PCI: switchtec: Replace manual locks with guard

[PATCH] PCI: switchtec: Replace manual locks with guard

Posted by Erick Karanja 5 months, 1 week ago

Replace lock/unlock pairs with guards to simplify and tidy up the code

Generated-by: Coccinelle SmPL

Signed-off-by: Erick Karanja <karanja99erick@gmail.com>
---
 drivers/pci/switch/switchtec.c | 25 ++++++++++++-------------
 1 file changed, 12 insertions(+), 13 deletions(-)

diff --git a/drivers/pci/switch/switchtec.c b/drivers/pci/switch/switchtec.c
index b14dfab04d84..5ff84fb8fb0f 100644
--- a/drivers/pci/switch/switchtec.c
+++ b/drivers/pci/switch/switchtec.c
@@ -269,10 +269,9 @@ static void mrpc_event_work(struct work_struct *work)
 
 	dev_dbg(&stdev->dev, "%s\n", __func__);
 
-	mutex_lock(&stdev->mrpc_mutex);
+	guard(mutex)(&stdev->mrpc_mutex);
 	cancel_delayed_work(&stdev->mrpc_timeout);
 	mrpc_complete_cmd(stdev);
-	mutex_unlock(&stdev->mrpc_mutex);
 }
 
 static void mrpc_error_complete_cmd(struct switchtec_dev *stdev)
@@ -1322,18 +1321,18 @@ static void stdev_kill(struct switchtec_dev *stdev)
 	cancel_delayed_work_sync(&stdev->mrpc_timeout);
 
 	/* Mark the hardware as unavailable and complete all completions */
-	mutex_lock(&stdev->mrpc_mutex);
-	stdev->alive = false;
-
-	/* Wake up and kill any users waiting on an MRPC request */
-	list_for_each_entry_safe(stuser, tmpuser, &stdev->mrpc_queue, list) {
-		stuser->cmd_done = true;
-		wake_up_interruptible(&stuser->cmd_comp);
-		list_del_init(&stuser->list);
-		stuser_put(stuser);
-	}
+	scoped_guard (mutex, &stdev->mrpc_mutex) {
+		stdev->alive = false;
+
+		/* Wake up and kill any users waiting on an MRPC request */
+		list_for_each_entry_safe(stuser, tmpuser, &stdev->mrpc_queue, list) {
+			stuser->cmd_done = true;
+			wake_up_interruptible(&stuser->cmd_comp);
+			list_del_init(&stuser->list);
+			stuser_put(stuser);
+		}
 
-	mutex_unlock(&stdev->mrpc_mutex);
+	}
 
 	/* Wake up any users waiting on event_wq */
 	wake_up_interruptible(&stdev->event_wq);
-- 
2.43.0

Re: [PATCH] PCI: switchtec: Replace manual locks with guard

Posted by Bjorn Helgaas 5 months, 1 week ago

On Thu, Aug 28, 2025 at 12:35:55PM +0300, Erick Karanja wrote:
> Replace lock/unlock pairs with guards to simplify and tidy up the code
> 
> Generated-by: Coccinelle SmPL
> 
> Signed-off-by: Erick Karanja <karanja99erick@gmail.com>

Applied to pci/switchtec for v6.18, thanks, Erick!

> ---
>  drivers/pci/switch/switchtec.c | 25 ++++++++++++-------------
>  1 file changed, 12 insertions(+), 13 deletions(-)
> 
> diff --git a/drivers/pci/switch/switchtec.c b/drivers/pci/switch/switchtec.c
> index b14dfab04d84..5ff84fb8fb0f 100644
> --- a/drivers/pci/switch/switchtec.c
> +++ b/drivers/pci/switch/switchtec.c
> @@ -269,10 +269,9 @@ static void mrpc_event_work(struct work_struct *work)
>  
>  	dev_dbg(&stdev->dev, "%s\n", __func__);
>  
> -	mutex_lock(&stdev->mrpc_mutex);
> +	guard(mutex)(&stdev->mrpc_mutex);
>  	cancel_delayed_work(&stdev->mrpc_timeout);
>  	mrpc_complete_cmd(stdev);
> -	mutex_unlock(&stdev->mrpc_mutex);
>  }
>  
>  static void mrpc_error_complete_cmd(struct switchtec_dev *stdev)
> @@ -1322,18 +1321,18 @@ static void stdev_kill(struct switchtec_dev *stdev)
>  	cancel_delayed_work_sync(&stdev->mrpc_timeout);
>  
>  	/* Mark the hardware as unavailable and complete all completions */
> -	mutex_lock(&stdev->mrpc_mutex);
> -	stdev->alive = false;
> -
> -	/* Wake up and kill any users waiting on an MRPC request */
> -	list_for_each_entry_safe(stuser, tmpuser, &stdev->mrpc_queue, list) {
> -		stuser->cmd_done = true;
> -		wake_up_interruptible(&stuser->cmd_comp);
> -		list_del_init(&stuser->list);
> -		stuser_put(stuser);
> -	}
> +	scoped_guard (mutex, &stdev->mrpc_mutex) {
> +		stdev->alive = false;
> +
> +		/* Wake up and kill any users waiting on an MRPC request */
> +		list_for_each_entry_safe(stuser, tmpuser, &stdev->mrpc_queue, list) {
> +			stuser->cmd_done = true;
> +			wake_up_interruptible(&stuser->cmd_comp);
> +			list_del_init(&stuser->list);
> +			stuser_put(stuser);
> +		}
>  
> -	mutex_unlock(&stdev->mrpc_mutex);
> +	}
>  
>  	/* Wake up any users waiting on event_wq */
>  	wake_up_interruptible(&stdev->event_wq);
> -- 
> 2.43.0
>

Re: [PATCH] PCI: switchtec: Replace manual locks with guard

Posted by Logan Gunthorpe 5 months, 1 week ago


On 2025-08-28 03:35, Erick Karanja wrote:
> Replace lock/unlock pairs with guards to simplify and tidy up the code
> 
> Generated-by: Coccinelle SmPL
> 
> Signed-off-by: Erick Karanja <karanja99erick@gmail.com>

Looks good to me, thanks!

Reviewed-by: Logan Gunthorpe <logang@deltatee.com>