[Intel-gfx] [PATCH 2/4] drm/i915/guc: Print error name on CTB (de)registration failure

[Daniel Vetter]

On Wed, Aug 18, 2021 at 5:11 PM Michal Wajdeczko
<michal.wajdeczko at intel.com> wrote:
>
>
>
> On 18.08.2021 16:20, Daniel Vetter wrote:
> > On Thu, Jul 01, 2021 at 05:55:11PM +0200, Michal Wajdeczko wrote:
> >> Instead of plain error value (%d) print more user friendly error
> >> name (%pe).
> >>
> >> Signed-off-by: Michal Wajdeczko <michal.wajdeczko at intel.com>
> >> ---
> >>  drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c | 8 ++++----
> >>  1 file changed, 4 insertions(+), 4 deletions(-)
> >>
> >> diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c
> >> index a26bb55c0898..18d52c39f0c2 100644
> >> --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c
> >> +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c
> >> @@ -167,8 +167,8 @@ static int ct_register_buffer(struct intel_guc_ct *ct, u32 type,
> >>      err = guc_action_register_ct_buffer(ct_to_guc(ct), type,
> >>                                          desc_addr, buff_addr, size);
> >>      if (unlikely(err))
> >> -            CT_ERROR(ct, "Failed to register %s buffer (err=%d)\n",
> >> -                     guc_ct_buffer_type_to_str(type), err);
> >> +            CT_ERROR(ct, "Failed to register %s buffer (%pe)\n",
> >> +                     guc_ct_buffer_type_to_str(type), ERR_PTR(err));
> >
> > errname() is what you want here, not this convoluted jumping through hoops
> > to fake an error pointer.
>
> nope, I was already trying that shortcut, but errname() is not exported
> so we fail with
>
> ERROR: modpost: "errname" [drivers/gpu/drm/i915/i915.ko] undefined!
>
> so unless we add that export we must follow initial approach [1]

Then we export that function. This is all open source, we can actually
fix things up, there should _never_ be a need to hack around things
like this.

And yes I'm keenly aware that there's a pile of i915-gem code which
outright flaunts this principle, but that doesn't mean we should
continue with that. scripts/get_maintainers.pl can help with finding
all the people you need to cc on that export patch.
-Daniel

>
> -Michal
>
> [1]
> https://cgit.freedesktop.org/drm/drm-tip/commit/?id=57f5677e535ba24b8926a7125be2ef8d7f09323c
>
> >
> > With that: Reviewed-by: Daniel Vetter <daniel.vetter at ffwll.ch>
> >>      return err;
> >>  }
> >>
> >> @@ -195,8 +195,8 @@ static int ct_deregister_buffer(struct intel_guc_ct *ct, u32 type)
> >>      int err = guc_action_deregister_ct_buffer(ct_to_guc(ct), type);
> >>
> >>      if (unlikely(err))
> >> -            CT_ERROR(ct, "Failed to deregister %s buffer (err=%d)\n",
> >> -                     guc_ct_buffer_type_to_str(type), err);
> >> +            CT_ERROR(ct, "Failed to deregister %s buffer (%pe)\n",
> >> +                     guc_ct_buffer_type_to_str(type), ERR_PTR(err));
> >>      return err;
> >>  }
> >>
> >> --
> >> 2.25.1
> >>
> >> _______________________________________________
> >> Intel-gfx mailing list
> >> Intel-gfx at lists.freedesktop.org
> >> https://lists.freedesktop.org/mailman/listinfo/intel-gfx
> >



-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch