iio: Avoid unnecessary kasprintf

name_format already contains the final name and no format characters. So the
code basically reads:

	dev_attr->attr.name = kstrdup(GFP_KERNEL, name_format);
	if (dev_attr->attr.name == NULL)
		...
	kfree(name_format);

Which means we can save one alloc and free pair per attribute name if we
directly assign name_format to dev_attr->attr.name.

The patch also renames name_format to name to denote that this is indeed the
final name and has no format characters in it.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
index 39fb8cc46373c38caae2711baf24a44e0fd704de..ede16aec20fbd68ec01f729aaffa4543e02a8f0c 100644 (file)
--- a/drivers/iio/industrialio-core.c
+++ b/drivers/iio/industrialio-core.c
@@ -540,7 +540,7 @@ int __iio_device_attr_init(struct device_attribute *dev_attr,
                           enum iio_shared_by shared_by)
 {
        int ret = 0;
-       char *name_format = NULL;
+       char *name = NULL;
        char *full_postfix;
        sysfs_attr_init(&dev_attr->attr);
 
@@ -572,16 +572,15 @@ int __iio_device_attr_init(struct device_attribute *dev_attr,
        if (chan->differential) { /* Differential can not have modifier */
                switch (shared_by) {
                case IIO_SHARED_BY_ALL:
-                       name_format = kasprintf(GFP_KERNEL, "%s", full_postfix);
+                       name = kasprintf(GFP_KERNEL, "%s", full_postfix);
                        break;
                case IIO_SHARED_BY_DIR:
-                       name_format = kasprintf(GFP_KERNEL, "%s_%s",
+                       name = kasprintf(GFP_KERNEL, "%s_%s",
                                                iio_direction[chan->output],
                                                full_postfix);
                        break;
                case IIO_SHARED_BY_TYPE:
-                       name_format
-                               = kasprintf(GFP_KERNEL, "%s_%s-%s_%s",
+                       name = kasprintf(GFP_KERNEL, "%s_%s-%s_%s",
                                            iio_direction[chan->output],
                                            iio_chan_type_name_spec[chan->type],
                                            iio_chan_type_name_spec[chan->type],
@@ -593,8 +592,7 @@ int __iio_device_attr_init(struct device_attribute *dev_attr,
                                ret = -EINVAL;
                                goto error_free_full_postfix;
                        }
-                       name_format
-                               = kasprintf(GFP_KERNEL,
+                       name = kasprintf(GFP_KERNEL,
                                            "%s_%s%d-%s%d_%s",
                                            iio_direction[chan->output],
                                            iio_chan_type_name_spec[chan->type],
@@ -607,16 +605,15 @@ int __iio_device_attr_init(struct device_attribute *dev_attr,
        } else { /* Single ended */
                switch (shared_by) {
                case IIO_SHARED_BY_ALL:
-                       name_format = kasprintf(GFP_KERNEL, "%s", full_postfix);
+                       name = kasprintf(GFP_KERNEL, "%s", full_postfix);
                        break;
                case IIO_SHARED_BY_DIR:
-                       name_format = kasprintf(GFP_KERNEL, "%s_%s",
+                       name = kasprintf(GFP_KERNEL, "%s_%s",
                                                iio_direction[chan->output],
                                                full_postfix);
                        break;
                case IIO_SHARED_BY_TYPE:
-                       name_format
-                               = kasprintf(GFP_KERNEL, "%s_%s_%s",
+                       name = kasprintf(GFP_KERNEL, "%s_%s_%s",
                                            iio_direction[chan->output],
                                            iio_chan_type_name_spec[chan->type],
                                            full_postfix);
@@ -624,33 +621,24 @@ int __iio_device_attr_init(struct device_attribute *dev_attr,
 
                case IIO_SEPARATE:
                        if (chan->indexed)
-                               name_format
-                                       = kasprintf(GFP_KERNEL, "%s_%s%d_%s",
+                               name = kasprintf(GFP_KERNEL, "%s_%s%d_%s",
                                                    iio_direction[chan->output],
                                                    iio_chan_type_name_spec[chan->type],
                                                    chan->channel,
                                                    full_postfix);
                        else
-                               name_format
-                                       = kasprintf(GFP_KERNEL, "%s_%s_%s",
+                               name = kasprintf(GFP_KERNEL, "%s_%s_%s",
                                                    iio_direction[chan->output],
                                                    iio_chan_type_name_spec[chan->type],
                                                    full_postfix);
                        break;
                }
        }
-       if (name_format == NULL) {
+       if (name == NULL) {
                ret = -ENOMEM;
                goto error_free_full_postfix;
        }
-       dev_attr->attr.name = kasprintf(GFP_KERNEL,
-                                       name_format,
-                                       chan->channel,
-                                       chan->channel2);
-       if (dev_attr->attr.name == NULL) {
-               ret = -ENOMEM;
-               goto error_free_name_format;
-       }
+       dev_attr->attr.name = name;
 
        if (readfunc) {
                dev_attr->attr.mode |= S_IRUGO;
@@ -661,8 +649,7 @@ int __iio_device_attr_init(struct device_attribute *dev_attr,
                dev_attr->attr.mode |= S_IWUSR;
                dev_attr->store = writefunc;
        }
-error_free_name_format:
-       kfree(name_format);
+
 error_free_full_postfix:
        kfree(full_postfix);