[PATCH v2 4/8] ACPI: driver: Do not set acpi_device_name() unnecessarily

Rafael J. Wysocki posted 1 patch 3 weeks, 3 days ago
drivers/acpi/ac.c              |    6 ++----
drivers/acpi/acpi_memhotplug.c |    2 --
drivers/acpi/acpi_pad.c        |    2 --
drivers/acpi/acpi_processor.c  |    1 -
drivers/acpi/acpi_video.c      |   16 +++++-----------
drivers/acpi/battery.c         |    3 ---
drivers/acpi/button.c          |    7 +++----
drivers/acpi/ec.c              |    2 --
drivers/acpi/pci_link.c        |    2 --
drivers/acpi/pci_root.c        |    7 ++-----
drivers/acpi/power.c           |    2 --
drivers/acpi/sbs.c             |    1 -
drivers/acpi/sbshc.c           |    2 --
drivers/acpi/thermal.c         |    6 ++----
include/acpi/processor.h       |    1 -
15 files changed, 14 insertions(+), 46 deletions(-)
[PATCH v2 4/8] ACPI: driver: Do not set acpi_device_name() unnecessarily
Posted by Rafael J. Wysocki 3 weeks, 3 days ago
From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

ACPI drivers usually set acpi_device_name() for the given struct
acpi_device to whatever they like, but that value is never used unless
the driver itself uses it and, quite unfortunately, drivers neglect to
clear it on remove.  Some drivers use it for printing messages or
initializing the names of subordinate devices, but it is better to use
string literals for that, especially if the given one is used just once.

To eliminate unnecessary overhead related to acpi_device_name()
handling, rework multiple core ACPI device drivers to stop setting
acpi_device_name() for struct acpi_device objects manipulated
by them and use a string literal instead of it where applicable.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
 drivers/acpi/ac.c              |    6 ++----
 drivers/acpi/acpi_memhotplug.c |    2 --
 drivers/acpi/acpi_pad.c        |    2 --
 drivers/acpi/acpi_processor.c  |    1 -
 drivers/acpi/acpi_video.c      |   16 +++++-----------
 drivers/acpi/battery.c         |    3 ---
 drivers/acpi/button.c          |    7 +++----
 drivers/acpi/ec.c              |    2 --
 drivers/acpi/pci_link.c        |    2 --
 drivers/acpi/pci_root.c        |    7 ++-----
 drivers/acpi/power.c           |    2 --
 drivers/acpi/sbs.c             |    1 -
 drivers/acpi/sbshc.c           |    2 --
 drivers/acpi/thermal.c         |    6 ++----
 include/acpi/processor.h       |    1 -
 15 files changed, 14 insertions(+), 46 deletions(-)

--- a/drivers/acpi/ac.c
+++ b/drivers/acpi/ac.c
@@ -22,7 +22,6 @@
 #include <acpi/battery.h>
 
 #define ACPI_AC_CLASS			"ac_adapter"
-#define ACPI_AC_DEVICE_NAME		"AC Adapter"
 #define ACPI_AC_FILE_STATE		"state"
 #define ACPI_AC_NOTIFY_STATUS		0x80
 #define ACPI_AC_STATUS_OFFLINE		0x00
@@ -203,7 +202,6 @@ static int acpi_ac_probe(struct platform
 		return -ENOMEM;
 
 	ac->device = adev;
-	strscpy(acpi_device_name(adev), ACPI_AC_DEVICE_NAME);
 	strscpy(acpi_device_class(adev), ACPI_AC_CLASS);
 
 	platform_set_drvdata(pdev, ac);
@@ -226,8 +224,8 @@ static int acpi_ac_probe(struct platform
 		goto err_release_ac;
 	}
 
-	pr_info("%s [%s] (%s-line)\n", acpi_device_name(adev),
-		acpi_device_bid(adev), str_on_off(ac->state));
+	pr_info("AC Adapter [%s] (%s-line)\n", acpi_device_bid(adev),
+		str_on_off(ac->state));
 
 	ac->battery_nb.notifier_call = acpi_ac_battery_notify;
 	register_acpi_notifier(&ac->battery_nb);
--- a/drivers/acpi/acpi_memhotplug.c
+++ b/drivers/acpi/acpi_memhotplug.c
@@ -20,7 +20,6 @@
 
 #define ACPI_MEMORY_DEVICE_CLASS		"memory"
 #define ACPI_MEMORY_DEVICE_HID			"PNP0C80"
-#define ACPI_MEMORY_DEVICE_NAME			"Hotplug Mem Device"
 
 static const struct acpi_device_id memory_device_ids[] = {
 	{ACPI_MEMORY_DEVICE_HID, 0},
@@ -297,7 +296,6 @@ static int acpi_memory_device_add(struct
 	INIT_LIST_HEAD(&mem_device->res_list);
 	mem_device->device = device;
 	mem_device->mgid = -1;
-	sprintf(acpi_device_name(device), "%s", ACPI_MEMORY_DEVICE_NAME);
 	sprintf(acpi_device_class(device), "%s", ACPI_MEMORY_DEVICE_CLASS);
 	device->driver_data = mem_device;
 
