletions(-)

diff --git a/test/timeout.c b/test/timeout.c
index 9c8211c..a28d599 100644
--- a/test/timeout.c
+++ b/test/timeout.c
@@ -112,7 +112,7 @@ err:
 /*
  * Test numbered trigger of timeout
  */
-static int test_single_timeout_nr(struct io_uring *ring)
+static int test_single_timeout_nr(struct io_uring *ring, int nr)
 {
 	struct io_uring_cqe *cqe;
 	struct io_uring_sqe *sqe;
@@ -126,7 +126,7 @@ static int test_single_timeout_nr(struct io_uring *ring)
 	}
 
 	msec_to_ts(&ts, TIMEOUT_MSEC);
-	io_uring_prep_timeout(sqe, &ts, 2, 0);
+	io_uring_prep_timeout(sqe, &ts, nr, 0);
 
 	sqe = io_uring_get_sqe(ring);
 	io_uring_prep_nop(sqe);
@@ -149,33 +149,26 @@ static int test_single_timeout_nr(struct io_uring *ring)
 			goto err;
 		}
 
+		ret = cqe->res;
+
 		/*
 		 * NOP commands have user_data as 1. Check that we get the
-		 * two NOPs first, then the successfully removed timout as
-		 * the last one.
+		 * at least 'nr' NOPs first, then the successfully removed timout.
 		 */
-		switch (i) {
-		case 0:
-		case 1:
-			if (io_uring_cqe_get_data(cqe) != (void *) 1) {
-				fprintf(stderr, "%s: nop not seen as 1 or 2\n", __FUNCTION__);
+		if (io_uring_cqe_get_data(cqe) == NULL) {
+			if (i < nr) {
+				fprintf(stderr, "%s: timeout received too early\n", __FUNCTION__);
 				goto err;
 			}
-			break;
-		case 2:
-			if (io_uring_cqe_get_data(cqe) != NULL) {
-				fprintf(stderr, "%s: timeout not last\n", __FUNCTION__);
+			if (ret) {
+				fprintf(stderr, "%s: timeout triggered by passage of"
+					" time, not by events completed\n", __FUNCTION__);
 				goto err;
 			}
-			break;
 		}
 
-		ret = cqe->res;
 		io_uring_cqe_seen(ring, cqe);
-		if (ret < 0) {
-			fprintf(stderr, "Timeout: %s\n", strerror(-ret));
-			goto err;
-		} else if (ret) {
+		if (ret) {
 			fprintf(stderr, "res: %d\n", ret);
 			goto err;
 		}
@@ -1224,9 +1217,14 @@ int main(int argc, char *argv[])
 		return ret;
 	}
 
-	ret = test_single_timeout_nr(&ring);
+	ret = test_single_timeout_nr(&ring, 1);
+	if (ret) {
+		fprintf(stderr, "test_single_timeout_nr(1) failed\n");
+		return ret;
+	}
+	ret = test_single_timeout_nr(&ring, 2);
 	if (ret) {
-		fprintf(stderr, "test_single_timeout_nr failed\n");
+		fprintf(stderr, "test_single_timeout_nr(2) failed\n");
 		return ret;
 	}
 
-- 
2.20.1