Commit 6f83ab22 authored by Jens Axboe's avatar Jens Axboe
Browse files

io_uring: io_kiocb_update_pos() should not touch file for non -1 offset 



-1 tells use to use the current position, but we check if the file is
a stream regardless of that. Fix up io_kiocb_update_pos() to only
dip into file if we need to. This is both more efficient and also drops
12 bytes of text on aarch64 and 64 bytes on x86-64.

Fixes: b4aec400 ("io_uring: do not recalculate ppos unnecessarily")
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent c4212f3e

fs/io_uring.c

+10 −11
Original line number Diff line number Diff line
@@ -3183,20 +3183,19 @@ static inline void io_rw_done(struct kiocb *kiocb, ssize_t ret) 
static inline loff_t *io_kiocb_update_pos(struct io_kiocb *req)

{

	struct kiocb *kiocb = &req->rw.kiocb;

	bool is_stream = req->file->f_mode & FMODE_STREAM;



	if (kiocb->ki_pos == -1) {

		if (!is_stream) {

	if (kiocb->ki_pos != -1)

		return &kiocb->ki_pos;



	if (!(req->file->f_mode & FMODE_STREAM)) {

		req->flags |= REQ_F_CUR_POS;

		kiocb->ki_pos = req->file->f_pos;

		return &kiocb->ki_pos;

		} else {

	}



	kiocb->ki_pos = 0;

	return NULL;

}

	}

	return is_stream ? NULL : &kiocb->ki_pos;

}



static void kiocb_done(struct io_kiocb *req, ssize_t ret,

		       unsigned int issue_flags)