Jens Axboe wrote: > On Tue, Dec 19 2006, Arjan van de Ven wrote: >> On Tue, 2006-12-19 at 10:35 +0200, Dan Aloni wrote: >>> Hello, >>> >>> scsi_execute_async() has replaced scsi_do_req() a few versions ago, >>> but it also incurred a change of behavior. I noticed that over-queuing >>> a SCSI device using that function causes I/Os to be starved from >>> low-level queuing for no justified reason. >>> >>> I think it makes much more sense to perserve the original behaviour >>> of scsi_do_req() and add the request to the tail of the queue. >> Hi, >> >> some things should really be added to the head of the queue, like >> maintenance requests and error handling requests. Are you sure this is >> the right change? At least I'd expect 2 apis, one for a head and one for >> a "normal" queueing... > > It does sounds broken - head insertion should only be used for careful > internal commands, not be the default way user issued commands. Looking > at the current users, the patch makes sense to me. >
It's worth noting that the hdaps disk protection patches rely on the current behaviour to add 'IDLE IMMEDIATE WITH UNLOAD' commands to the head of the queue.. Another function, or a new parameter for queue position would be needed to retain this functionality - any preference for either?
Regards, Jon. - To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
