On Fri, Mar 30, 2007 at 10:45:26AM +0200, Oliver Neukum wrote: > Am Freitag, 30. M?rz 2007 10:39 schrieb Greg KH: > > > To solve this with locking would require both CPU A and CPU B to take > > > the lock, which means that the urb would have to be submitted with > > > GFP_ATOMIC. > > > > Can't this all be solved with a simple: > > > > ????????get port spinlock > > ????????a = urb->status > > ????????write_busy = 0 > > ????????unlock spinlock > > > > In the callback, and in the write path: > > > > ????????get port spinlock > > ????????if write_busy > > ????????????????unlock > > ????????????????exit > > ????????write_busy = 1 > > ????????unlock port spinlock > > ????????submit_urb > > > > Oops. You are right. That would work. > If you think that's simpler, yes it can be done.
Yes, I think that would be both easier to understand, and easier to prove correct :) thanks, greg k-h ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
