Re: [PATCHv6] io_uring: add support for IORING_SETUP_SQE_MIXED

[Jens Axboe <axboe@kernel.dk>]

On 10/22/25 6:00 AM, Nathan Chancellor wrote:
> On Tue, Oct 21, 2025 at 04:02:28PM -0600, Jens Axboe wrote:
>>
>> On Thu, 16 Oct 2025 11:09:38 -0700, Keith Busch wrote:
>>> Normal rings support 64b SQEs for posting submissions, while certain
>>> features require the ring to be configured with IORING_SETUP_SQE128, as
>>> they need to convey more information per submission. This, in turn,
>>> makes ALL the SQEs be 128b in size. This is somewhat wasteful and
>>> inefficient, particularly when only certain SQEs need to be of the
>>> bigger variant.
>>>
>>> [...]
>>
>> Applied, thanks!
>>
>> [1/1] io_uring: add support for IORING_SETUP_SQE_MIXED
>>       commit: 31dc41afdef21f264364288a30013b538c46152e
> 
> This needs a pretty obvious fix up as clang points out:
> 
>   io_uring/fdinfo.c:103:22: error: variable 'sqe' is uninitialized when used here [-Werror,-Wuninitialized]
>     103 |                 opcode = READ_ONCE(sqe->opcode);
>         |                                    ^~~
> 
> I would have sent a formal patch but since it is at the top, I figured
> it would get squashed anyways.

Indeed - I'll fold this in. Keith, can you add an fdinfo test case for
mixed as well?

-- 
Jens Axboe