[PATCH 0/6] Deduplicate string exposure in sysfs

[PATCH 0/6] Deduplicate string exposure in sysfs

[Lukas Wunner]

Introduce a generic ->show() callback to expose a string as a device
attribute in sysfs.  Deduplicate various identical callbacks across
the tree.

Result:  Minus 216 LoC, minus 1576 bytes vmlinux size (x86_64 allyesconfig).

This is a byproduct of my upcoming PCI device authentication v2 patches.


Lukas Wunner (6):
  driver core: Add device_show_string() helper for sysfs attributes
  hwmon: Use device_show_string() helper for sysfs attributes
  IB/qib: Use device_show_string() helper for sysfs attributes
  perf: Use device_show_string() helper for sysfs attributes
  platform/x86: Use device_show_string() helper for sysfs attributes
  scsi: Use device_show_string() helper for sysfs attributes

 arch/powerpc/perf/hv-24x7.c              | 10 ----
 arch/x86/events/intel/core.c             | 13 ++---
 drivers/base/core.c                      |  9 ++++
 drivers/hwmon/i5k_amb.c                  | 15 ++----
 drivers/hwmon/ibmpex.c                   | 14 ++----
 drivers/infiniband/hw/qib/qib.h          |  1 -
 drivers/infiniband/hw/qib/qib_driver.c   |  6 ---
 drivers/infiniband/hw/qib/qib_sysfs.c    | 10 +---
 drivers/perf/alibaba_uncore_drw_pmu.c    | 12 +----
 drivers/perf/arm-cci.c                   | 12 +----
 drivers/perf/arm-ccn.c                   | 11 +----
 drivers/perf/arm_cspmu/arm_cspmu.c       | 10 ----
 drivers/perf/arm_cspmu/arm_cspmu.h       |  7 +--
 drivers/perf/arm_dsu_pmu.c               | 11 +----
 drivers/perf/cxl_pmu.c                   | 13 +----
 drivers/perf/hisilicon/hisi_pcie_pmu.c   | 13 +----
 drivers/perf/hisilicon/hisi_uncore_pmu.c | 14 ------
 drivers/perf/hisilicon/hisi_uncore_pmu.h |  4 +-
 drivers/perf/hisilicon/hns3_pmu.c        | 12 +----
 drivers/perf/qcom_l3_pmu.c               | 11 +----
 drivers/perf/xgene_pmu.c                 | 11 +----
 drivers/platform/x86/asus-wmi.c          | 62 ++++++------------------
 drivers/platform/x86/thinkpad_acpi.c     | 10 +---
 drivers/platform/x86/toshiba_acpi.c      |  9 +---
 drivers/scsi/bfa/bfad_attr.c             | 28 +++--------
 drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c | 11 +----
 drivers/scsi/mvsas/mv_init.c             | 10 +---
 drivers/scsi/qla2xxx/qla_attr.c          | 11 +----
 drivers/scsi/smartpqi/smartpqi_init.c    | 11 ++---
 include/linux/device.h                   | 15 ++++++
 30 files changed, 85 insertions(+), 301 deletions(-)

-- 
2.43.0

[PATCH 2/6] hwmon: Use device_show_string() helper for sysfs attributes

[Lukas Wunner]

Deduplicate sysfs ->show() callbacks which expose a string at a static
memory location.  Use the newly introduced device_show_string() helper
in the driver core instead by declaring those sysfs attributes with
DEVICE_STRING_ATTR_RO().

No functional change intended.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
---
 drivers/hwmon/i5k_amb.c | 15 ++++-----------
 drivers/hwmon/ibmpex.c  | 14 ++++----------
 2 files changed, 8 insertions(+), 21 deletions(-)

diff --git a/drivers/hwmon/i5k_amb.c b/drivers/hwmon/i5k_amb.c
index ff48913fe6bf..02f5d35dd319 100644
--- a/drivers/hwmon/i5k_amb.c
+++ b/drivers/hwmon/i5k_amb.c
@@ -101,14 +101,7 @@ struct i5k_amb_data {
 	unsigned int num_attrs;
 };
 
-static ssize_t name_show(struct device *dev, struct device_attribute *devattr,
-			 char *buf)
-{
-	return sprintf(buf, "%s\n", DRVNAME);
-}
-
-
-static DEVICE_ATTR_RO(name);
+static DEVICE_STRING_ATTR_RO(name, 0444, DRVNAME);
 
 static struct platform_device *amb_pdev;
 
@@ -373,7 +366,7 @@ static int i5k_amb_hwmon_init(struct platform_device *pdev)
 		}
 	}
 
-	res = device_create_file(&pdev->dev, &dev_attr_name);
+	res = device_create_file(&pdev->dev, &dev_attr_name.attr);
 	if (res)
 		goto exit_remove;
 
@@ -386,7 +379,7 @@ static int i5k_amb_hwmon_init(struct platform_device *pdev)
 	return res;
 
 exit_remove:
-	device_remove_file(&pdev->dev, &dev_attr_name);
+	device_remove_file(&pdev->dev, &dev_attr_name.attr);
 	for (i = 0; i < data->num_attrs; i++)
 		device_remove_file(&pdev->dev, &data->attrs[i].s_attr.dev_attr);
 	kfree(data->attrs);
@@ -561,7 +554,7 @@ static void i5k_amb_remove(struct platform_device *pdev)
 	struct i5k_amb_data *data = platform_get_drvdata(pdev);
 
 	hwmon_device_unregister(data->hwmon_dev);
-	device_remove_file(&pdev->dev, &dev_attr_name);
+	device_remove_file(&pdev->dev, &dev_attr_name.attr);
 	for (i = 0; i < data->num_attrs; i++)
 		device_remove_file(&pdev->dev, &data->attrs[i].s_attr.dev_attr);
 	kfree(data->attrs);
diff --git a/drivers/hwmon/ibmpex.c b/drivers/hwmon/ibmpex.c
index db066b368918..228c5f6c6f38 100644
--- a/drivers/hwmon/ibmpex.c
+++ b/drivers/hwmon/ibmpex.c
@@ -256,12 +256,7 @@ static struct ibmpex_bmc_data *get_bmc_data(int iface)
 	return NULL;
 }
 
-static ssize_t name_show(struct device *dev, struct device_attribute *devattr,
-			 char *buf)
-{
-	return sprintf(buf, "%s\n", DRVNAME);
-}
-static SENSOR_DEVICE_ATTR_RO(name, name, 0);
+static DEVICE_STRING_ATTR_RO(name, 0444, DRVNAME);
 
 static ssize_t ibmpex_show_sensor(struct device *dev,
 				  struct device_attribute *devattr,
@@ -415,8 +410,7 @@ static int ibmpex_find_sensors(struct ibmpex_bmc_data *data)
 	if (err)
 		goto exit_remove;
 
-	err = device_create_file(data->bmc_device,
-			&sensor_dev_attr_name.dev_attr);
+	err = device_create_file(data->bmc_device, &dev_attr_name.attr);
 	if (err)
 		goto exit_remove;
 
@@ -425,7 +419,7 @@ static int ibmpex_find_sensors(struct ibmpex_bmc_data *data)
 exit_remove:
 	device_remove_file(data->bmc_device,
 			   &sensor_dev_attr_reset_high_low.dev_attr);
-	device_remove_file(data->bmc_device, &sensor_dev_attr_name.dev_attr);
+	device_remove_file(data->bmc_device, &dev_attr_name.attr);
 	for (i = 0; i < data->num_sensors; i++)
 		for (j = 0; j < PEX_NUM_SENSOR_FUNCS; j++) {
 			if (!data->sensors[i].attr[j].dev_attr.attr.name)
@@ -516,7 +510,7 @@ static void ibmpex_bmc_delete(struct ibmpex_bmc_data *data)
 
 	device_remove_file(data->bmc_device,
 			   &sensor_dev_attr_reset_high_low.dev_attr);
-	device_remove_file(data->bmc_device, &sensor_dev_attr_name.dev_attr);
+	device_remove_file(data->bmc_device, &dev_attr_name.attr);
 	for (i = 0; i < data->num_sensors; i++)
 		for (j = 0; j < PEX_NUM_SENSOR_FUNCS; j++) {
 			if (!data->sensors[i].attr[j].dev_attr.attr.name)
-- 
2.43.0

