On 10/4/21 7:31 AM, Olivier Langlois wrote:
> before commit 0ea4ccd1c0e4 ("src/queue: don't flush SQ ring for new wait interface"),
> io_uring_wait_cqes() was serving the purpose of submit sqe and wait for cqe up to a certain timeout value.
>
> Since the commit, a new function is needed to fill this gap.
>
> Fixes: https://github.com/axboe/liburing/issues/440
> Signed-off-by: Olivier Langlois <olivier@xxxxxxxxxxxxxx>
> ---
> src/include/liburing.h | 5 +++++
> src/liburing.map | 5 +++++
> src/queue.c | 33 +++++++++++++++++++++++++++++++++
> 3 files changed, 43 insertions(+)
>
> diff --git a/src/include/liburing.h b/src/include/liburing.h
> index 0c2c5c2..fe8bfbe 100644
> --- a/src/include/liburing.h
> +++ b/src/include/liburing.h
> @@ -122,6 +122,11 @@ int io_uring_wait_cqe_timeout(struct io_uring *ring,
> struct __kernel_timespec *ts);
> int io_uring_submit(struct io_uring *ring);
> int io_uring_submit_and_wait(struct io_uring *ring, unsigned wait_nr);
> +int io_uring_submit_and_wait_timout(struct io_uring *ring,
> + struct io_uring_cqe **cqe_ptr,
> + unsigned wait_nr,
> + struct __kernel_timespec *ts,
> + sigset_t *sigmask);
> struct io_uring_sqe *io_uring_get_sqe(struct io_uring *ring);
>
> int io_uring_register_buffers(struct io_uring *ring, const struct iovec *iovecs,
> diff --git a/src/liburing.map b/src/liburing.map
> index 6692a3b..09f4275 100644
> --- a/src/liburing.map
> +++ b/src/liburing.map
> @@ -44,3 +44,8 @@ LIBURING_2.1 {
> io_uring_unregister_iowq_aff;
> io_uring_register_iowq_max_workers;
> } LIBURING_2.0;
> +
> +LIBURING_2.2 {
> + global:
> + io_uring_submit_and_wait_timout;
> +} LIBURING_2.1;
> diff --git a/src/queue.c b/src/queue.c
> index 31aa17c..9ac9fe5 100644
> --- a/src/queue.c
> +++ b/src/queue.c
> @@ -305,6 +305,39 @@ int io_uring_wait_cqes(struct io_uring *ring, struct io_uring_cqe **cqe_ptr,
> return __io_uring_get_cqe(ring, cqe_ptr, to_submit, wait_nr, sigmask);
> }
>
> +int io_uring_submit_and_wait_timout(struct io_uring *ring,
> + struct io_uring_cqe **cqe_ptr,
> + unsigned wait_nr,
> + struct __kernel_timespec *ts,
> + sigset_t *sigmask)
> +{
> + if (uring_likely(ts)) {
> + if (uring_unlikely(!(ring->features & IORING_FEAT_EXT_ARG)))
> + return io_uring_wait_cqes(ring, cqe_ptr, wait_nr,
> + ts, sigmask);
> + else {
> + struct io_uring_getevents_arg arg = {
> + .sigmask = (unsigned long) sigmask,
> + .sigmask_sz = _NSIG / 8,
> + .ts = (unsigned long) ts
> + };
> + struct get_data data = {
> + .submit = __io_uring_flush_sq(ring),
> + .wait_nr = wait_nr,
> + .get_flags = IORING_ENTER_EXT_ARG,
> + .sz = sizeof(arg),
> + .arg = &arg
> + };
> +
> + return _io_uring_get_cqe(ring, cqe_ptr, &data);
> + }
> + }
> + else
> + return __io_uring_get_cqe(ring, cqe_ptr,
> + __io_uring_flush_sq(ring),
> + wait_nr, sigmask);
> +}
I'd get rid of the likely/unlikely, imho it just hinders readability
and for some cases they may end up being wrong. You also don't need an
else when there's a return, and if you use braces on one condition, use
it for all. IOW, something like:
if (ts) {
if (ring->features & IORING_FEAT_EXT_ARG) {
struct io_uring_getevents_arg arg = {
.sigmask = (unsigned long) sigmask,
.sigmask_sz = _NSIG / 8,
.ts = (unsigned long) ts
};
struct get_data data = {
.submit = __io_uring_flush_sq(ring),
.wait_nr = wait_nr,
.get_flags = IORING_ENTER_EXT_ARG,
.sz = sizeof(arg),
.arg = &arg
};
return _io_uring_get_cqe(ring, cqe_ptr, &data);
}
return io_uring_wait_cqes(ring, cqe_ptr, wait_nr, ts, sigmask);
}
return __io_uring_get_cqe(ring, cqe_ptr, __io_uring_flush_sq(ring),
wait_nr, sigmask);
which is a lot more readable too.
--
Jens Axboe
