From: Eric Anholt <eric@anholt.net>
Date: Thu, 27 Feb 2014 18:05:39 +0000 (-0800)
Subject: i965: Always use CPU mappings for BOs on LLC platforms.
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=1990da2568a0da79c6011bd83e7f7fb8bb099827;p=mesa.git

i965: Always use CPU mappings for BOs on LLC platforms.

It looks like there's no big difference for write-only workloads, but
using a CPU map means that if they happen to read without having set the
MAP_READ_BIT, they get 100x the performance for those reads.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
---

diff --git a/src/mesa/drivers/dri/i965/intel_buffer_objects.c b/src/mesa/drivers/dri/i965/intel_buffer_objects.c
index e496836905a..260308a80a2 100644
--- a/src/mesa/drivers/dri/i965/intel_buffer_objects.c
+++ b/src/mesa/drivers/dri/i965/intel_buffer_objects.c
@@ -429,7 +429,7 @@ intel_bufferobj_map_range(struct gl_context * ctx,
 
    if (access & GL_MAP_UNSYNCHRONIZED_BIT)
       drm_intel_gem_bo_map_unsynchronized(intel_obj->buffer);
-   else if (!(access & GL_MAP_READ_BIT)) {
+   else if (!brw->has_llc && !(access & GL_MAP_READ_BIT)) {
       drm_intel_gem_bo_map_gtt(intel_obj->buffer);
       intel_bufferobj_mark_inactive(intel_obj);
    } else {