mini_liburing.h is used by the io_uring tests as a stand-in for liburing. The next patch in this series needs the io_uring_peek_cqe function, and I speculate that future tests will too, so add that here.
Please scrutinize this code, I am somewhat new to io_uring, and whilst I have tested this and know it to work, I very well could've made a mistake somewhere without noticing. Signed-off-by: Oliver Crumrine <[email protected]> --- tools/include/io_uring/mini_liburing.h | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/tools/include/io_uring/mini_liburing.h b/tools/include/io_uring/mini_liburing.h index 9ccb16074eb5..94dcc7f9aa33 100644 --- a/tools/include/io_uring/mini_liburing.h +++ b/tools/include/io_uring/mini_liburing.h @@ -182,6 +182,24 @@ static inline int io_uring_wait_cqe(struct io_uring *ring, return 0; } +static inline int io_uring_peek_cqe(struct io_uring *ring, + struct io_uring_cqe **cqe_ptr) +{ + struct io_uring_cq *cq = &ring->cq; + const unsigned int mask = *cq->kring_mask; + unsigned int head = *cq->khead; + unsigned int tail = *cq->ktail; + + *cqe_ptr = NULL; + + read_barrier(); + if (head-tail) { + *cqe_ptr = &cq->cqes[head & mask]; + return 0; + } + return -EAGAIN; +} + static inline int io_uring_submit(struct io_uring *ring) { struct io_uring_sq *sq = &ring->sq; -- 2.44.0
