Re: [PATCH] drm/amdgpu: do not initialise global variables to 0 or NULL

[Christian König]

Am 03.11.20 um 08:53 schrieb Greg KH:
> On Mon, Nov 02, 2020 at 09:48:25PM +0100, Christian König wrote:
> > Am 03.11.20 um 07:53 schrieb Greg KH:
> > > On Mon, Nov 02, 2020 at 09:06:21PM +0100, Christian König wrote:
> > > > Am 02.11.20 um 20:43 schrieb Alex Deucher:
> > > > > On Mon, Nov 2, 2020 at 1:42 PM Deepak R Varma <mh12gx2825@xxxxxxxxx> wrote:
> > > > > > Initializing global variable to 0 or NULL is not necessary and should
> > > > > > be avoided. Issue reported by checkpatch script as:
> > > > > > ERROR: do not initialise globals to 0 (or NULL).
> > > > > I agree that this is technically correct, but a lot of people don't
> > > > > seem to know that so we get a lot of comments about this code for the
> > > > > variables that are not explicitly set.  Seems less confusing to
> > > > > initialize them even if it not necessary.  I don't have a particularly
> > > > > strong opinion on it however.
> > > > Agree with Alex.
> > > >
> > > > Especially for the module parameters we should have a explicit init value
> > > > for documentation purposes, even when it is 0.
> > > Why is this one tiny driver somehow special compared to the entire rest
> > > of the kernel?  (hint, it isn't...)
> > And it certainly shouldn't :)
> >
> > > Please follow the normal coding style rules, there's no reason to ignore
> > > them unless you like to constantly reject patches like this that get
> > > sent to you.
> > Yeah, that's a rather good point.
> >
> > Not a particular strong opinion on this either, but when something global is
> > set to 0 people usually do this to emphases that it is important that it is
> > zero.
> Again, no, that's not what we have been doing in the kernel for the past
> 20+ years.  If you do not set it to anything, we all know it is
> important for it to be set to 0.  Otherwise we would explicitly set it
> to something else.  And if we don't care, then that too doesn't matter
> so we let it be 0 by not initializing it, it doesn't matter.
>
> I think this very change is what started the whole "kernel janitor"
> movement all those years ago, because it was easily proven that this
> simple change saved both time and memory.

Ok, well that is even better because it is a technical argument.

You have convinced me, the patch is Reviewed-by: Christian König 
<christian.koenig@xxxxxxx>.

Regards,
Christian.

> This shouldn't even be an argument we are having anymore...
>
> thanks,
>
> greg k-h