[Intel-gfx] [PATCH 55/59] drm/i915: Remove fallback poll for ring buffer space

[John Harrison]

On 19/03/2015 15:16, Jani Nikula wrote:
> On Thu, 19 Mar 2015, "Daniel, Thomas" <thomas.daniel at intel.com> wrote:
>>> -	if (&request->list == &ring->request_list)
>>> +	/* It should always be possible to find a suitable request! */
>>> +	if (&request->list == &ring->request_list) {
>>> +		WARN_ON(true);
>>>   		return -ENOSPC;
>>> +	}
>> Don’t we normally say
>> 	if (WARN_ON(&request->list == &ring->request_list))
>> 		return -ENOSPC;
> Yes, particularly since we've amended WARN_ON within i915 to print out
> the condition that failed. "true" is not very useful with that. ;)
>
> BR,
> Jani.
>
The issue I have with 'if(WARN_ON(x))' is that it looks like something 
that would disappear in a non debugging build. Whereas, this is a check 
that wants to exist regardless of build options.