[Intel-gfx] [PATCH v4] drm/i915/gt: allow setting generic data pointer

[Chris Wilson]

Quoting Andi Shyti (2020-03-07 12:55:31)
> Hi Chris,
> 
> On Sat, Mar 07, 2020 at 12:07:22PM +0000, Chris Wilson wrote:
> > Quoting Andi Shyti (2020-03-06 23:03:44)
> > > -void debugfs_gt_register_files(struct intel_gt *gt,
> > > -                              struct dentry *root,
> > > -                              const struct debugfs_gt_file *files,
> > > -                              unsigned long count)
> > > +void intel_gt_debugfs_register_files(struct dentry *root,
> > > +                                    const struct debugfs_gt_file *files,
> > > +                                    unsigned long count, void *data)
> > >  {
> > >         while (count--) {
> > > -               if (!files->eval || files->eval(gt))
> > > +               if (!files->eval || files->eval(data))
> > >                         debugfs_create_file(files->name,
> > > -                                           0444, root, gt,
> > > +                                           0444, root, data,
> > >                                             files->fops);
> > >  
> > 
> > And now we are not a intel_gt routine, you'll want to move again :)
> > i915_debugfs_utils.c ? :)
> 
> Actually, this is what it came to and this was the first
> discussion I had with Daniele and that's also why I was loyal to
> th "_gt_" wrappers until the end. But I had to agree that this
> was becoming more a limitation.
> 
> The biggest difference left, which by the way is the real
> distinguishing factor other than the *gt pointer, is that we
> create files under gt directory, instead of having the root
> imposed by the drm (even though the caller can eventually choose
> different roots).
> 
> We could perhaps store the root pointer in the intel_gt
> structure so that this function stays de facto an intel_gt
> routine and the caller doesn't need to care where the files will
> be generated. This is what we planned to do with sysfs as well.
> 
> What do you think?

I thought we were passing along the root. If not I think we should, more
of a debugfs constructor context?

The main thing of course is not to overengineer and do the minimal
necessary for the immediate users we have. We can always extend and
refactor for a third user, etc, etc.

So if this works for gt + children, go for it and worry about tomorrow,
tomorrow. Trusting our good practice for "a stitch in time saves nine".
-Chris