[Mesa-dev] [PATCH 2/2] glx: provide a way to disable DRI3 using an environment variable

[Martin Peres]

This provides an easy way to test differences in rendering performance
or conformance between DRI2 and DRI3.

Signed-off-by: Martin Peres <martin.peres at linux.intel.com>
---
 docs/envvars.html  | 1 +
 src/glx/dri3_glx.c | 5 +++++
 2 files changed, 6 insertions(+)

diff --git a/docs/envvars.html b/docs/envvars.html
index 31d14a4..73d8919 100644
--- a/docs/envvars.html
+++ b/docs/envvars.html
@@ -115,6 +115,7 @@ See the <a href="xlibdriver.html">Xlib software driver page</a> for details.
 <li>MESA_GLX_FORCE_ALPHA - if set, forces RGB windows to have an alpha channel.
 <li>MESA_GLX_DEPTH_BITS - specifies default number of bits for depth buffer.
 <li>MESA_GLX_ALPHA_BITS - specifies default number of bits for alpha channel.
+<li>MESA_GLX_DRI3_DISABLE - disables DRI3 support.
 </ul>
 
 
diff --git a/src/glx/dri3_glx.c b/src/glx/dri3_glx.c
index ff77a91..5246737 100644
--- a/src/glx/dri3_glx.c
+++ b/src/glx/dri3_glx.c
@@ -2092,6 +2092,11 @@ dri3_create_display(Display * dpy)
    xcb_generic_error_t                  *error;
    const xcb_query_extension_reply_t    *extension;
 
+   if (getenv("MESA_GLX_DRI3_DISABLE")) {
+      ErrorMessageF("DRI3 disabled by the environment\n");
+      return NULL;
+   }
+
    xcb_prefetch_extension_data(c, &xcb_dri3_id);
    xcb_prefetch_extension_data(c, &xcb_present_id);
 
-- 
2.3.7