linux-kernel - [RFC PATCH] gpiolib: remove extra

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Date: Tue, 19 Dec 2023 21:11:02 +0100
From: Bartosz Golaszewski <brgl@...ev.pl>
To: Linus Walleij <linus.walleij@...aro.org>,
	Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
	Kent Gibson <warthog618@...il.com>
Cc: linux-gpio@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	Bartosz Golaszewski <bartosz.golaszewski@...aro.org>
Subject: [RFC PATCH] gpiolib: remove extra_checks

From: Bartosz Golaszewski <bartosz.golaszewski@...aro.org>

extra_checks is only used in a few places. It also depends on
a non-standard DEBUG define one needs to add to the source file. The
overhead of removing it should be minimal (we already use pure
might_sleep() in the code anyway) so drop it.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@...aro.org>
---
 drivers/gpio/gpiolib.c | 31 +++++++++----------------------
 1 file changed, 9 insertions(+), 22 deletions(-)

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index c9ca809b55de..837e9919bf07 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -47,19 +47,6 @@
  * GPIOs can sometimes cost only an instruction or two per bit.
  */
 
-
-/* When debugging, extend minimal trust to callers and platform code.
- * Also emit diagnostic messages that may help initial bringup, when
- * board setup or driver bugs are most common.
- *
- * Otherwise, minimize overhead in what may be bitbanging codepaths.
- */
-#ifdef	DEBUG
-#define	extra_checks	1
-#else
-#define	extra_checks	0
-#endif
-
 /* Device and char device-related information */
 static DEFINE_IDA(gpio_ida);
 static dev_t gpio_devt;
@@ -2351,7 +2338,7 @@ void gpiod_free(struct gpio_desc *desc)
 		return;
 
 	if (!gpiod_free_commit(desc))
-		WARN_ON(extra_checks);
+		WARN_ON(1);
 
 	module_put(desc->gdev->owner);
 	gpio_device_put(desc->gdev);
@@ -3729,7 +3716,7 @@ EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent);
  */
 int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc)
 {
-	might_sleep_if(extra_checks);
+	might_sleep();
 	VALIDATE_DESC(desc);
 	return gpiod_get_raw_value_commit(desc);
 }
@@ -3748,7 +3735,7 @@ int gpiod_get_value_cansleep(const struct gpio_desc *desc)
 {
 	int value;
 
-	might_sleep_if(extra_checks);
+	might_sleep();
 	VALIDATE_DESC(desc);
 	value = gpiod_get_raw_value_commit(desc);
 	if (value < 0)
@@ -3779,7 +3766,7 @@ int gpiod_get_raw_array_value_cansleep(unsigned int array_size,
 				       struct gpio_array *array_info,
 				       unsigned long *value_bitmap)
 {
-	might_sleep_if(extra_checks);
+	might_sleep();
 	if (!desc_array)
 		return -EINVAL;
 	return gpiod_get_array_value_complex(true, true, array_size,
@@ -3805,7 +3792,7 @@ int gpiod_get_array_value_cansleep(unsigned int array_size,
 				   struct gpio_array *array_info,
 				   unsigned long *value_bitmap)
 {
-	might_sleep_if(extra_checks);
+	might_sleep();
 	if (!desc_array)
 		return -EINVAL;
 	return gpiod_get_array_value_complex(false, true, array_size,
@@ -3826,7 +3813,7 @@ EXPORT_SYMBOL_GPL(gpiod_get_array_value_cansleep);
  */
 void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value)
 {
-	might_sleep_if(extra_checks);
+	might_sleep();
 	VALIDATE_DESC_VOID(desc);
 	gpiod_set_raw_value_commit(desc, value);
 }
@@ -3844,7 +3831,7 @@ EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep);
  */
 void gpiod_set_value_cansleep(struct gpio_desc *desc, int value)
 {
-	might_sleep_if(extra_checks);
+	might_sleep();
 	VALIDATE_DESC_VOID(desc);
 	gpiod_set_value_nocheck(desc, value);
 }
@@ -3867,7 +3854,7 @@ int gpiod_set_raw_array_value_cansleep(unsigned int array_size,
 				       struct gpio_array *array_info,
 				       unsigned long *value_bitmap)
 {
-	might_sleep_if(extra_checks);
+	might_sleep();
 	if (!desc_array)
 		return -EINVAL;
 	return gpiod_set_array_value_complex(true, true, array_size, desc_array,
@@ -3909,7 +3896,7 @@ int gpiod_set_array_value_cansleep(unsigned int array_size,
 				   struct gpio_array *array_info,
 				   unsigned long *value_bitmap)
 {
-	might_sleep_if(extra_checks);
+	might_sleep();
 	if (!desc_array)
 		return -EINVAL;
 	return gpiod_set_array_value_complex(false, true, array_size,
-- 
2.40.1