Commit 11067f50 authored by Bartosz Golaszewski's avatar Bartosz Golaszewski
Browse files

gpiolib: read descriptor flags once in gpiolib_dbg_show() 

For consistency with most other code that can access requested
descriptors: read the flags once atomically and then test individual
bits from the helper variable. This avoids any potential discrepancies
should flags change during the debug print.

Link: https://lore.kernel.org/r/20250215100847.30136-1-brgl@bgdev.pl


Signed-off-by: default avatarBartosz Golaszewski <bartosz.golaszewski@linaro.org>
parent e623c430

drivers/gpio/gpiolib.c

+6 −4
Original line number Diff line number Diff line
@@ -5111,6 +5111,7 @@ static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev) 
	unsigned int gpio = gdev->base;

	struct gpio_desc *desc;

	struct gpio_chip *gc;

	unsigned long flags;

	int value;



	guard(srcu)(&gdev->srcu);
@@ -5123,12 +5124,13 @@ static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev) 


	for_each_gpio_desc(gc, desc) {

		guard(srcu)(&desc->gdev->desc_srcu);

		is_irq = test_bit(FLAG_USED_AS_IRQ, &desc->flags);

		if (is_irq || test_bit(FLAG_REQUESTED, &desc->flags)) {

		flags = READ_ONCE(desc->flags);

		is_irq = test_bit(FLAG_USED_AS_IRQ, &flags);

		if (is_irq || test_bit(FLAG_REQUESTED, &flags)) {

			gpiod_get_direction(desc);

			is_out = test_bit(FLAG_IS_OUT, &desc->flags);

			is_out = test_bit(FLAG_IS_OUT, &flags);

			value = gpio_chip_get_value(gc, desc);

			active_low = test_bit(FLAG_ACTIVE_LOW, &desc->flags);

			active_low = test_bit(FLAG_ACTIVE_LOW, &flags);

			seq_printf(s, " gpio-%-3u (%-20.20s|%-20.20s) %s %s %s%s\n",

				   gpio, desc->name ?: "", gpiod_get_label(desc),

				   is_out ? "out" : "in ",