[PATCH 05/12] fnic: Convert to host_lock less w/ interrupts disabled externally

Nicholas A. Bellinger
2010-12-19T21:22:43Z

From: Nicholas Bellinger <nab@linux-iscsi.org>

This patch converts fnic to run in host_lock less mode with the new
IRQ_DISABLE_SCSI_QCMD() that disables interrupts while calling ->queuecommand()
dispatch. It also drops the legacy host_lock unlock optimization.

Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
---
drivers/scsi/fnic/fnic_scsi.c | 14 +++-----------
1 files changed, 3 insertions(+), 11 deletions(-)

diff --git a/drivers/scsi/fnic/fnic_scsi.c b/drivers/scsi/fnic/fnic_scsi.c
index 22d0240..9f51beb 100644
--- a/drivers/scsi/fnic/fnic_scsi.c
+++ b/drivers/scsi/fnic/fnic_scsi.c
@@ -349,7 +349,8 @@ static inline int fnic_queue_wq_copy_desc(struct fnic *fnic,
* Routine to send a scsi cdb
* Called with host_lock held and interrupts disabled.
*/
-static int fnic_queuecommand_lck(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
+static int fnic_queuecommand_irq_disable(struct scsi_cmnd *sc,
+ void (*done)(struct scsi_cmnd *))
{
struct fc_lport *lp;
struct fc_rport *rport;
@@ -373,13 +374,6 @@ static int fnic_queuecommand_lck(struct scsi_cmnd *sc, void (*done)(struct scsi_
if (lp->state != LPORT_ST_READY || !(lp->link_up))
return SCSI_MLQUEUE_HOST_BUSY;

- /*
- * Release host lock, use driver resource specific locks from here.
- * Don't re-enable interrupts in case they were disabled prior to the
- * caller disabling them.
- */
- spin_unlock(lp->host->host_lock);
-
/* Get a new io_req for this SCSI IO */
fnic = lport_priv(lp);

@@ -452,12 +446,10 @@ static int fnic_queuecommand_lck(struct scsi_cmnd *sc, void (*done)(struct scsi_
}
}
out:
- /* acquire host lock before returning to SCSI */
- spin_lock(lp->host->host_lock);
return ret;
}

-DEF_SCSI_QCMD(fnic_queuecommand)
+IRQ_DISABLE_SCSI_QCMD(fnic_queuecommand)

/*
* fnic_fcpio_fw_reset_cmpl_handler
--
1.7.3.4