Re: [PATCH 2/6] hwmon: Use device_show_string() helper for sysfs attributes

[Guenter Roeck]

On Sat, Apr 20, 2024 at 10:00:02PM +0200, Lukas Wunner wrote:
> Deduplicate sysfs ->show() callbacks which expose a string at a static
> memory location.  Use the newly introduced device_show_string() helper
> in the driver core instead by declaring those sysfs attributes with
> DEVICE_STRING_ATTR_RO().
> 
> No functional change intended.
> 
> Signed-off-by: Lukas Wunner <lukas@wunner.de>

Acked-by: Guenter Roeck <linux@roeck-us.net>

Guenter

Re: [PATCH 0/6] Deduplicate string exposure in sysfs

[Lukas Wunner]

Dear Greg,

On Sat, Apr 20, 2024 at 10:00:00PM +0200, Lukas Wunner wrote:
> Introduce a generic ->show() callback to expose a string as a device
> attribute in sysfs.  Deduplicate various identical callbacks across
> the tree.
> 
> Result:  Minus 216 LoC, minus 1576 bytes vmlinux size (x86_64 allyesconfig).
> 
> This is a byproduct of my upcoming PCI device authentication v2 patches.
> 
> 
> Lukas Wunner (6):
>   driver core: Add device_show_string() helper for sysfs attributes
>   hwmon: Use device_show_string() helper for sysfs attributes
>   IB/qib: Use device_show_string() helper for sysfs attributes
>   perf: Use device_show_string() helper for sysfs attributes
>   platform/x86: Use device_show_string() helper for sysfs attributes
>   scsi: Use device_show_string() helper for sysfs attributes

This series hasn't been applied to driver-core-next AFAICS and the
merge window is drawing closer.

So far only patches 1, 2 and 5 have been ack'ed by the respective
subsystem maintainers.  If the missing acks are the reason it hasn't
been applied, would it be possibe to apply only 1, 2 and 5?

I would then resubmit the other ones individually to the subsystem
maintainers in the next cycle.

Thanks!

Lukas

Re: [PATCH 0/6] Deduplicate string exposure in sysfs

[Greg Kroah-Hartman]

On Sat, May 04, 2024 at 04:31:42PM +0200, Lukas Wunner wrote:
> Dear Greg,
> 
> On Sat, Apr 20, 2024 at 10:00:00PM +0200, Lukas Wunner wrote:
> > Introduce a generic ->show() callback to expose a string as a device
> > attribute in sysfs.  Deduplicate various identical callbacks across
> > the tree.
> > 
> > Result:  Minus 216 LoC, minus 1576 bytes vmlinux size (x86_64 allyesconfig).
> > 
> > This is a byproduct of my upcoming PCI device authentication v2 patches.
> > 
> > 
> > Lukas Wunner (6):
> >   driver core: Add device_show_string() helper for sysfs attributes
> >   hwmon: Use device_show_string() helper for sysfs attributes
> >   IB/qib: Use device_show_string() helper for sysfs attributes
> >   perf: Use device_show_string() helper for sysfs attributes
> >   platform/x86: Use device_show_string() helper for sysfs attributes
> >   scsi: Use device_show_string() helper for sysfs attributes
> 
> This series hasn't been applied to driver-core-next AFAICS and the
> merge window is drawing closer.
> 
> So far only patches 1, 2 and 5 have been ack'ed by the respective
> subsystem maintainers.  If the missing acks are the reason it hasn't
> been applied, would it be possibe to apply only 1, 2 and 5?
> 
> I would then resubmit the other ones individually to the subsystem
> maintainers in the next cycle.

I'll just pick it up now, thanks!

greg k-h