leandrof/linux
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

drm/i915: Make contexts non-snooped on non-LLC platforms

Browse Source 
We don't do CPU access to GPU contexts so making the GPU access snoop
the CPU caches seems silly, and potentially expensive.

v2: Use !IS_VALLEYVIEW instead of HAS_LLC as this is really
    about what the PTEs can represent.
    Add a comment clarifying the situation.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This commit is contained in:
Ville Syrjälä 2014-04-04 16:36:10 +03:00 committed by Daniel Vetter
parent 4e04632e88
commit ad2ac08bf3
1 changed files with 9 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
drivers/gpu/drm/i915/i915_gem_context.c
View File

@ -240,7 +240,15 @@ __create_hw_context(struct drm_device *dev,
return ERR_PTR(-ENOMEM);
}
if (INTEL_INFO(dev)->gen >= 7) {
/*
* Try to make the context utilize L3 as well as LLC.
*
* On VLV we don't have L3 controls in the PTEs so we
* shouldn't touch the cache level, especially as that
* would make the object snooped which might have a
* negative performance impact.
*/
if (INTEL_INFO(dev)->gen >= 7 && !IS_VALLEYVIEW(dev)) {
ret = i915_gem_object_set_cache_level(ctx->obj,
I915_CACHE_L3_LLC);
/* Failure shouldn't ever happen this early */