Hello, Alan. On Tue, Jan 15, 2013 at 01:20:58PM -0500, Alan Stern wrote: > It may not be so easy. When the SCSI async thread probes the new disk, > it has to do I/O. So it needs to use a scheduler. > > But maybe it could use a built-in trivial scheduler until the proper > one is loaded. Then the loading could be asynchronous. It can be done. Noop is always built-in and block IO can do IOs with noop. The problem here is that request_module() is done synchronously during evelator_init(). We can punt that to a work item so that the elevator is switched on load completion. There are some nastiness involved tho - if module probing returns before elevator switch happens, the userland can observe elevator being switched after some indetermined short period of time, which can, for example, break scripts adjusting elevator knobs and etc... I *think* it'll be best to allow scoped synchronization of async ops. Looking into it. Thanks. -- tejun -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
