[Intel-gfx] [PATCH] drm/i915/gtt: Avoid calling kcalloc in a loop when allocating temp bitmaps

[Chris Wilson]

On Mon, Aug 31, 2015 at 06:27:40PM +0200, Michał Winiarski wrote:
> On each call to gen8_alloc_va_range_3lvl we're allocating temporary
> bitmaps needed for error handling. Unfortunately, when we increase
> address space size (48b ppgtt) we do additional (512 - 4) calls to
> kcalloc, increasing latency between exec and actual start of execution
> on the GPU. Let's just do a single kcalloc and setup proper offsets in
> an array, we can also drop the size from free_gen8_temp_bitmaps since
> it's no longer needed.
> 
> Cc: Mika Kuoppala <mika.kuoppala at linux.intel.com>
> Cc: Michel Thierry <michel.thierry at intel.com>
> Signed-off-by: Michał Winiarski <michal.winiarski at intel.com>

Whilst you are here, mind using GFP_TEMPORARY as well?
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre