[PATCH v3 1/2] liburing: add multishot timeout support

[David Wei <davidhwei@meta.com>]

Sync the new IORING_TIMEOUT_MULTISHOT flag with kernel.

Add unit tests for multishot timeouts.

Signed-off-by: David Wei <davidhwei@meta.com>
---
 src/include/liburing/io_uring.h |   1 +
 test/timeout.c                  | 263 ++++++++++++++++++++++++++++++++
 2 files changed, 264 insertions(+)

diff --git a/src/include/liburing/io_uring.h b/src/include/liburing/io_uring.h
index ec068d4..3d3a63b 100644
--- a/src/include/liburing/io_uring.h
+++ b/src/include/liburing/io_uring.h
@@ -250,6 +250,7 @@ enum io_uring_op {
 #define IORING_TIMEOUT_REALTIME		(1U << 3)
 #define IORING_LINK_TIMEOUT_UPDATE	(1U << 4)
 #define IORING_TIMEOUT_ETIME_SUCCESS	(1U << 5)
+#define IORING_TIMEOUT_MULTISHOT	(1U << 6)
 #define IORING_TIMEOUT_CLOCK_MASK	(IORING_TIMEOUT_BOOTTIME | IORING_TIMEOUT_REALTIME)
 #define IORING_TIMEOUT_UPDATE_MASK	(IORING_TIMEOUT_UPDATE | IORING_LINK_TIMEOUT_UPDATE)
 /*
diff --git a/test/timeout.c b/test/timeout.c
index 8c43832..6a9dd88 100644
--- a/test/timeout.c
+++ b/test/timeout.c
@@ -1327,6 +1327,235 @@ done:
 }
 