--- a/drivers/acpi/acpi_pad.c
+++ b/drivers/acpi/acpi_pad.c
@@ -24,7 +24,6 @@
 #include <xen/xen.h>
 
 #define ACPI_PROCESSOR_AGGREGATOR_CLASS	"acpi_pad"
-#define ACPI_PROCESSOR_AGGREGATOR_DEVICE_NAME "Processor Aggregator"
 #define ACPI_PROCESSOR_AGGREGATOR_NOTIFY 0x80
 
 #define ACPI_PROCESSOR_AGGREGATOR_STATUS_SUCCESS	0
@@ -427,7 +426,6 @@ static int acpi_pad_probe(struct platfor
 {
 	struct acpi_device *adev = ACPI_COMPANION(&pdev->dev);
 
-	strscpy(acpi_device_name(adev), ACPI_PROCESSOR_AGGREGATOR_DEVICE_NAME);
 	strscpy(acpi_device_class(adev), ACPI_PROCESSOR_AGGREGATOR_CLASS);
 
 	return acpi_dev_install_notify_handler(adev, ACPI_DEVICE_NOTIFY,
--- a/drivers/acpi/acpi_processor.c
+++ b/drivers/acpi/acpi_processor.c
@@ -438,7 +438,6 @@ static int acpi_processor_add(struct acp
 	}
 
 	pr->handle = device->handle;
-	strscpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
 	strscpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
 	device->driver_data = pr;
 
--- a/drivers/acpi/acpi_video.c
+++ b/drivers/acpi/acpi_video.c
@@ -30,9 +30,6 @@
 #include <linux/uaccess.h>
 #include <linux/string_choices.h>
 
-#define ACPI_VIDEO_BUS_NAME		"Video Bus"
-#define ACPI_VIDEO_DEVICE_NAME		"Video Device"
-
 #define MAX_NAME_LEN	20
 
 MODULE_AUTHOR("Bruno Ducrot");
@@ -1144,7 +1141,6 @@ static int acpi_video_bus_get_one_device
 		return -ENOMEM;
 	}
 
-	strscpy(acpi_device_name(device), ACPI_VIDEO_DEVICE_NAME);
 	strscpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
 
 	data->device_id = device_id;
@@ -1882,7 +1878,7 @@ static int acpi_video_bus_add_notify_han
 	snprintf(video->phys, sizeof(video->phys),
 			"%s/video/input0", acpi_device_hid(video->device));
 
-	input->name = acpi_device_name(video->device);
+	input->name = "Video Bus";
 	input->phys = video->phys;
 	input->id.bustype = BUS_HOST;
 	input->id.product = 0x06;
@@ -2019,7 +2015,6 @@ static int acpi_video_bus_probe(struct a
 	auxiliary_set_drvdata(aux_dev, video);
 
 	video->device = device;
-	strscpy(acpi_device_name(device), ACPI_VIDEO_BUS_NAME);
 	strscpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
 	device->driver_data = video;
 
@@ -2041,11 +2036,10 @@ static int acpi_video_bus_probe(struct a
 	 */
 	acpi_device_fix_up_power_children(device);
 
-	pr_info("%s [%s] (multi-head: %s  rom: %s  post: %s)\n",
-	       ACPI_VIDEO_DEVICE_NAME, acpi_device_bid(device),
-	       str_yes_no(video->flags.multihead),
-	       str_yes_no(video->flags.rom),
-	       str_yes_no(video->flags.post));
+	pr_info("Video Device [%s] (multi-head: %s  rom: %s  post: %s)\n",
+		acpi_device_bid(device), str_yes_no(video->flags.multihead),
+		str_yes_no(video->flags.rom), str_yes_no(video->flags.post));
+
 	mutex_lock(&video_list_lock);
 	list_add_tail(&video->entry, &video_bus_head);
 	mutex_unlock(&video_list_lock);
--- a/drivers/acpi/battery.c
+++ b/drivers/acpi/battery.c
@@ -33,8 +33,6 @@
 #define ACPI_BATTERY_CAPACITY_VALID(capacity) \
 	((capacity) != 0 && (capacity) != ACPI_BATTERY_VALUE_UNKNOWN)
 
-#define ACPI_BATTERY_DEVICE_NAME	"Battery"
-
 /* Battery power unit: 0 means mW, 1 means mA */
 #define ACPI_BATTERY_POWER_UNIT_MA	1
 
@@ -1229,7 +1227,6 @@ static int acpi_battery_probe(struct pla
 	platform_set_drvdata(pdev, battery);
 
 	battery->device = device;
-	strscpy(acpi_device_name(device), ACPI_BATTERY_DEVICE_NAME);
 	strscpy(acpi_device_class(device), ACPI_BATTERY_CLASS);
 
 	result = devm_mutex_init(&pdev->dev, &battery->update_lock);
--- a/drivers/acpi/button.c
+++ b/drivers/acpi/button.c
@@ -558,27 +558,26 @@ static int acpi_button_probe(struct plat
 		goto err_free_button;
 	}
 
-	name = acpi_device_name(device);
 	class = acpi_device_class(device);
 
 	if (!strcmp(hid, ACPI_BUTTON_HID_POWER) ||
 	    !strcmp(hid, ACPI_BUTTON_HID_POWERF)) {
 		button->type = ACPI_BUTTON_TYPE_POWER;
 		handler = acpi_button_notify;
-		strscpy(name, ACPI_BUTTON_DEVICE_NAME_POWER, MAX_ACPI_DEVICE_NAME_LEN);
+		name = ACPI_BUTTON_DEVICE_NAME_POWER;
 		sprintf(class, "%s/%s",
 			ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_POWER);
 	} else if (!strcmp(hid, ACPI_BUTTON_HID_SLEEP) ||
 		   !strcmp(hid, ACPI_BUTTON_HID_SLEEPF)) {
 		button->type = ACPI_BUTTON_TYPE_SLEEP;
 		handler = acpi_button_notify;
-		strscpy(name, ACPI_BUTTON_DEVICE_NAME_SLEEP, MAX_ACPI_DEVICE_NAME_LEN);
+		name = ACPI_BUTTON_DEVICE_NAME_SLEEP;
 		sprintf(class, "%s/%s",
 			ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_SLEEP);
 	} else if (!strcmp(hid, ACPI_BUTTON_HID_LID)) {
 		button->type = ACPI_BUTTON_TYPE_LID;
 		handler = acpi_lid_notify;
-		strscpy(name, ACPI_BUTTON_DEVICE_NAME_LID, MAX_ACPI_DEVICE_NAME_LEN);
+		name = ACPI_BUTTON_DEVICE_NAME_LID;
 		sprintf(class, "%s/%s",
 			ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_LID);
 		input->open = acpi_lid_input_open;
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -36,7 +36,6 @@
 #include "internal.h"
 
 #define ACPI_EC_CLASS			"embedded_controller"
-#define ACPI_EC_DEVICE_NAME		"Embedded Controller"
 
 /* EC status register */
 #define ACPI_EC_FLAG_OBF	0x01	/* Output buffer full */
@@ -1681,7 +1680,6 @@ static int acpi_ec_probe(struct platform
 	struct acpi_ec *ec;
 	int ret;
 
-	strscpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 	strscpy(acpi_device_class(device), ACPI_EC_CLASS);
 
 	if (boot_ec && (boot_ec->handle == device->handle ||
--- a/drivers/acpi/pci_link.c
+++ b/drivers/acpi/pci_link.c
@@ -30,7 +30,6 @@
 #include "internal.h"
 
 #define ACPI_PCI_LINK_CLASS		"pci_irq_routing"
-#define ACPI_PCI_LINK_DEVICE_NAME	"PCI Interrupt Link"
 #define ACPI_PCI_LINK_MAX_POSSIBLE	16
 
 static int acpi_pci_link_add(struct acpi_device *device,
@@ -725,7 +724,6 @@ static int acpi_pci_link_add(struct acpi
 		return -ENOMEM;
 
 	link->device = device;
-	strscpy(acpi_device_name(device), ACPI_PCI_LINK_DEVICE_NAME);
 	strscpy(acpi_device_class(device), ACPI_PCI_LINK_CLASS);
 	device->driver_data = link;
 
--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -25,7 +25,6 @@
 #include "internal.h"
 
 #define ACPI_PCI_ROOT_CLASS		"pci_bridge"
-#define ACPI_PCI_ROOT_DEVICE_NAME	"PCI Root Bridge"
 static int acpi_pci_root_add(struct acpi_device *device,
 			     const struct acpi_device_id *not_used);
 static void acpi_pci_root_remove(struct acpi_device *device);
@@ -689,7 +688,6 @@ static int acpi_pci_root_add(struct acpi
 
 	root->device = device;
 	root->segment = segment & 0xFFFF;
-	strscpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
 	strscpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
 	device->driver_data = root;
 
@@ -698,9 +696,8 @@ static int acpi_pci_root_add(struct acpi
 		goto end;
 	}
 
-	pr_info("%s [%s] (domain %04x %pR)\n",
-	       acpi_device_name(device), acpi_device_bid(device),
-	       root->segment, &root->secondary);
+	pr_info("PCI Root Bridge [%s] (domain %04x %pR)\n",
+		acpi_device_bid(device), root->segment, &root->secondary);
 
 	root->mcfg_addr = acpi_pci_root_get_mcfg_addr(handle);
 
