Re: [PATCH 3/3] io_uring: move struct io_kiocb from task_struct to io_uring_task

[Pavel Begunkov <asml.silence@gmail.com>]

On 11/3/24 17:49, Jens Axboe wrote:
> Rather than store the task_struct itself in struct io_kiocb, store
> the io_uring specific task_struct. The life times are the same in terms
> of io_uring, and this avoids doing some dereferences through the
> task_struct. For the hot path of putting local task references, we can

Makes me wonder, is __io_submit_flush_completions() the only hot
place it tries to improve? It doesn't have to look into the task
there but on the other hand we need to do it that init.
If that's costly, for DEFER_TASKRUN we can get rid of per task
counting, the task is pinned together with the ctx, and the task
exit path can count the number of requests allocated.

if (!(ctx->flags & DEFER_TASKRUN))
	io_task_get_ref();

if (!(ctx->flags & DEFER_TASKRUN))
	io_task_put_ref();

But can be further improved

-- 
Pavel Begunkov