dix: Pass ClientPtr to FlushCallback

This change has two effects:

1. Only calls FlushCallbacks when we're actually flushing data to a
   client. The unnecessary FlushCallback calls could cause significant
   performance degradation with compositing, which is significantly
   reduced even without any driver changes.

2. By passing the ClientPtr to FlushCallbacks, drivers can completely
   eliminate unnecessary flushing of GPU commands by keeping track of
   whether we're flushing any XDamageNotify events to the client for
   which the corresponding rendering commands haven't been flushed to
   the GPU yet.

Reviewed-by: Adam Jackson <ajax@redha.com>
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>

2 files changed, 4 insertions, 7 deletions

diff --git a/os/connection.c b/os/connection.c
index 4294ee7eb..a901ebf3c 100644
--- a/os/connection.c
+++ b/os/connection.c
@@ -908,7 +908,7 @@ CloseDownConnection(ClientPtr client)
     OsCommPtr oc = (OsCommPtr) client->osPrivate;
 
     if (FlushCallback)
-        CallCallbacks(&FlushCallback, NULL);
+        CallCallbacks(&FlushCallback, client);
 
     if (oc->output)
 	FlushClient(client, oc, (char *) NULL, 0);
diff --git a/os/io.c b/os/io.c
index 88edf1272..ff0ec3da7 100644
--- a/os/io.c
+++ b/os/io.c
@@ -598,9 +598,6 @@ FlushAllOutput(void)
     register ClientPtr client, tmp;
     Bool newoutput = NewOutputPending;
 
-    if (FlushCallback)
-        CallCallbacks(&FlushCallback, NULL);
-
     if (!newoutput)
         return;
 
@@ -767,9 +764,6 @@ WriteToClient(ClientPtr who, int count, const void *__buf)
             NewOutputPending = FALSE;
         }
 
-        if (FlushCallback)
-            CallCallbacks(&FlushCallback, NULL);
-
         return FlushClient(who, oc, buf, count);
     }
 
@@ -815,6 +809,9 @@ FlushClient(ClientPtr who, OsCommPtr oc, const void *__extraBuf, int extraCount)
     if (!notWritten)
         return 0;
 
+    if (FlushCallback)
+        CallCallbacks(&FlushCallback, who);
+
     todo = notWritten;
     while (notWritten) {
         long before = written;  /* amount of whole thing written */