Luben Tuikov <luben_tuikov@xxxxxxxxxxx> wrote: > On 08/19/05 15:38, Patrick Mansfield wrote: > The eh_timed_out + eh_strategy_handler is actually pretty perfect, > and _complete_, for any application and purpose in recovering a > LU/device/host (in that order ;-) ). > > > The two problems I see with the hook are: > > > > It calls the driver in interrupt context, so the called function can't > > sleep. > > Consider this: When SCSI Core told you that the command timed out, > A) it has already finished, > B) it hasn't already finished. > > In case A, you can return EH_HANDLED. In case B, you return > EH_NOT_HANDLED, and deal with it in the eh_strategy_handler. > (Hint: you can still "finish" it from there.) > But dealing with it in the eh_strategy_handler means that you may be stopping all IO on the host instance as the first lun returns EH_NOT_HANDLED for LUN based canceling. I still think we can do better here for an LLDD that cannot execute a cancel in interrupt context. Having a error handler that works is a plus, I would hope that some factoring would happen over time from the eh_strategy_handler to some transport (or other factor point) error handler. I would think from a testing, support, and block level multipath predictability sharing code would be a good goal. -andmike -- Michael Anderson andmike@xxxxxxxxxx - : send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
