From: Jens Axboe Date: Mon, 11 Apr 2022 15:48:30 +0000 (-0600) Subject: io_uring: io_kiocb_update_pos() should not touch file for non -1 offset X-Git-Tag: v5.15.92~237 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=311b298a333707eb2523868bd3c85e6d4f457803;p=platform%2Fkernel%2Flinux-rpi.git io_uring: io_kiocb_update_pos() should not touch file for non -1 offset 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 Signed-off-by: Greg Kroah-Hartman --- diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index 78ed38d..be16883 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -3014,19 +3014,18 @@ 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 kiocb *kiocb, ssize_t ret,