Re: [PATCH] scsi: Add SHT->unlocked_qcmd for host_lock less SHT->queuecommand() dispatch

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

On 10/26/2010 07:32 PM, Nicholas A. Bellinger wrote:
> diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c
> index fec47de..f5933dd 100644
> --- a/drivers/scsi/iscsi_tcp.c
> +++ b/drivers/scsi/iscsi_tcp.c
> @@ -882,6 +882,7 @@ static struct scsi_host_template iscsi_sw_tcp_sht = {
>   	.target_alloc		= iscsi_target_alloc,
>   	.proc_name		= "iscsi_tcp",
>   	.this_id		= -1,
> +	.unlocked_qcmd		= 1,
>   };
>
>   static struct iscsi_transport iscsi_sw_tcp_transport = {
> diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
> index 633e090..7e4134e 100644
> --- a/drivers/scsi/libiscsi.c
> +++ b/drivers/scsi/libiscsi.c
> @@ -1615,7 +1615,6 @@ int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
>
>   	host = sc->device->host;
>   	ihost = shost_priv(host);
> -	spin_unlock(host->host_lock);
>
>   	cls_session = starget_to_session(scsi_target(sc->device));
>   	session = cls_session->dd_data;
> @@ -1706,7 +1705,6 @@ int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
>
>   	session->queued_cmdsn++;
>   	spin_unlock(&session->lock);
> -	spin_lock(host->host_lock);
>   	return 0;
>
>   prepd_reject:
> @@ -1716,7 +1714,6 @@ reject:
>   	spin_unlock(&session->lock);
>   	ISCSI_DBG_SESSION(session, "cmd 0x%x rejected (%d)\n",
>   			  sc->cmnd[0], reason);
> -	spin_lock(host->host_lock);
>   	return SCSI_MLQUEUE_TARGET_BUSY;
>
>   prepd_fault:
> @@ -1733,7 +1730,6 @@ fault:
>   		scsi_in(sc)->resid = scsi_in(sc)->length;
>   	}
>   	done(sc);
> -	spin_lock(host->host_lock);
>   	return 0;
>   }
>   EXPORT_SYMBOL_GPL(iscsi_queuecommand);


Hey,

iscsi_tcp, drivers/infiniband/ulp/iser/ib_iser, drivers/scsi/cxgb3i, 
drivers/scsi/bnx2i, and drivers/scsi/be2iscsi use libiscsi's 
iscsi_queuecommand function, so they should all use the same setting 
unlocked_qcmd=1.