xen/scsiback: Make TMF processing slightly faster

Target drivers must guarantee that struct se_cmd and struct se_tmr_req
exist as long as target_tmr_work() is in progress. Since the last
access by the LIO core is a call to .check_stop_free() and since the
Xen scsiback .check_stop_free() drops a reference to the TMF, it is
already guaranteed that the struct se_cmd that corresponds to the TMF
exists as long as target_tmr_work() is in progress. Hence change the
second argument of transport_generic_free_cmd() from 1 into 0.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: David Disseldorp <ddiss@suse.de>
Cc: xen-devel@lists.xenproject.org
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

drivers/xen/xen-scsiback.c

@@ -614,7 +614,7 @@ static void scsiback_device_action(struct vscsibk_pend *pending_req,
 		SUCCESS : FAILED;
 
 	scsiback_do_resp_with_sense(NULL, err, 0, pending_req);
-	transport_generic_free_cmd(&pending_req->se_cmd, 1);
+	transport_generic_free_cmd(&pending_req->se_cmd, 0);
 	return;
 
 err: