On Fri, Jun 10, 2011 at 02:55:35PM +0200, Hannes Reinecke wrote: > >Device operation: request queues > >-------------------------------- > > > >The driver queues requests to an arbitrary request queue, and they are > >used by the device on that same queue. > > > What about request ordering? > If requests are placed on arbitrary queues you'll inevitably run on > locking issues to ensure strict request ordering. > I would add here: > > If a device uses more than one queue it is the responsibility of the > device to ensure strict request ordering. Maybe I misunderstand - how can this be the responsibility of the device if the device does not get the information about the original ordering of the requests? For example, if the driver is crazy enough to put all write requests on one queue and all barriers on another one, how is the device supposed to ensure ordering? -- MST -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