--- a/drivers/acpi/power.c
+++ b/drivers/acpi/power.c
@@ -38,7 +38,6 @@
 #include "internal.h"
 
 #define ACPI_POWER_CLASS		"power_resource"
-#define ACPI_POWER_DEVICE_NAME		"Power Resource"
 #define ACPI_POWER_RESOURCE_STATE_OFF	0x00
 #define ACPI_POWER_RESOURCE_STATE_ON	0x01
 #define ACPI_POWER_RESOURCE_STATE_UNKNOWN 0xFF
@@ -955,7 +954,6 @@ struct acpi_device *acpi_add_power_resou
 	mutex_init(&resource->resource_lock);
 	INIT_LIST_HEAD(&resource->list_node);
 	INIT_LIST_HEAD(&resource->dependents);
-	strscpy(acpi_device_name(device), ACPI_POWER_DEVICE_NAME);
 	strscpy(acpi_device_class(device), ACPI_POWER_CLASS);
 	device->power.state = ACPI_STATE_UNKNOWN;
 	device->flags.match_driver = true;
--- a/drivers/acpi/sbs.c
+++ b/drivers/acpi/sbs.c
@@ -648,7 +648,6 @@ static int acpi_sbs_probe(struct platfor
 
 	sbs->hc = dev_get_drvdata(pdev->dev.parent);
 	sbs->device = device;
-	strscpy(acpi_device_name(device), ACPI_SBS_DEVICE_NAME);
 	strscpy(acpi_device_class(device), ACPI_SBS_CLASS);
 
 	result = acpi_charger_add(sbs);
--- a/drivers/acpi/sbshc.c
+++ b/drivers/acpi/sbshc.c
@@ -19,7 +19,6 @@
 #include "internal.h"
 
 #define ACPI_SMB_HC_CLASS	"smbus_host_ctl"
-#define ACPI_SMB_HC_DEVICE_NAME	"ACPI SMBus HC"
 
 struct acpi_smb_hc {
 	struct acpi_ec *ec;
@@ -251,7 +250,6 @@ static int acpi_smbus_hc_probe(struct pl
 		return -EIO;
 	}
 
-	strscpy(acpi_device_name(device), ACPI_SMB_HC_DEVICE_NAME);
 	strscpy(acpi_device_class(device), ACPI_SMB_HC_CLASS);
 
 	hc = kzalloc_obj(struct acpi_smb_hc);
--- a/drivers/acpi/thermal.c
+++ b/drivers/acpi/thermal.c
@@ -35,7 +35,6 @@
 #include "internal.h"
 
 #define ACPI_THERMAL_CLASS		"thermal_zone"
-#define ACPI_THERMAL_DEVICE_NAME	"Thermal Zone"
 #define ACPI_THERMAL_NOTIFY_TEMPERATURE	0x80
 #define ACPI_THERMAL_NOTIFY_THRESHOLDS	0x81
 #define ACPI_THERMAL_NOTIFY_DEVICES	0x82
@@ -800,7 +799,6 @@ static int acpi_thermal_probe(struct pla
 
 	tz->device = device;
 	strscpy(tz->name, device->pnp.bus_id);
-	strscpy(acpi_device_name(device), ACPI_THERMAL_DEVICE_NAME);
 	strscpy(acpi_device_class(device), ACPI_THERMAL_CLASS);
 
 	acpi_thermal_aml_dependency_fix(tz);
@@ -879,8 +877,8 @@ static int acpi_thermal_probe(struct pla
 	mutex_init(&tz->thermal_check_lock);
 	INIT_WORK(&tz->thermal_check_work, acpi_thermal_check_fn);
 
-	pr_info("%s [%s] (%ld C)\n", acpi_device_name(device),
-		acpi_device_bid(device), deci_kelvin_to_celsius(tz->temp_dk));
+	pr_info("Thermal Zone [%s] (%ld C)\n", acpi_device_bid(device),
+		deci_kelvin_to_celsius(tz->temp_dk));
 
 	result = acpi_dev_install_notify_handler(device, ACPI_DEVICE_NOTIFY,
 						 acpi_thermal_notify, tz);
--- a/include/acpi/processor.h
+++ b/include/acpi/processor.h
@@ -15,7 +15,6 @@
 #include <asm/acpi.h>
 
 #define ACPI_PROCESSOR_CLASS		"processor"
-#define ACPI_PROCESSOR_DEVICE_NAME	"Processor"
 #define ACPI_PROCESSOR_DEVICE_HID	"ACPI0007"
 #define ACPI_PROCESSOR_CONTAINER_HID	"ACPI0010"