 
+static int test_timeout_multishot(struct io_uring *ring)
+{
+	struct io_uring_cqe *cqe;
+	struct io_uring_sqe *sqe;
+	struct __kernel_timespec ts;
+	int ret;
+
+	sqe = io_uring_get_sqe(ring);
+	if (!sqe) {
+		fprintf(stderr, "%s: get sqe failed\n", __FUNCTION__);
+		goto err;
+	}
+
+	msec_to_ts(&ts, TIMEOUT_MSEC);
+	io_uring_prep_timeout(sqe, &ts, 0, IORING_TIMEOUT_MULTISHOT);
+	io_uring_sqe_set_data(sqe, (void *) 1);
+
+	ret = io_uring_submit(ring);
+	if (ret <= 0) {
+		fprintf(stderr, "%s: sqe submit failed: %d\n", __FUNCTION__, ret);
+		goto err;
+	}
+
+	for (int i = 0; i < 2; i++) {
+		ret = io_uring_wait_cqe(ring, &cqe);
+		if (ret < 0) {
+			fprintf(stderr, "%s: wait completion %d\n", __FUNCTION__, ret);
+			goto err;
+		}
+
+		if (!(cqe->flags & IORING_CQE_F_MORE)) {
+			fprintf(stderr, "%s: flag not set in cqe\n", __FUNCTION__);
+			goto err;
+		}
+
+		ret = cqe->res;
+		if (ret != -ETIME) {
+			fprintf(stderr, "%s: Timeout: %s\n", __FUNCTION__, strerror(-ret));
+			goto err;
+		}
+
+		io_uring_cqe_seen(ring, cqe);
+	}
+
+	sqe = io_uring_get_sqe(ring);
+	if (!sqe) {
+		fprintf(stderr, "%s: get sqe failed\n", __FUNCTION__);
+		goto err;
+	}
+
+	io_uring_prep_timeout_remove(sqe, 1, 0);
+	io_uring_sqe_set_data(sqe, (void *) 2);
+
+	ret = io_uring_submit(ring);
+	if (ret <= 0) {
+		fprintf(stderr, "%s: sqe submit failed: %d\n", __FUNCTION__, ret);
+		goto err;
+	}
+
+	ret = io_uring_wait_cqe(ring, &cqe);
+	if (ret < 0) {
+		fprintf(stderr, "%s: wait completion %d\n", __FUNCTION__, ret);
+		goto err;
+	}
+
+	ret = cqe->res;
+	if (ret < 0) {
+		fprintf(stderr, "%s: remove failed: %s\n", __FUNCTION__, strerror(-ret));
+		goto err;
+	}
+
+	io_uring_cqe_seen(ring, cqe);
+
+	ret = io_uring_wait_cqe(ring, &cqe);
+	if (ret < 0) {
+		fprintf(stderr, "%s: wait completion %d\n", __FUNCTION__, ret);
+		goto err;
+	}
+
+	ret = cqe->res;
+	if (ret != -ECANCELED) {
+		fprintf(stderr, "%s: timeout canceled: %s %llu\n", __FUNCTION__, strerror(-ret), cqe->user_data);
+		goto err;
+	}
+
+	io_uring_cqe_seen(ring, cqe);
+	return 0;
+err:
+	return 1;
+}
+
+
+static int test_timeout_multishot_nr(struct io_uring *ring)
+{
+	struct io_uring_cqe *cqe;
+	struct io_uring_sqe *sqe;
+	struct __kernel_timespec ts;
+	int ret;
+
+	sqe = io_uring_get_sqe(ring);
+	if (!sqe) {
+		fprintf(stderr, "%s: get sqe failed\n", __FUNCTION__);
+		goto err;
+	}
+
+	msec_to_ts(&ts, TIMEOUT_MSEC);
+	io_uring_prep_timeout(sqe, &ts, 3, IORING_TIMEOUT_MULTISHOT);
+	io_uring_sqe_set_data(sqe, (void *) 1);
+
+	ret = io_uring_submit(ring);
+	if (ret <= 0) {
+		fprintf(stderr, "%s: sqe submit failed: %d\n", __FUNCTION__, ret);
+		goto err;
+	}
+
+	for (int i = 0; i < 3; i++) {
+		ret = io_uring_wait_cqe(ring, &cqe);
+		if (ret < 0) {
+			fprintf(stderr, "%s: wait completion %d\n", __FUNCTION__, ret);
+			goto err;
+		}
+
+		if (i < 2 && !(cqe->flags & IORING_CQE_F_MORE)) {
+			fprintf(stderr, "%s: flag not set in cqe\n", __FUNCTION__);
+			goto err;
+		}
+		if (i == 3 && (cqe->flags & IORING_CQE_F_MORE)) {
+			fprintf(stderr, "%s: flag set in cqe\n", __FUNCTION__);
+			goto err;
+		}
+
+		ret = cqe->res;
+		if (ret != -ETIME) {
+			fprintf(stderr, "%s: Timeout: %s\n", __FUNCTION__, strerror(-ret));
+			goto err;
+		}
+
+		io_uring_cqe_seen(ring, cqe);
+	}
+
+	msec_to_ts(&ts, 2 * TIMEOUT_MSEC);
+	ret = io_uring_wait_cqe_timeout(ring, &cqe, &ts);
+	if (ret != -ETIME) {
+		fprintf(stderr, "%s: wait completion timeout %s\n", __FUNCTION__, strerror(-ret));
+		goto err;
+	}
+
+	return 0;
+err:
+	return 1;
+}
+
+
+static int test_timeout_multishot_overflow(struct io_uring *ring)
+{
+	struct io_uring_cqe *cqe;
+	struct io_uring_sqe *sqe;
+	struct __kernel_timespec ts;
+	int ret;
+
+	sqe = io_uring_get_sqe(ring);
+	if (!sqe) {
+		fprintf(stderr, "%s: get sqe failed\n", __FUNCTION__);
+		goto err;
+	}
+
+	msec_to_ts(&ts, 10);
+	io_uring_prep_timeout(sqe, &ts, 0, IORING_TIMEOUT_MULTISHOT);
+	io_uring_sqe_set_data(sqe, (void *) 1);
+
+	ret = io_uring_submit(ring);
+	if (ret <= 0) {
+		fprintf(stderr, "%s: sqe submit failed: %d\n", __FUNCTION__, ret);
+		goto err;
+	}
+
+	ret = io_uring_wait_cqe(ring, &cqe);
+	if (ret < 0) {
+		fprintf(stderr, "%s: wait completion %d\n", __FUNCTION__, ret);
+		goto err;
+	}
+
+	ret = cqe->res;
+	if (ret != -ETIME) {
+		fprintf(stderr, "%s: Timeout: %s\n", __FUNCTION__, strerror(-ret));
+		goto err;
+	}
+
+	io_uring_cqe_seen(ring, cqe);
+	sleep(1);
+
+	if (!((*ring->sq.kflags) & IORING_SQ_CQ_OVERFLOW)) {
+		goto err;
+	}
+
+	/* multishot timer should be gone */
+	sqe = io_uring_get_sqe(ring);
+	if (!sqe) {
+		fprintf(stderr, "%s: get sqe failed\n", __FUNCTION__);
+		goto err;
+	}
+
+	io_uring_prep_timeout_remove(sqe, 1, 0);
+
+	ret = io_uring_submit(ring);
+	if (ret <= 0) {
+		fprintf(stderr, "%s: sqe submit failed: %d\n", __FUNCTION__, ret);
+		goto err;
+	}
+
+	ret = io_uring_wait_cqe(ring, &cqe);
+	if (ret < 0) {
+		fprintf(stderr, "%s: wait completion %d\n", __FUNCTION__, ret);
+		goto err;
+	}
+
+	ret = cqe->res;
+	io_uring_cqe_seen(ring, cqe);
+	if (ret != -ETIME) {
+		fprintf(stderr, "%s: remove failed: %d %s\n", __FUNCTION__, ret, strerror(-ret));
+		goto err;
+	}
+
+	return 0;
+err:
+	return 1;
+}
+
+
 int main(int argc, char *argv[])
 {
 	struct io_uring ring, sqpoll_ring;
@@ -1419,6 +1648,40 @@ int main(int argc, char *argv[])
 		return ret;
 	}
 
+	ret = test_timeout_multishot(&ring);
+	if (ret) {
+		fprintf(stderr, "test_timeout_multishot failed\n");
+		return ret;
+	}
+
+	ret = test_timeout_multishot_nr(&ring);
+	if (ret) {
+		fprintf(stderr, "test_timeout_multishot_nr failed\n");
+		return ret;
+	}
+
+	/* io_uring_wait_cqe_timeout() may have left a timeout, reinit ring */
+	io_uring_queue_exit(&ring);
+	ret = io_uring_queue_init(8, &ring, 0);
+	if (ret) {
+		fprintf(stderr, "ring setup failed\n");
+		return 1;
+	}
+
+	ret = test_timeout_multishot_overflow(&ring);
+	if (ret) {
+		fprintf(stderr, "test_timeout_multishot_overflow failed\n");
+		return ret;
+	}
+
+	/* io_uring_wait_cqe_timeout() may have left a timeout, reinit ring */
+	io_uring_queue_exit(&ring);
+	ret = io_uring_queue_init(8, &ring, 0);
+	if (ret) {
+		fprintf(stderr, "ring setup failed\n");
+		return 1;
+	}
+
 	ret = test_single_timeout_wait(&ring, &p);
 	if (ret) {
 		fprintf(stderr, "test_single_timeout_wait failed\n");
-- 
2.34.1