qla2xxx: Remove dependency on hardware_lock to reduce lock contention.

Sessions management (add, deleted, modify) currently are serialized through the hardware_lock. Hardware_lock is a high traffic lock. This lock is accessed by both the transmit & receive sides. Sessions management is now moved off to another lock call sess_lock. This is done to reduce lock contention and increase traffic throughput. Signed-off-by: Quinn Tran <quinn.tran@qlogic.com> Signed-off-by: Himanshu Madhani <himanshu.madhani@qlogic.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
mariux64 · Jan 7, 2016 · 7560151 · 7560151
1 parent 193b50b
commit 7560151
Show file tree

Hide file tree

Showing 4 changed files with 106 additions and 56 deletions.
diff --git a/drivers/scsi/qla2xxx/qla_def.h b/drivers/scsi/qla2xxx/qla_def.h
@@ -2929,6 +2929,7 @@ struct qlt_hw_data {
 	uint32_t num_qfull_cmds_dropped;
 	spinlock_t q_full_lock;
 	uint32_t leak_exchg_thresh_hold;
+	spinlock_t sess_lock;
 };
 
 #define MAX_QFULL_CMDS_ALLOC	8192

diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c
@@ -2336,6 +2336,7 @@ qla2x00_probe_one(struct pci_dev *pdev, const struct pci_device_id *id)
 	ha->tgt.enable_class_2 = ql2xenableclass2;
 	INIT_LIST_HEAD(&ha->tgt.q_full_list);
 	spin_lock_init(&ha->tgt.q_full_lock);
+	spin_lock_init(&ha->tgt.sess_lock);
 
 	/* Clear our data area */
 	ha->bars = bars;