[Intel-gfx] [PATCH] drm/i915: Use the engine name directly in the error_state file

[Chris Wilson]

Quoting Michal Wajdeczko (2018-01-09 20:39:09)
> On Tue, 09 Jan 2018 20:33:55 +0100, Michel Thierry  
> <michel.thierry at intel.com> wrote:
> 
> > Instead of using local string names that we will have to keep
> > maintaining, use the engine->name directly.
> >
> > Suggested-by: Michal Wajdeczko <michal.wajdeczko at intel.com>
> > Signed-off-by: Michel Thierry <michel.thierry at intel.com>
> > Cc: Michal Wajdeczko <michal.wajdeczko at intel.com>

I'd a patch to do this, I just had to make sure the tooling was ready
for a name change. At the time, changing this string broke a few igt and
intel_error_decode.

> > ---
> >  drivers/gpu/drm/i915/i915_gpu_error.c | 23 ++++++++++-------------
> >  1 file changed, 10 insertions(+), 13 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c  
> > b/drivers/gpu/drm/i915/i915_gpu_error.c
> > index 94499c24f279..db95ecacdace 100644
> > --- a/drivers/gpu/drm/i915/i915_gpu_error.c
> > +++ b/drivers/gpu/drm/i915/i915_gpu_error.c
> > @@ -34,16 +34,12 @@
> > #include "i915_drv.h"
> > -static const char *engine_str(int engine)
> > -{
> > -     switch (engine) {
> > -     case RCS: return "render";
> > -     case VCS: return "bsd";
> > -     case BCS: return "blt";
> > -     case VECS: return "vebox";
> > -     case VCS2: return "bsd2";
> > -     default: return "";
> > -     }
> > +static const char *engine_str(struct drm_i915_private *i915, int  
> > engine_id)
> > +{
> > +     if (!i915->engine[engine_id])
> > +             return "";
> 
> While unlikely, empty string may be misleading, so maybe better we return
> "<invalid>" or at least "?" here. Also maybe we can do as part of more
> global helper function like
> 
> static inline const char* intel_engine_name(struct intel_engine_cs *engine)
> {
>         return engine ? engine->name : "<invalid>";
> }
> 
> static inline struct intel_engine_cs *
> intel_engine_lookup(struct drm_i915_private *i915, int engine_id)
> {
>         if (engine_id < 0 || engine_id > I915_MAX_ENGINES)
>                 return NULL;
>         return i915->engine[engine_id];
> }
> 
> and then
> 
> static const char *engine_str(struct drm_i915_private *i915, int engine_id)
> {
>         return intel_engine_name(intel_engine_lookup(i915, engine_id));
> }

No need, this is all internal, perma-allocated structs.
-Chris