Re: [PATCH] accel: make accel_class a static const structure

From: Tomer Tayar
Date: Mon Jul 03 2023 - 08:09:24 EST


On 20/06/2023 21:25, Greg Kroah-Hartman wrote:
> From: Ivan Orlov <ivan.orlov0322@xxxxxxxxx>
>
> Now that the driver core allows for struct class to be in read-only
> memory, move the accel_class structure to be declared at build time
> placing it into read-only memory, instead of having to be dynamically
> allocated at boot time.
>
> Cc: Oded Gabbay <ogabbay@xxxxxxxxxx>
> Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
> Suggested-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Ivan Orlov <ivan.orlov0322@xxxxxxxxx>
> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

Reviewed-by: Tomer Tayar <ttayar@xxxxxxxxx>

Thanks,
Tomer

> ---
> drivers/accel/drm_accel.c | 21 ++++++++-------------
> 1 file changed, 8 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/accel/drm_accel.c b/drivers/accel/drm_accel.c
> index 4a9baf02439e..2dc187e1ee41 100644
> --- a/drivers/accel/drm_accel.c
> +++ b/drivers/accel/drm_accel.c
> @@ -21,7 +21,6 @@ static DEFINE_SPINLOCK(accel_minor_lock);
> static struct idr accel_minors_idr;
>
> static struct dentry *accel_debugfs_root;
> -static struct class *accel_class;
>
> static struct device_type accel_sysfs_device_minor = {
> .name = "accel_minor"
> @@ -32,23 +31,19 @@ static char *accel_devnode(const struct device *dev, umode_t *mode)
> return kasprintf(GFP_KERNEL, "accel/%s", dev_name(dev));
> }
>
> +static const struct class accel_class = {
> + .name = "accel",
> + .devnode = accel_devnode,
> +};
> +
> static int accel_sysfs_init(void)
> {
> - accel_class = class_create("accel");
> - if (IS_ERR(accel_class))
> - return PTR_ERR(accel_class);
> -
> - accel_class->devnode = accel_devnode;
> -
> - return 0;
> + return class_register(&accel_class);
> }
>
> static void accel_sysfs_destroy(void)
> {
> - if (IS_ERR_OR_NULL(accel_class))
> - return;
> - class_destroy(accel_class);
> - accel_class = NULL;
> + class_unregister(&accel_class);
> }
>
> static int accel_name_info(struct seq_file *m, void *data)
> @@ -116,7 +111,7 @@ void accel_debugfs_init(struct drm_minor *minor, int minor_id)
> void accel_set_device_instance_params(struct device *kdev, int index)
> {
> kdev->devt = MKDEV(ACCEL_MAJOR, index);
> - kdev->class = accel_class;
> + kdev->class = &accel_class;
> kdev->type = &accel_sysfs_device_minor;
> }
>