Re: [PATCH] Use ida_simple for SCSI iSCSI transport session id

From: Lee Duncan
Date: Mon Mar 07 2016 - 20:06:24 EST


On 02/12/2016 09:54 AM, James Bottomley wrote:
> On Fri, 2016-02-12 at 09:38 -0800, Lee Duncan wrote:
>> The scsi_transport_iscsi module already uses the ida_simple
>> routines for managing the target ID, if requested to do
>> so. This change replaces an ever-increasing atomic integer
>> that tracks the session ID itself with the ida_simple
>> family of routines. This means that the session ID
>> will be reclaimed and can be reused when the session
>> is freed.
>
> Is reusing session ID's really a good idea? For sequential sessions it
> means that the ID of the next session will be re-used, i.e. the same as
> the previous sessions, which could lead to target confusion. I think
> local uniqueness of session IDs is more important than wrap around
> because sessions are short lived entities and the chances of the same
> session being alive by the time we've wrapped is pretty tiny.
>
> If you can demostrate a multi-target problem, perhaps we should rather
> fix this by making the next session id a target local quantity?
>
> James
>

It looks like Mike and Chris are good with it. And I'd really like to
get rid of yet another atomic int.

Are you satisfied with this one?
--
Lee