Re: [PATCH v7 09/44] [media] media: add a debug message to warn about gobj creation/removal

[Mauro Carvalho Chehab <mchehab@osg.samsung.com>]

Em Tue, 25 Aug 2015 11:51:35 -0600
Shuah Khan <shuahkhan@gmail.com> escreveu:

> On Sun, Aug 23, 2015 at 2:17 PM, Mauro Carvalho Chehab
> <mchehab@osg.samsung.com> wrote:
> > It helps to check if the media controller is doing the
> > right thing with the object creation and removal.
> >
> > No extra code/data will be produced if DEBUG or
> > CONFIG_DYNAMIC_DEBUG is not enabled.
> >
> > Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
> > Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
> > Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
> >
> > diff --git a/drivers/media/media-entity.c b/drivers/media/media-entity.c
> > index 36d725ec5f3d..6d515e149d7f 100644
> > --- a/drivers/media/media-entity.c
> > +++ b/drivers/media/media-entity.c
> > @@ -27,6 +27,69 @@
> >  #include <media/media-device.h>
> >
> >  /**
> > + *  dev_dbg_obj - Prints in debug mode a change on some object
> > + *
> > + * @event_name:        Name of the event to report. Could be __func__
> > + * @gobj:      Pointer to the object
> > + *
> > + * Enabled only if DEBUG or CONFIG_DYNAMIC_DEBUG. Otherwise, it
> > + * won't produce any code.
> > + */
> > +static inline const char *gobj_type(enum media_gobj_type type)
> > +{
> > +       switch (type) {
> > +       case MEDIA_GRAPH_ENTITY:
> > +               return "entity";
> > +       case MEDIA_GRAPH_PAD:
> > +               return "pad";
> > +       case MEDIA_GRAPH_LINK:
> > +               return "link";
> > +       default:
> > +               return "unknown";
> > +       }
> > +}
> > +
> 
> Shouldn't the above gobj_type be defined in if defined(DEBUG) || defined
> (CONFIG_DYNAMIC_DEBUG) scope? Unless gobj_type() is used from
> other places, you will see defined, but not used warning when DEBUG
> and CONFIG_DYNAMIC_DEBUG are undefined.

No need. The function was declared as inline. it won't be at the
text segment if not used.

> Kind of related, maybe we should be looking into adding trace event
> support for media as opposed to dynamic and debug.

I already explained why we need debug here. See the discussions of 
patch 7/8 on the previous series.

Regards,
Mauro