On 11/20/2019 5:03 PM, Bob Liu wrote:
> I see, thanks.
> As for me, it may better return -EINVAL in advance so as to skip a lot unnecessary code for those reqs.
>
Hah, I removed similar check just yesterday (see [PATCH 3/4] "io_uring:
remove redundant check"). We don't care about performance of invalid
requests, and this one in hot-path. The fewer edge cases, the better.
Also, for the example below, I'd want to fail INVALID_REQ and cancel
valid ones, but not exit after processing invalid, or even worse
processing the rest without it.
INVALID_REQ -> VALID_REQ -> VALID_REQ.
> @@ -3176,6 +3176,7 @@ static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr,
>
> if (!io_get_sqring(ctx, &req->submit)) {
> }
> ...
> + if (unlikely(req_is_invalid(req)))
> + return -EINVAL;
>
--
Pavel Begunkov
