Commit 5be9ad1e authored by Pavel Begunkov's avatar Pavel Begunkov Committed by Jens Axboe
Browse files

io_uring: optimise io_init_req() flags setting 



Invalid req->flags are tolerated by free/put well, avoid this dancing
needlessly presetting it to zero, and then not even resetting but
modifying it, i.e. "|=".

Signed-off-by: default avatarPavel Begunkov <asml.silence@gmail.com>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent cdbff982

fs/io_uring.c

+7 −10
Original line number Diff line number Diff line
@@ -6806,14 +6806,15 @@ static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req, 
{

	struct io_submit_state *state;

	unsigned int sqe_flags;

	int id, ret;

	int id, ret = 0;



	req->opcode = READ_ONCE(sqe->opcode);

	/* same numerical values with corresponding REQ_F_*, safe to copy */

	req->flags = sqe_flags = READ_ONCE(sqe->flags);

	req->user_data = READ_ONCE(sqe->user_data);

	req->async_data = NULL;

	req->file = NULL;

	req->ctx = ctx;

	req->flags = 0;

	req->link = NULL;

	req->fixed_rsrc_refs = NULL;

	/* one is dropped after submission, the other at completion */
@@ -6821,17 +6822,16 @@ static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req, 
	req->task = current;

	req->result = 0;



	/* enforce forwards compatibility on users */

	if (unlikely(sqe_flags & ~SQE_VALID_FLAGS))

		return -EINVAL;



	if (unlikely(req->opcode >= IORING_OP_LAST))

		return -EINVAL;



	if (unlikely(io_sq_thread_acquire_mm_files(ctx, req)))

		return -EFAULT;



	sqe_flags = READ_ONCE(sqe->flags);

	/* enforce forwards compatibility on users */

	if (unlikely(sqe_flags & ~SQE_VALID_FLAGS))

		return -EINVAL;



	if (unlikely(!io_check_restriction(ctx, req, sqe_flags)))

		return -EACCES;
@@ -6854,8 +6854,6 @@ static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req, 
		req->work.flags |= IO_WQ_WORK_CREDS;

	}



	/* same numerical values with corresponding REQ_F_*, safe to copy */

	req->flags |= sqe_flags;

	state = &ctx->submit_state;



	/*
@@ -6868,7 +6866,6 @@ static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req, 
		state->plug_started = true;

	}



	ret = 0;

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

		bool fixed = req->flags & REQ_F_FIXED_FILE;