io_uring: fix miscounting ios_left
authorPavel Begunkov <asml.silence@gmail.com>
Fri, 20 Nov 2020 15:50:51 +0000 (15:50 +0000)
committerJens Axboe <axboe@kernel.dk>
Wed, 9 Dec 2020 19:04:01 +0000 (12:04 -0700)
io_req_init() doesn't decrement state->ios_left if a request doesn't
need ->file, it just returns before that on if(!needs_file). That's
not really a problem but may cause overhead for an additional fput().
Also inline and kill io_req_set_file() as it's of no use anymore.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
fs/io_uring.c

index a83593c..9153694 100644 (file)
@@ -6327,15 +6327,6 @@ static struct file *io_file_get(struct io_submit_state *state,
        return file;
 }
 
-static int io_req_set_file(struct io_submit_state *state, struct io_kiocb *req,
-                          int fd)
-{
-       req->file = io_file_get(state, req, fd, req->flags & REQ_F_FIXED_FILE);
-       if (req->file || io_op_defs[req->opcode].needs_file_no_error)
-               return 0;
-       return -EBADF;
-}
-
 static enum hrtimer_restart io_link_timeout_fn(struct hrtimer *timer)
 {
        struct io_timeout_data *data = container_of(timer,
@@ -6748,10 +6739,16 @@ static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req,
                state->plug_started = true;
        }
 
-       if (!io_op_defs[req->opcode].needs_file)
-               return 0;
+       ret = 0;
+       if (io_op_defs[req->opcode].needs_file) {
+               bool fixed = req->flags & REQ_F_FIXED_FILE;
+
+               req->file = io_file_get(state, req, READ_ONCE(sqe->fd), fixed);
+               if (unlikely(!req->file &&
+                   !io_op_defs[req->opcode].needs_file_no_error))
+                       ret = -EBADF;
+       }
 
-       ret = io_req_set_file(state, req, READ_ONCE(sqe->fd));
        state->ios_left--;
        return ret;
 }