Commit 7cae596b authored by Dylan Yudaken's avatar Dylan Yudaken Committed by Jens Axboe
Browse files

io_uring: register single issuer task at creation 



Instead of picking the task from the first submitter task, rather use the
creator task or in the case of disabled (IORING_SETUP_R_DISABLED) the
enabling task.

This approach allows a lot of simplification of the logic here. This
removes init logic from the submission path, which can always be a bit
confusing, but also removes the need for locking to write (or read) the
submitter_task.

Users that want to move a ring before submitting can create the ring
disabled and then enable it on the submitting task.

Signed-off-by: default avatarDylan Yudaken <dylany@fb.com>
Fixes: 97bbdc06 ("io_uring: add IORING_SETUP_SINGLE_ISSUER")
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent e775f93f

io_uring/io_uring.c

+7 −0
Original line number Diff line number Diff line
@@ -3357,6 +3357,10 @@ static __cold int io_uring_create(unsigned entries, struct io_uring_params *p, 
		goto err;

	}



	if (ctx->flags & IORING_SETUP_SINGLE_ISSUER

	    && !(ctx->flags & IORING_SETUP_R_DISABLED))

		ctx->submitter_task = get_task_struct(current);



	file = io_uring_get_file(ctx);

	if (IS_ERR(file)) {

		ret = PTR_ERR(file);
@@ -3548,6 +3552,9 @@ static int io_register_enable_rings(struct io_ring_ctx *ctx) 
	if (!(ctx->flags & IORING_SETUP_R_DISABLED))

		return -EBADFD;



	if (ctx->flags & IORING_SETUP_SINGLE_ISSUER && !ctx->submitter_task)

		ctx->submitter_task = get_task_struct(current);



	if (ctx->restrictions.registered)

		ctx->restricted = 1;