1 /* SPDX-License-Identifier: MIT */
2 /*
3 * Description: test CQ ring overflow
4 *
5 */
6 #include <errno.h>
7 #include <stdio.h>
8 #include <unistd.h>
9 #include <stdlib.h>
10 #include <string.h>
11 #include <fcntl.h>
12
13 #include "liburing.h"
14
queue_n_nops(struct io_uring * ring,int n)15 static int queue_n_nops(struct io_uring *ring, int n)
16 {
17 struct io_uring_sqe *sqe;
18 int i, ret;
19
20 for (i = 0; i < n; i++) {
21 sqe = io_uring_get_sqe(ring);
22 if (!sqe) {
23 printf("get sqe failed\n");
24 goto err;
25 }
26
27 io_uring_prep_nop(sqe);
28 }
29
30 ret = io_uring_submit(ring);
31 if (ret < n) {
32 printf("Submitted only %d\n", ret);
33 goto err;
34 } else if (ret < 0) {
35 printf("sqe submit failed: %d\n", ret);
36 goto err;
37 }
38
39 return 0;
40 err:
41 return 1;
42 }
43
main(int argc,char * argv[])44 int main(int argc, char *argv[])
45 {
46 struct io_uring_cqe *cqe;
47 struct io_uring_params p;
48 struct io_uring ring;
49 int i, ret;
50
51 if (argc > 1)
52 return 0;
53
54 memset(&p, 0, sizeof(p));
55 ret = io_uring_queue_init_params(4, &ring, &p);
56 if (ret) {
57 printf("ring setup failed\n");
58 return 1;
59
60 }
61
62 if (queue_n_nops(&ring, 4))
63 goto err;
64 if (queue_n_nops(&ring, 4))
65 goto err;
66 if (queue_n_nops(&ring, 4))
67 goto err;
68
69 i = 0;
70 do {
71 ret = io_uring_peek_cqe(&ring, &cqe);
72 if (ret < 0) {
73 if (ret == -EAGAIN)
74 break;
75 printf("wait completion %d\n", ret);
76 goto err;
77 }
78 io_uring_cqe_seen(&ring, cqe);
79 if (!cqe)
80 break;
81 i++;
82 } while (1);
83
84 if (i < 8 ||
85 ((*ring.cq.koverflow != 4) && !(p.features & IORING_FEAT_NODROP))) {
86 printf("CQ overflow fail: %d completions, %u overflow\n", i,
87 *ring.cq.koverflow);
88 goto err;
89 }
90
91 io_uring_queue_exit(&ring);
92 return 0;
93 err:
94 io_uring_queue_exit(&ring);
95 return 1;
96 }
97