[PATCH] present: Query the right CRTC to use each time

[Chris Wilson]

As the CRTCs may be reconfigured between each invocation, we can not
assume that the previous CRTC we used last time will still be valid for
this call. Either we need a way to validate the CRTC or, more
conveniently, query the CRTC to use each time. Note, that this still
does not validate the CRTC is passed in by the user - and xshmfence does
not mix well with asynchronous errors from X (i.e. the client can
trivially deadlock waiting for a signal that will never come).

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 present/present.c | 11 ++---------
 1 file changed, 2 insertions(+), 9 deletions(-)

diff --git a/present/present.c b/present/present.c
index e35de94..d1bb9d4 100644
--- a/present/present.c
+++ b/present/present.c
@@ -673,15 +673,8 @@ present_pixmap(WindowPtr window,
 
     if (!screen_priv || !screen_priv->info)
         target_crtc = NULL;
-    else if (!target_crtc) {
-        /* Update the CRTC if we have a pixmap or we don't have a CRTC
-         */
-        if (!pixmap)
-            target_crtc = window_priv->crtc;
-
-        if (!target_crtc)
-            target_crtc = present_get_crtc(window);
-    }
+    else if (!target_crtc)
+        target_crtc = present_get_crtc(window);
 
     present_get_ust_msc(window, target_crtc, &ust, &crtc_msc);
 
-- 
2.0.0.rc4