On Wed, 12 Jul 2023, Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx> wrote:
> Hello Jani,
>
> On Wed, Jul 12, 2023 at 05:34:28PM +0300, Jani Nikula wrote:
>> On Wed, 12 Jul 2023, Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx> wrote:
>> > Hello,
>> >
>> > while I debugged an issue in the imx-lcdc driver I was constantly
>> > irritated about struct drm_device pointer variables being named "dev"
>> > because with that name I usually expect a struct device pointer.
>> >
>> > I think there is a big benefit when these are all renamed to "drm_dev".
>> > I have no strong preference here though, so "drmdev" or "drm" are fine
>> > for me, too. Let the bikesheding begin!
>> >
>> > Some statistics:
>> >
>> > $ git grep -ohE 'struct drm_device *\* *[^ (),;]*' v6.5-rc1 | sort | uniq -c | sort -n
>> > 1 struct drm_device *adev_to_drm
>> > 1 struct drm_device *drm_
>> > 1 struct drm_device *drm_dev
>> > 1 struct drm_device *drm_dev
>> > 1 struct drm_device *pdev
>> > 1 struct drm_device *rdev
>> > 1 struct drm_device *vdev
>> > 2 struct drm_device *dcss_drv_dev_to_drm
>> > 2 struct drm_device **ddev
>> > 2 struct drm_device *drm_dev_alloc
>> > 2 struct drm_device *mock
>> > 2 struct drm_device *p_ddev
>> > 5 struct drm_device *device
>> > 9 struct drm_device * dev
>> > 25 struct drm_device *d
>> > 95 struct drm_device *
>> > 216 struct drm_device *ddev
>> > 234 struct drm_device *drm_dev
>> > 611 struct drm_device *drm
>> > 4190 struct drm_device *dev
>> >
>> > This series starts with renaming struct drm_crtc::dev to drm_dev. If
>> > it's not only me and others like the result of this effort it should be
>> > followed up by adapting the other structs and the individual usages in
>> > the different drivers.
>>
>> I think this is an unnecessary change. In drm, a dev is usually a drm
>> device, i.e. struct drm_device *.
>
> Well, unless it's not. Prominently there is
>
> struct drm_device {
> ...
> struct device *dev;
> ...
> };
>
> which yields quite a few code locations using dev->dev which is
> IMHO unnecessary irritating:
>
> $ git grep '\<dev->dev' v6.5-rc1 drivers/gpu/drm | wc -l
> 1633
>
> Also the functions that deal with both a struct device and a struct
> drm_device often use "dev" for the struct device and then "ddev" for
> the drm_device (see for example amdgpu_device_get_pcie_replay_count()).
Why is specifically struct drm_device *dev so irritating to you?
You lead us to believe it's an outlier in kernel, something that goes
against common kernel style, but it's really not:
$ git grep -how "struct [A-Za-z0-9_]\+ \*dev" | sort | uniq -c | sort -rn | head -20
38494 struct device *dev
16388 struct net_device *dev
4184 struct drm_device *dev
2780 struct pci_dev *dev
1916 struct comedi_device *dev
1510 struct mlx5_core_dev *dev
1057 struct mlx4_dev *dev
894 struct b43_wldev *dev
762 struct input_dev *dev
623 struct usbnet *dev
561 struct mlx5_ib_dev *dev
525 struct mt76_dev *dev
465 struct mt76x02_dev *dev
435 struct platform_device *dev
431 struct usb_device *dev
411 struct mt7915_dev *dev
398 struct cx231xx *dev
378 struct mei_device *dev
363 struct ksz_device *dev
359 struct mthca_dev *dev
A good portion of the above also have a dev member.
Are you planning on changing all of the above too, or are you only
annoyed by drm?
I'm really not convinced at all.
BR,
Jani.
--
Jani Nikula, Intel Open Source Graphics Center