[PATCH 2/4] dix: Tune dtrace hooks around Dispatch

[Adam Jackson]

Don't call LookupMajorName if the hooks aren't active, it's quite expensive.

Before:
40000000 trep @   0.0009 msec (1087458.5/sec): PutImage 10x10 square
60000000 trep @   0.0005 msec (2012238.6/sec): ShmPutImage 10x10 square

After:
40000000 trep @   0.0009 msec (1109091.3/sec): PutImage 10x10 square
60000000 trep @   0.0005 msec (2072652.2/sec): ShmPutImage 10x10 square

Signed-off-by: Adam Jackson <ajax at redhat.com>
---
 dix/dispatch.c |   14 +++++++++-----
 1 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/dix/dispatch.c b/dix/dispatch.c
index b39271f..bb95368 100644
--- a/dix/dispatch.c
+++ b/dix/dispatch.c
@@ -425,9 +425,11 @@ Dispatch(void)
 			client->minorOp = ext->MinorOpcode(client);
 		}
 #ifdef XSERVER_DTRACE
-		XSERVER_REQUEST_START(LookupMajorName(client->majorOp), client->majorOp,
-			      ((xReq *)client->requestBuffer)->length,
-			      client->index, client->requestBuffer);
+		if (XSERVER_REQUEST_START_ENABLED())
+		    XSERVER_REQUEST_START(LookupMajorName(client->majorOp),
+					  client->majorOp,
+					  ((xReq *)client->requestBuffer)->length,
+					  client->index, client->requestBuffer);
 #endif
 		if (result > (maxBigRequestSize << 2))
 		    result = BadLength;
@@ -438,8 +440,10 @@ Dispatch(void)
 		    XaceHookAuditEnd(client, result);
 		}
 #ifdef XSERVER_DTRACE
-		XSERVER_REQUEST_DONE(LookupMajorName(client->majorOp), client->majorOp,
-			      client->sequence, client->index, result);
+		if (XSERVER_REQUEST_DONE_ENABLED())
+		    XSERVER_REQUEST_DONE(LookupMajorName(client->majorOp),
+					 client->majorOp, client->sequence,
+					 client->index, result);
 #endif
 
 		if (client->noClientException != Success)
-- 
1.7.7