[Intel-gfx] [PATCH 03/22] drm/i915: Shrink per-platform watermark configuration

[Tvrtko Ursulin]

On 05/10/2016 18:11, Ville Syrjälä wrote:
> On Wed, Oct 05, 2016 at 01:33:30PM +0100, Tvrtko Ursulin wrote:
>> From: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
>>
>> Use types of more appropriate size in struct
>> intel_watermark_params to save 512 bytes of .rodata.
>>
>> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
>> ---
>>   drivers/gpu/drm/i915/intel_drv.h | 10 +++++-----
>>   drivers/gpu/drm/i915/intel_pm.c  |  4 ++--
>>   2 files changed, 7 insertions(+), 7 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
>> index c52b1d3a7ba0..59a73f8ca7af 100644
>> --- a/drivers/gpu/drm/i915/intel_drv.h
>> +++ b/drivers/gpu/drm/i915/intel_drv.h
>> @@ -799,11 +799,11 @@ struct intel_plane {
>>   };
>>   
>>   struct intel_watermark_params {
>> -	unsigned long fifo_size;
>> -	unsigned long max_wm;
>> -	unsigned long default_wm;
>> -	unsigned long guard_size;
>> -	unsigned long cacheline_size;
>> +	u16 fifo_size;
>> +	u16 max_wm;
>> +	u8 default_wm;
>> +	u8 guard_size;
>> +	u8 cacheline_size;
>>   };
> This thing has been bugging me since forever. And yet I never sent out a
> fix. We could probably shrink things furher by tossing out a bunch of
> the data since it's not all that diverse. But this looks like a decent
> first step.
>
> The other thing that bugs me about these is the defines for the actual
> values. Makes it just that much harder to figure out what the actual
> values are. I'm pretty sure I have a branch or two where I kill the
> defines but naturally I can't find it right now. I'm too lazy to
> double check the values now with this indirection in place, but your
> choice of types does look reasonable, so
>
> Acked-by: Ville Syrjälä <ville.syrjala at linux.intel.com>

Thanks.

Btw we can shave one more kilobyte by similarly shrinking "struct 
video_levels" and "struct tv_mode". u8/u16 are enough to replace most of 
the ints there.  If you want to ack that in principle I can include a 
patch for that in the next round.

Regards,

Tvrtko