[PATCH 2/2] Set DamageSetReportAfterOp to true for the damage extension

Kristian Høgsberg krh at bitplanet.net
Thu Jul 29 17:44:06 PDT 2010

Change the damage extension reporter to queue up events after we chain
to the wrapped functions.  Damage events are typically sent out after
the rendering happens anyway, since we submit batch buffers from the
flush callback chain and then flush client io buffers.  Compositing
managers relie on this order, and there is no way we could reliably
provide damage events to clients before the rendering happens anyway.

By queueing up the damage events before the rendering happens, there's
a risk that the client io buffer may overflow and send the damage
events to the client before the driver has even seen the rendering
request.  Reporting damage events after the rendering fixes this
corner case and better corresponds with how we expect this to work.

Signed-off-by: Kristian Høgsberg <krh at bitplanet.net>
 damageext/damageext.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/damageext/damageext.c b/damageext/damageext.c
index f5265dd..b4bb478 100644
--- a/damageext/damageext.c
+++ b/damageext/damageext.c
@@ -217,6 +217,7 @@ ProcDamageCreate (ClientPtr client)
     if (!AddResource (stuff->damage, DamageExtType, (pointer) pDamageExt))
 	return BadAlloc;
+    DamageSetReportAfterOp (pDamageExt->pDamage, TRUE);
     DamageRegister (pDamageExt->pDrawable, pDamageExt->pDamage);
     if (pDrawable->type == DRAWABLE_WINDOW)

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