[PATCH v2 1/4] ACPI: PCI: Use a mutex guard to simplify acpi_get_pci_dev()

Posted by Rafael J. Wysocki 1 week, 2 days ago

From: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>

Use a mutex guard in acpi_get_pci_dev() for the physical_node_lock
locking and drop local variable pci_dev that becomes redundant after
that change.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---

v1 -> v2:
   * Add cleanup.h include to pci_root.c (Andy)

---
 drivers/acpi/pci_root.c | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
index 4c06c3ffd0cb..d0dafc38b0cf 100644
--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -8,6 +8,7 @@
 
 #define pr_fmt(fmt) "ACPI: " fmt
 
+#include <linux/cleanup.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/init.h>
@@ -307,24 +308,20 @@ struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
 {
 	struct acpi_device *adev = acpi_fetch_acpi_dev(handle);
 	struct acpi_device_physical_node *pn;
-	struct pci_dev *pci_dev = NULL;
 
 	if (!adev)
 		return NULL;
 
-	mutex_lock(&adev->physical_node_lock);
+	guard(mutex)(&adev->physical_node_lock);
 
 	list_for_each_entry(pn, &adev->physical_node_list, node) {
 		if (dev_is_pci(pn->dev)) {
 			get_device(pn->dev);
-			pci_dev = to_pci_dev(pn->dev);
-			break;
+			return to_pci_dev(pn->dev);
 		}
 	}
 
-	mutex_unlock(&adev->physical_node_lock);
-
-	return pci_dev;
+	return NULL;
 }
 EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
 
-- 
2.51.0

Re: [PATCH v2 1/4] ACPI: PCI: Use a mutex guard to simplify acpi_get_pci_dev()

Posted by Ilpo Järvinen 5 days, 5 hours ago

On Thu, 16 Jul 2026, Rafael J. Wysocki wrote:

> From: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
> 
> Use a mutex guard in acpi_get_pci_dev() for the physical_node_lock
> locking and drop local variable pci_dev that becomes redundant after
> that change.
> 
> No intentional functional impact.
> 
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> ---
> 
> v1 -> v2:
>    * Add cleanup.h include to pci_root.c (Andy)
> 
> ---
>  drivers/acpi/pci_root.c | 11 ++++-------
>  1 file changed, 4 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
> index 4c06c3ffd0cb..d0dafc38b0cf 100644
> --- a/drivers/acpi/pci_root.c
> +++ b/drivers/acpi/pci_root.c
> @@ -8,6 +8,7 @@
>  
>  #define pr_fmt(fmt) "ACPI: " fmt
>  
> +#include <linux/cleanup.h>
>  #include <linux/kernel.h>
>  #include <linux/module.h>
>  #include <linux/init.h>
> @@ -307,24 +308,20 @@ struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
>  {
>  	struct acpi_device *adev = acpi_fetch_acpi_dev(handle);
>  	struct acpi_device_physical_node *pn;
> -	struct pci_dev *pci_dev = NULL;
>  
>  	if (!adev)
>  		return NULL;
>  
> -	mutex_lock(&adev->physical_node_lock);
> +	guard(mutex)(&adev->physical_node_lock);
>  
>  	list_for_each_entry(pn, &adev->physical_node_list, node) {
>  		if (dev_is_pci(pn->dev)) {
>  			get_device(pn->dev);
> -			pci_dev = to_pci_dev(pn->dev);
> -			break;
> +			return to_pci_dev(pn->dev);
>  		}
>  	}
>  
> -	mutex_unlock(&adev->physical_node_lock);
> -
> -	return pci_dev;
> +	return NULL;
>  }
>  EXPORT_SYMBOL_GPL(acpi_get_pci_dev);

Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

-- 
 i.

Re: [PATCH v2 1/4] ACPI: PCI: Use a mutex guard to simplify acpi_get_pci_dev()

Posted by Andy Shevchenko 1 week, 1 day ago

On Thu, Jul 16, 2026 at 04:04:43PM +0200, Rafael J. Wysocki wrote:

> Use a mutex guard in acpi_get_pci_dev() for the physical_node_lock
> locking and drop local variable pci_dev that becomes redundant after
> that change.
> 
> No intentional functional impact.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>


-- 
With Best Regards,
Andy Shevchenko