From: Eric Anholt <eric@anholt.net>
Date: Wed, 4 Jul 2012 17:52:36 +0000 (-0700)
Subject: intel: Add a comment explaining why we early return on matching BO names.
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=fadc9eaf97c0916d5680c1d3b47e80532ede22c1;p=mesa.git

intel: Add a comment explaining why we early return on matching BO names.

Reviewed-by: Chad Versace <chad.versace@linux.intel.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
---

diff --git a/src/mesa/drivers/dri/intel/intel_context.c b/src/mesa/drivers/dri/intel/intel_context.c
index 2494ac79457..378859c2a31 100644
--- a/src/mesa/drivers/dri/intel/intel_context.c
+++ b/src/mesa/drivers/dri/intel/intel_context.c
@@ -893,6 +893,10 @@ intel_process_dri2_buffer(struct intel_context *intel,
    if (!rb)
       return;
 
+   /* We try to avoid closing and reopening the same BO name, because the first
+    * use of a mapping of the buffer involves a bunch of page faulting which is
+    * moderately expensive.
+    */
    if (rb->mt &&
        rb->mt->region &&
        rb->mt->region->name == buffer->name)