From: Jens Axboe <axboe@xxxxxxxxx>
commit 6f83ab22adcb77a5824d2c274dace0d99e21319f upstream.
-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 <axboe@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
io_uring/io_uring.c | 21 ++++++++++-----------
1 file changed, 10 insertions(+), 11 deletions(-)
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -3011,19 +3011,18 @@ static inline void io_rw_done(struct kio
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 kiocb *kiocb, ssize_t ret,
