Re: [PATCH 9/9] mptfc: convert mptfc to use fc queueing helper.

[Mike Christie <michaelc@cs.wisc.edu>]

Michael Reed wrote:
> 
> michaelc@cs.wisc.edu wrote:
>> From: Mike Christie <michaelc@cs.wisc.edu>
>>
>> Convert mptfc to use fc queueing helper.
> 
> I've been trying to exercise the fusion FC change.
> I can't seem to force the code into returning either
> TARGET_BUSY or DID_NO_CONNECT.  Any suggestions on

Did you mean DID_IMM_RETRY in the original code?

> how I might get a command down to the driver while
> the rport is blocked or in DEVLOSS_PENDING?
> 
> I've been running 32 outstanding commands to 16 targets,
> disabling/enabling the various FC switch ports, AND
> I disabled the usage of the scsi_host_lock in
> fc_remote_port_delete() and I unlock/relock it in the
> mptfc_qmnd() function.
> 

For FC it is a small window where the rport is being blocked but the 
scsi_device is not yet in the blocked state. Instead of lots of targets 
you want lots of devices on just one target.

To test it with just one device you can just add a sleep in 
fc_remote_port_delete after the port_state and flags are set and the 
host lock is dropped and before the call to scsi_target_block.

        rport->port_state = FC_PORTSTATE_BLOCKED;

         rport->flags |= FC_RPORT_DEVLOSS_PENDING;

         spin_unlock_irqrestore(shost->host_lock, flags);

         if (rport->roles & FC_PORT_ROLE_FCP_INITIATOR &&
             shost->active_mode & MODE_TARGET)
                 fc_tgt_it_nexus_destroy(shost, (unsigned long)rport);


ssleep(1);

         scsi_target_block(&rport->dev);