From 6f83ab22adcb77a5824d2c274dace0d99e21319f Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Mon, 11 Apr 2022 09:48:30 -0600 Subject: [PATCH] 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: b4aec4001595 ("io_uring: do not recalculate ppos unnecessarily") Signed-off-by: Jens Axboe --- fs/io_uring.c | 21 ++++++++++----------- 1 file changed, 10 insertions(+), 11 deletions(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index f060ad0..b4a5e2a 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -3183,19 +3183,18 @@ 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) { - req->flags |= REQ_F_CUR_POS; - kiocb->ki_pos = req->file->f_pos; - return &kiocb->ki_pos; - } else { - kiocb->ki_pos = 0; - return NULL; - } + 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; } - return is_stream ? NULL : &kiocb->ki_pos; + + kiocb->ki_pos = 0; + return NULL; } static void kiocb_done(struct io_kiocb *req, ssize_t ret, -- 2.7.4