PERFORCE change 138048 for review

[Hans Petter Selasky]

http://perforce.freebsd.org/chv.cgi?CH=138048

Change 138048 by hselasky at hselasky_laptop001 on 2008/03/18 20:46:22

	
	Add comment about thread safety.

Affected files ...

.. //depot/projects/usb/src/sys/dev/usb/usb_transfer.c#122 edit

Differences ...

==== //depot/projects/usb/src/sys/dev/usb/usb_transfer.c#122 (text+ko) ====

@@ -3872,6 +3872,10 @@
  * than 30 seconds is treated like a 30 second timeout. This USB stack
  * does not allow control requests without a timeout.
  *
+ * NOTE: This function is thread safe. All calls to
+ * "usbd_do_request_flags" will be serialised by the use of an
+ * internal "sx_lock".
+ *
  * Returns:
  *    0: Success
  * Else: Failure