From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from bh-25.webhostbox.net ([208.91.199.152]:33775 "EHLO bh-25.webhostbox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932449AbcKYSW7 (ORCPT ); Fri, 25 Nov 2016 13:22:59 -0500 From: Guenter Roeck To: Hardware Monitoring Cc: Jean Delvare , Guenter Roeck Subject: [PATCH] hwmon: (core) Simplify sysfs attribute name allocation Date: Fri, 25 Nov 2016 10:22:25 -0800 Message-Id: <1480098145-23528-1-git-send-email-linux@roeck-us.net> Sender: linux-hwmon-owner@vger.kernel.org List-Id: linux-hwmon@vger.kernel.org Allocating the sysfs attribute name only if needed and only with the required minimum length looks optimal, but does not take the additional overhead for both devm_ data structures and the allocation header itself into account. This also results in unnecessary memory fragmentation. Move the sysfs name string into struct hwmon_device_attribute and give it a sufficient length to reduce this overhead. Signed-off-by: Guenter Roeck --- drivers/hwmon/hwmon.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/drivers/hwmon/hwmon.c b/drivers/hwmon/hwmon.c index 58c328f4508d..3932f9276c07 100644 --- a/drivers/hwmon/hwmon.c +++ b/drivers/hwmon/hwmon.c @@ -38,12 +38,15 @@ struct hwmon_device { #define to_hwmon_device(d) container_of(d, struct hwmon_device, dev) +#define MAX_SYSFS_ATTR_NAME_LENGTH 32 + struct hwmon_device_attribute { struct device_attribute dev_attr; const struct hwmon_ops *ops; enum hwmon_sensor_types type; u32 attr; int index; + char name[MAX_SYSFS_ATTR_NAME_LENGTH]; }; #define to_hwmon_attr(d) \ @@ -261,20 +264,18 @@ static struct attribute *hwmon_genattr(struct device *dev, if ((mode & S_IWUGO) && !ops->write) return ERR_PTR(-EINVAL); + hattr = devm_kzalloc(dev, sizeof(*hattr), GFP_KERNEL); + if (!hattr) + return ERR_PTR(-ENOMEM); + if (type == hwmon_chip) { name = (char *)template; } else { - name = devm_kzalloc(dev, strlen(template) + 16, GFP_KERNEL); - if (!name) - return ERR_PTR(-ENOMEM); - scnprintf(name, strlen(template) + 16, template, + scnprintf(hattr->name, sizeof(hattr->name), template, index + hwmon_attr_base(type)); + name = hattr->name; } - hattr = devm_kzalloc(dev, sizeof(*hattr), GFP_KERNEL); - if (!hattr) - return ERR_PTR(-ENOMEM); - hattr->type = type; hattr->attr = attr; hattr->index = index; -- 2.5.0