linux-kernel - [PATCH v1 2/2] gpiolib: acpi: Make sure we fill struct acpi_gpio

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Message-ID: <20250409132942.2550719-3-andriy.shevchenko@linux.intel.com>
Date: Wed,  9 Apr 2025 16:27:54 +0300
From: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
To: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
	linux-gpio@...r.kernel.org,
	linux-acpi@...r.kernel.org,
	linux-kernel@...r.kernel.org
Cc: Mika Westerberg <westeri@...nel.org>,
	Linus Walleij <linus.walleij@...aro.org>,
	Bartosz Golaszewski <brgl@...ev.pl>,
	Kees Bakker <kees@...erbout.nl>
Subject: [PATCH v1 2/2] gpiolib: acpi: Make sure we fill struct acpi_gpio_info

The previous refactoring missed the filling of the struct acpi_gpio_info
and that's how the lot of the code got eliminated. Restore those pieces
by passing the pointer all down in the call stack.

With this, the code grows by ~6%, but in conjunction with the previous
refactoring it still gives -387 bytes

add/remove: 2/0 grow/shrink: 5/1 up/down: 852/-35 (817)
Function                                     old     new   delta
acpi_dev_gpio_irq_wake_get_by                129     695    +566
acpi_find_gpio                               216     354    +138
acpi_find_gpio.__UNIQUE_ID_ddebug504           -      56     +56
acpi_dev_gpio_irq_wake_get_by.__UNIQUE_ID_ddebug506       -      56     +56
acpi_populate_gpio_lookup                    536     548     +12
acpi_gpio_property_lookup                    414     426     +12
acpi_get_gpiod_by_index                      307     319     +12
__acpi_find_gpio                             638     603     -35
Total: Before=14154, After=14971, chg +5.77%

As a positive side effect, it improves memory footprint for
struct acpi_gpio_lookup. `pahole` difference before and after:

-       /* size: 64, cachelines: 1, members: 4 */
-       /* member types with holes: 1, total: 1 */

+       /* size: 32, cachelines: 1, members: 4 */

Reported-by: Kees Bakker <kees@...erbout.nl>
Closes: https://lore.kernel.org/r/9715c8dd-38df-48fd-a9d1-7a78163dc989@ijzerbout.nl
Fixes: 8b4f52ef7a41 ("gpiolib: acpi: Deduplicate some code in __acpi_find_gpio()")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
---
 drivers/gpio/gpiolib-acpi.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c
index 5b6344f0d065..2ac9c7b31908 100644
--- a/drivers/gpio/gpiolib-acpi.c
+++ b/drivers/gpio/gpiolib-acpi.c
@@ -742,8 +742,8 @@ static int acpi_gpio_update_gpiod_lookup_flags(unsigned long *lookupflags,
 }
 
 struct acpi_gpio_lookup {
-	struct acpi_gpio_info info;
 	struct acpi_gpio_params params;
+	struct acpi_gpio_info *info;
 	struct gpio_desc *desc;
 	int n;
 };
@@ -752,7 +752,7 @@ static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data)
 {
 	struct acpi_gpio_lookup *lookup = data;
 	struct acpi_gpio_params *params = &lookup->params;
-	struct acpi_gpio_info *info = &lookup->info;
+	struct acpi_gpio_info *info = lookup->info;
 
 	if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
 		return 1;
@@ -806,7 +806,7 @@ static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data)
 
 static int acpi_gpio_resource_lookup(struct acpi_gpio_lookup *lookup)
 {
-	struct acpi_gpio_info *info = &lookup->info;
+	struct acpi_gpio_info *info = lookup->info;
 	struct acpi_device *adev = info->adev;
 	struct list_head res_list;
 	int ret;
@@ -832,7 +832,7 @@ static int acpi_gpio_property_lookup(struct fwnode_handle *fwnode, const char *p
 {
 	struct fwnode_reference_args args;
 	struct acpi_gpio_params *params = &lookup->params;
-	struct acpi_gpio_info *info = &lookup->info;
+	struct acpi_gpio_info *info = lookup->info;
 	unsigned int index = params->crs_entry_index;
 	unsigned int quirks = 0;
 	int ret;
@@ -893,8 +893,8 @@ static int acpi_gpio_property_lookup(struct fwnode_handle *fwnode, const char *p
 static int acpi_get_gpiod_by_index(struct acpi_device *adev, const char *propname,
 				   struct acpi_gpio_lookup *lookup)
 {
-	struct acpi_gpio_info *info = &lookup->info;
 	struct acpi_gpio_params *params = &lookup->params;
+	struct acpi_gpio_info *info = lookup->info;
 	int ret;
 
 	if (propname) {
@@ -975,6 +975,7 @@ __acpi_find_gpio(struct fwnode_handle *fwnode, const char *con_id, unsigned int
 
 	memset(&lookup, 0, sizeof(lookup));
 	lookup.params.crs_entry_index = idx;
+	lookup.info = info;
 
 	/* Try first from _DSD */
 	for_each_gpio_property_name(propname, con_id) {
-- 
2.47.2