Commit 59169439 authored by Pavel Begunkov's avatar Pavel Begunkov Committed by Jens Axboe
Browse files

io_uring: conditional ->async_data allocation 



There are opcodes that need ->async_data only in some cases and
allocation it unconditionally may hurt performance. Add an option to
opdef to make move the allocation part from the core io_uring to opcode
specific code.
Note, we can't just set opdef->async_size to zero because there are
other helpers that rely on it, e.g. io_alloc_async_data().

Signed-off-by: default avatarPavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/9dc62be9e88dd0ed63c48365340e8922d2498293.1661342812.git.asml.silence@gmail.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 53bdc88a

io_uring/io_uring.c

+4 −3
Original line number Diff line number Diff line
@@ -1450,9 +1450,10 @@ int io_req_prep_async(struct io_kiocb *req) 
		return 0;

	if (WARN_ON_ONCE(req_has_async_data(req)))

		return -EFAULT;

	if (!io_op_defs[req->opcode].manual_alloc) {

		if (io_alloc_async_data(req))

			return -EAGAIN;



	}

	return def->prep_async(req);

}

io_uring/opdef.h

+2 −0
Original line number Diff line number Diff line
@@ -25,6 +25,8 @@ struct io_op_def { 
	unsigned		ioprio : 1;

	/* supports iopoll */

	unsigned		iopoll : 1;

	/* opcode specific path will handle ->async_data allocation if needed */

	unsigned		manual_alloc : 1;

	/* size of async data needed, if any */

	unsigned short		async_size;