[Intel-gfx] [RFC PATCH 124/162] drm/i915/lmem: allocate HWSP in lmem

[Matthew Auld]

On 27/11/2020 13:55, Chris Wilson wrote:
> Quoting Matthew Auld (2020-11-27 12:06:40)
>> From: Michel Thierry <michel.thierry at intel.com>
> 
> Rationale goes here.
> 
> Is this wise? HWSP is very frequently read by the CPU, and expected to
> be cached on the CPU.
> 
> What do the performance profiles indicate?

Do you have a recommendation for an existing selftest or IGT to help 
measure this?

Also are you suggesting moving this to system memory, or just using a 
different mapping type, if it's placed in local memory? Or maybe try 
both? Although I'm pretty sceptical about !wc for local memory.

> -Chris
>