PERFORCE change 102585 for review

[Hans Petter Selasky]

http://perforce.freebsd.org/chv.cgi?CH=102585

Change 102585 by hselasky at hselasky_mini_itx on 2006/07/27 19:33:41

	Optimize UHCI and EHCI drivers by not scanning TD chains from the 
	beginning, but rather store the position of the last checked TD 
	and continue on from there.

Affected files ...

.. //depot/projects/usb/src/sys/dev/usb/ehci.c#7 edit
.. //depot/projects/usb/src/sys/dev/usb/ohci.c#7 edit
.. //depot/projects/usb/src/sys/dev/usb/uhci.c#7 edit
.. //depot/projects/usb/src/sys/dev/usb/usb_subr.h#14 edit

Differences ...

==== //depot/projects/usb/src/sys/dev/usb/ehci.c#7 (text+ko) ====

@@ -1119,7 +1119,7 @@
 
 			DPRINTFN(12, ("xfer=%p active\n", xfer));
 
-			for(td = xfer->td_transfer_first;
+			for(td = xfer->td_transfer_cache;
 			    td != NULL;
 			    td = ((td == xfer->td_transfer_last) ? NULL : td->obj_next))
 			{
@@ -1134,6 +1134,8 @@
 				{
 					DPRINTFN(12, ("xfer=%p is still "
 						      "active\n", xfer));
+					/* update cache */
+					xfer->td_transfer_cache = td;
 					goto done;
 				}
 
@@ -1429,7 +1431,8 @@
 		     xfer->address, UE_GET_ADDR(xfer->endpoint),
 		     xfer->length, xfer->udev->speed));
 
-	td = (xfer->td_transfer_first = xfer->td_start);
+	td = (xfer->td_transfer_first = 
+	      xfer->td_transfer_cache = xfer->td_start);
 
 	buf_offset = 0;
 	usbd_get_page(&(xfer->buf_data), buf_offset, &buf_res);

==== //depot/projects/usb/src/sys/dev/usb/ohci.c#7 (text+ko) ====


==== //depot/projects/usb/src/sys/dev/usb/uhci.c#7 (text+ko) ====

@@ -969,7 +969,7 @@
 
 			DPRINTFN(12, ("xfer=%p active\n", xfer));
 
-			for(td = xfer->td_transfer_first;
+			for(td = xfer->td_transfer_cache;
 			    td != NULL;
 			    td = ((td == xfer->td_transfer_last) ? NULL : td->obj_next))
 			{
@@ -984,6 +984,9 @@
 				{
 					DPRINTFN(12, ("xfer=%p is still "
 						      "active\n", xfer));
+
+					/* update cache */
+					xfer->td_transfer_cache = td;
 					goto done;
 				}
 
@@ -1229,7 +1232,8 @@
 		     xfer->address, UE_GET_ADDR(xfer->endpoint),
 		     xfer->length, xfer->udev->speed));
 
-	td = (xfer->td_transfer_first = xfer->td_start);
+	td = (xfer->td_transfer_first = 
+	      xfer->td_transfer_cache = xfer->td_start);
 
 	buf_offset = 0;
 	usbd_get_page(&(xfer->buf_data), buf_offset, &buf_res);

==== //depot/projects/usb/src/sys/dev/usb/usb_subr.h#14 (text+ko) ====

@@ -405,6 +405,7 @@
 	void *td_start;
 	void *td_transfer_first;
 	void *td_transfer_last;
+        void *td_transfer_cache;
 
 #ifdef USB_COMPAT_OLD
 	struct usbd_xfer *	alloc_xfer; /* the real transfer */