svn commit: r215206 - user/weongyo/usb/sys/dev/usb

[Weongyo Jeong]

Author: weongyo
Date: Fri Nov 12 21:47:36 2010
New Revision: 215206
URL: http://svn.freebsd.org/changeset/base/215206

Log:
  Adds a XXX comment to avoid useless operations that for example, no need
  to copy whole data into a buffer if there's no consumers.

Modified:
  user/weongyo/usb/sys/dev/usb/usb_pf.c

Modified: user/weongyo/usb/sys/dev/usb/usb_pf.c
==============================================================================
--- user/weongyo/usb/sys/dev/usb/usb_pf.c	Fri Nov 12 21:46:58 2010	(r215205)
+++ user/weongyo/usb/sys/dev/usb/usb_pf.c	Fri Nov 12 21:47:36 2010	(r215206)
@@ -1677,6 +1677,11 @@ usbpf_xfertap(struct usb_xfer *xfer, int
 	char *buf, *ptr, *end;
 
 	/*
+	 * XXX check first whether there are any descriptors waiting.  If no
+	 * we don't need to handle this xfer.
+	 */
+
+	/*
 	 * XXX TODO
 	 * Allocating the buffer here causes copy operations twice what's
 	 * really inefficient. Copying usbpf_pkthdr and data is for USB packet