diff mbox series

[25/26] usb: gadget: dummy_hcd: replace usage of rc to check if a list element was found

Message ID 20220306175034.3084609-26-jakobkoschel@gmail.com
State New
Headers show
Series usb: gadget: remove usage of list iterator past the loop | expand

Commit Message

Jakob Koschel March 6, 2022, 5:50 p.m. UTC
To move the list iterator variable into the list_for_each_entry_*()
macro in the future it should be avoided to use the list iterator
variable after the loop body.

To *never* use the list iterator variable after the loop it was
concluded to use a separate iterator variable [1].

This removes the need to check the rc value to determine if the
break/goto was hit and can be made more obvious
by checking if the variable was set within the list traversal loop.

Link: https://lore.kernel.org/all/YhdfEIwI4EdtHdym@kroah.com/
Signed-off-by: Jakob Koschel <jakobkoschel@gmail.com>
---
 drivers/usb/gadget/udc/dummy_hcd.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

Comments

Greg Kroah-Hartman March 6, 2022, 6 p.m. UTC | #1
On Sun, Mar 06, 2022 at 06:50:33PM +0100, Jakob Koschel wrote:
> To move the list iterator variable into the list_for_each_entry_*()
> macro in the future it should be avoided to use the list iterator
> variable after the loop body.
> 
> To *never* use the list iterator variable after the loop it was
> concluded to use a separate iterator variable [1].
> 
> This removes the need to check the rc value to determine if the
> break/goto was hit and can be made more obvious
> by checking if the variable was set within the list traversal loop.
> 
> Link: https://lore.kernel.org/all/YhdfEIwI4EdtHdym@kroah.com/
> Signed-off-by: Jakob Koschel <jakobkoschel@gmail.com>
> ---
>  drivers/usb/gadget/udc/dummy_hcd.c | 11 ++++++-----
>  1 file changed, 6 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/usb/gadget/udc/dummy_hcd.c b/drivers/usb/gadget/udc/dummy_hcd.c
> index a2d956af42a2..f21944707707 100644
> --- a/drivers/usb/gadget/udc/dummy_hcd.c
> +++ b/drivers/usb/gadget/udc/dummy_hcd.c
> @@ -751,7 +751,7 @@ static int dummy_dequeue(struct usb_ep *_ep, struct usb_request *_req)
>  	struct dummy		*dum;
>  	int			retval = -EINVAL;
>  	unsigned long		flags;
> -	struct dummy_request	*req = NULL;
> +	struct dummy_request	*req = NULL, *tmp;
>  
>  	if (!_ep || !_req)
>  		return retval;
> @@ -763,17 +763,18 @@ static int dummy_dequeue(struct usb_ep *_ep, struct usb_request *_req)
>  
>  	local_irq_save(flags);
>  	spin_lock(&dum->lock);
> -	list_for_each_entry(req, &ep->queue, queue) {
> -		if (&req->req == _req) {
> -			list_del_init(&req->queue);
> +	list_for_each_entry(tmp, &ep->queue, queue) {
> +		if (&tmp->req == _req) {
> +			list_del_init(&tmp->queue);
>  			_req->status = -ECONNRESET;
> +			req = tmp;
>  			retval = 0;
>  			break;
>  		}
>  	}
>  	spin_unlock(&dum->lock);
>  
> -	if (retval == 0) {
> +	if (req) {

There's no need for this change as we are testing retval, not req here,
unlike the other udc drivers.

So this one I think is correct as-is, or am I mistaken somehow?

thanks,

greg k-h
diff mbox series

Patch

diff --git a/drivers/usb/gadget/udc/dummy_hcd.c b/drivers/usb/gadget/udc/dummy_hcd.c
index a2d956af42a2..f21944707707 100644
--- a/drivers/usb/gadget/udc/dummy_hcd.c
+++ b/drivers/usb/gadget/udc/dummy_hcd.c
@@ -751,7 +751,7 @@  static int dummy_dequeue(struct usb_ep *_ep, struct usb_request *_req)
 	struct dummy		*dum;
 	int			retval = -EINVAL;
 	unsigned long		flags;
-	struct dummy_request	*req = NULL;
+	struct dummy_request	*req = NULL, *tmp;
 
 	if (!_ep || !_req)
 		return retval;
@@ -763,17 +763,18 @@  static int dummy_dequeue(struct usb_ep *_ep, struct usb_request *_req)
 
 	local_irq_save(flags);
 	spin_lock(&dum->lock);
-	list_for_each_entry(req, &ep->queue, queue) {
-		if (&req->req == _req) {
-			list_del_init(&req->queue);
+	list_for_each_entry(tmp, &ep->queue, queue) {
+		if (&tmp->req == _req) {
+			list_del_init(&tmp->queue);
 			_req->status = -ECONNRESET;
+			req = tmp;
 			retval = 0;
 			break;
 		}
 	}
 	spin_unlock(&dum->lock);
 
-	if (retval == 0) {
+	if (req) {
 		dev_dbg(udc_dev(dum),
 				"dequeued req %p from %s, len %d buf %p\n",
 				req, _ep->name, _req->length, _req->buf);