[PATCH v3 12/12] gpio: rockchip: replace mutex_lock() with guard()

Ye Zhang posted 12 patches 1 year, 3 months ago
Only 8 patches received!
There is a newer version of this series
[PATCH v3 12/12] gpio: rockchip: replace mutex_lock() with guard()
Posted by Ye Zhang 1 year, 3 months ago
Replacing mutex_lock with guard() simplifies the code and helps avoid
deadlocks.

Signed-off-by: Ye Zhang <ye.zhang@rock-chips.com>
---
 drivers/gpio/gpio-rockchip.c | 14 +++++---------
 1 file changed, 5 insertions(+), 9 deletions(-)

diff --git a/drivers/gpio/gpio-rockchip.c b/drivers/gpio/gpio-rockchip.c
index 73e57efb46fc..d5c57617fc86 100644
--- a/drivers/gpio/gpio-rockchip.c
+++ b/drivers/gpio/gpio-rockchip.c
@@ -765,20 +765,19 @@ static int rockchip_gpio_probe(struct platform_device *pdev)
 		}
 	}
 
-	ret = rockchip_get_bank_data(bank);
-	if (ret)
-		goto err_disabled_clk;
-
 	/*
 	 * Prevent clashes with a deferred output setting
 	 * being added right at this moment.
 	 */
-	mutex_lock(&bank->deferred_lock);
+	guard(mutex)(&bank->deferred_lock);
+	ret = rockchip_get_bank_data(bank);
+	if (ret)
+		goto err_disabled_clk;
 
 	ret = rockchip_gpiolib_register(bank);
 	if (ret) {
 		dev_err(bank->dev, "Failed to register gpio %d\n", ret);
-		goto err_unlock;
+		goto err_disabled_clk;
 	}
 
 	while (!list_empty(&bank->deferred_pins)) {
@@ -805,14 +804,11 @@ static int rockchip_gpio_probe(struct platform_device *pdev)
 		kfree(cfg);
 	}
 
-	mutex_unlock(&bank->deferred_lock);
 
 	platform_set_drvdata(pdev, bank);
 	dev_info(dev, "probed %pOF\n", np);
 
 	return 0;
-err_unlock:
-	mutex_unlock(&bank->deferred_lock);
 err_disabled_clk:
 	if (bank->manual_clk_release)
 		clk_disable_unprepare(bank->clk);
-- 
2.34.1
Re: [PATCH v3 12/12] gpio: rockchip: replace mutex_lock() with guard()
Posted by Christophe JAILLET 1 year, 3 months ago
Le 03/09/2024 à 09:36, Ye Zhang a écrit :
> Replacing mutex_lock with guard() simplifies the code and helps avoid
> deadlocks.
> 
> Signed-off-by: Ye Zhang <ye.zhang@rock-chips.com>
> ---
>   drivers/gpio/gpio-rockchip.c | 14 +++++---------
>   1 file changed, 5 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/gpio/gpio-rockchip.c b/drivers/gpio/gpio-rockchip.c
> index 73e57efb46fc..d5c57617fc86 100644
> --- a/drivers/gpio/gpio-rockchip.c
> +++ b/drivers/gpio/gpio-rockchip.c
> @@ -765,20 +765,19 @@ static int rockchip_gpio_probe(struct platform_device *pdev)
>   		}
>   	}
>   
> -	ret = rockchip_get_bank_data(bank);
> -	if (ret)
> -		goto err_disabled_clk;
> -
>   	/*
>   	 * Prevent clashes with a deferred output setting
>   	 * being added right at this moment.
>   	 */
> -	mutex_lock(&bank->deferred_lock);
> +	guard(mutex)(&bank->deferred_lock);
> +	ret = rockchip_get_bank_data(bank);

rockchip_get_bank_data() was out of the lock before, now it is inside.

It looks ok, but is it on purpose? If so, maybe it could be mentioned or 
explained why in the changelog ?

CJ

> +	if (ret)
> +		goto err_disabled_clk;
>   
>   	ret = rockchip_gpiolib_register(bank);
>   	if (ret) {
>   		dev_err(bank->dev, "Failed to register gpio %d\n", ret);
> -		goto err_unlock;
> +		goto err_disabled_clk;
>   	}
>   
>   	while (!list_empty(&bank->deferred_pins)) {
> @@ -805,14 +804,11 @@ static int rockchip_gpio_probe(struct platform_device *pdev)
>   		kfree(cfg);
>   	}
>   
> -	mutex_unlock(&bank->deferred_lock);
>   
>   	platform_set_drvdata(pdev, bank);
>   	dev_info(dev, "probed %pOF\n", np);
>   
>   	return 0;
> -err_unlock:
> -	mutex_unlock(&bank->deferred_lock);
>   err_disabled_clk:
>   	if (bank->manual_clk_release)
>   		clk_disable_unprepare(bank->clk);

Re: [PATCH v3 12/12] gpio: rockchip: replace mutex_lock() with guard()
Posted by Andy Shevchenko 1 year, 3 months ago
On Tue, Sep 03, 2024 at 03:36:49PM +0800, Ye Zhang wrote:
> Replacing mutex_lock with guard() simplifies the code and helps avoid

mutex_lock()

avoiding

> deadlocks.

...

> --- a/drivers/gpio/gpio-rockchip.c
> +++ b/drivers/gpio/gpio-rockchip.c

+ cleanup.h

...

>  	}
> -	mutex_lock(&bank->deferred_lock);
> +	guard(mutex)(&bank->deferred_lock);

Make it surrounded by blank lines.

> +	ret = rockchip_get_bank_data(bank);
> +	if (ret)
> +		goto err_disabled_clk;

-- 
With Best Regards,
Andy Shevchenko