Re: [PATCH 1/6] drivers: usb: remove usage of list iterator past the loop body

Dan Carpenter
2022-02-28T11:28:15Z

On Mon, Feb 28, 2022 at 12:08:17PM +0100, Jakob Koschel wrote:
> diff --git a/drivers/usb/gadget/udc/at91_udc.c b/drivers/usb/gadget/udc/at91_udc.c
> index 9040a0561466..0fd0307bc07b 100644
> --- a/drivers/usb/gadget/udc/at91_udc.c
> +++ b/drivers/usb/gadget/udc/at91_udc.c
> @@ -150,13 +150,14 @@ static void proc_ep_show(struct seq_file *s, struct at91_ep *ep)
> if (list_empty (&ep->queue))
> seq_printf(s, "\t(queue empty)\n");
>
> - else list_for_each_entry (req, &ep->queue, queue) {
> - unsigned length = req->req.actual;
> + else
> + list_for_each_entry(req, &ep->queue, queue) {
> + unsigned int length = req->req.actual;
>
> - seq_printf(s, "\treq %p len %d/%d buf %p\n",
> - &req->req, length,
> - req->req.length, req->req.buf);
> - }
> + seq_printf(s, "\treq %p len %d/%d buf %p\n",
> + &req->req, length,
> + req->req.length, req->req.buf);
> + }

Don't make unrelated white space changes. It just makes the patch
harder to review. As you're writing the patch make note of any
additional changes and do them later in a separate patch.

Also a multi-line indent gets curly braces for readability even though
it's not required by C. And then both sides would get curly braces.

> spin_unlock_irqrestore(&udc->lock, flags);
> }
>
> @@ -226,7 +227,7 @@ static int proc_udc_show(struct seq_file *s, void *unused)
>
> if (udc->enabled && udc->vbus) {
> proc_ep_show(s, &udc->ep[0]);
> - list_for_each_entry (ep, &udc->gadget.ep_list, ep.ep_list) {
> + list_for_each_entry(ep, &udc->gadget.ep_list, ep.ep_list) {

Another unrelated change.

> if (ep->ep.desc)
> proc_ep_show(s, ep);
> }

[ snip ]

> diff --git a/drivers/usb/gadget/udc/net2272.c b/drivers/usb/gadget/udc/net2272.c
> index 7c38057dcb4a..bb59200f1596 100644
> --- a/drivers/usb/gadget/udc/net2272.c
> +++ b/drivers/usb/gadget/udc/net2272.c
> @@ -926,7 +926,8 @@ static int
> net2272_dequeue(struct usb_ep *_ep, struct usb_request *_req)
> {
> struct net2272_ep *ep;
> - struct net2272_request *req;
> + struct net2272_request *req = NULL;
> + struct net2272_request *tmp;
> unsigned long flags;
> int stopped;
>
> @@ -939,11 +940,13 @@ net2272_dequeue(struct usb_ep *_ep, struct usb_request *_req)
> ep->stopped = 1;
>
> /* make sure it's still queued on this endpoint */
> - list_for_each_entry(req, &ep->queue, queue) {
> - if (&req->req == _req)
> + list_for_each_entry(tmp, &ep->queue, queue) {
> + if (&tmp->req == _req) {
> + req = tmp;
> break;
> + }
> }
> - if (&req->req != _req) {
> + if (!req) {
> ep->stopped = stopped;
> spin_unlock_irqrestore(&ep->dev->lock, flags);
> return -EINVAL;
> @@ -954,7 +957,6 @@ net2272_dequeue(struct usb_ep *_ep, struct usb_request *_req)
> dev_dbg(ep->dev->dev, "unlink (%s) pio\n", _ep->name);
> net2272_done(ep, req, -ECONNRESET);
> }
> - req = NULL;

Another unrelated change. These are all good changes but send them as
separate patches.

> ep->stopped = stopped;
>
> spin_unlock_irqrestore(&ep->dev->lock, flags);

regards,
dan carpenter