Re: [PATCH] io_uring: pass struct io_tw_state by value
From: Jens Axboe
Date: Wed Feb 12 2025 - 09:33:15 EST
On 2/11/25 2:45 PM, Caleb Sander Mateos wrote:
> 8e5b3b89ecaf ("io_uring: remove struct io_tw_state::locked") removed the
> only field of io_tw_state but kept it as a task work callback argument
> to "forc[e] users not to invoke them carelessly out of a wrong context".
> Passing the struct io_tw_state * argument adds a few instructions to all
> callers that can't inline the functions and see the argument is unused.
>
> So pass struct io_tw_state by value instead. Since it's a 0-sized value,
> it can be passed without any instructions needed to initialize it.
>
> Also add a comment to struct io_tw_state to explain its purpose.
This is nice, reduces the code generated. It'll conflict with the
fix that Pavel posted, but I can just mangle this one once I get
the 6.15 branch rebased on top of -rc3. No need to send a v2.
--
Jens Axboe