[PATCH] lpfc 8.1.3: Fix performance when using multiple SLI rings

Fix performance when using multiple SLI rings

Currently the driver allocates all of its SLI command and response ring
entries to one primary ring. Other rings get little, or no, resources.

Allow more resources to be given to ring 1

Signed-off-by: Jamie Wellnitz <Jamie.Wellnitz@emulex.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/drivers/scsi/lpfc/lpfc_attr.c b/drivers/scsi/lpfc/lpfc_attr.c
index ab49379b6abe..2558156f064d 100644
--- a/drivers/scsi/lpfc/lpfc_attr.c
+++ b/drivers/scsi/lpfc/lpfc_attr.c
@@ -671,6 +671,14 @@ LPFC_ATTR_RW(cr_count, 1, 1, 255, "A count of I/O completions after which an "
                 "interrupt response is generated");
 
 /*
+# lpfc_multi_ring_support:  Determines how many rings to spread available
+# cmd/rsp IOCB entries across.
+# Value range is [1,2]. Default value is 1.
+*/
+LPFC_ATTR_R(multi_ring_support, 1, 1, 2, "Determines number of primary "
+                "SLI rings to spread IOCB entries across");
+
+/*
 # lpfc_fdmi_on: controls FDMI support.
 #       0 = no FDMI support
 #       1 = support FDMI without attribute of hostname
@@ -726,6 +734,7 @@ struct class_device_attribute *lpfc_host_attrs[] = {
         &class_device_attr_lpfc_link_speed,
         &class_device_attr_lpfc_cr_delay,
         &class_device_attr_lpfc_cr_count,
+        &class_device_attr_lpfc_multi_ring_support,
         &class_device_attr_lpfc_fdmi_on,
         &class_device_attr_lpfc_max_luns,
         &class_device_attr_nport_evt_cnt,
@@ -1440,6 +1449,7 @@ lpfc_get_cfgparam(struct lpfc_hba *phba)
         lpfc_log_verbose_init(phba, lpfc_log_verbose);
         lpfc_cr_delay_init(phba, lpfc_cr_delay);
         lpfc_cr_count_init(phba, lpfc_cr_count);
+        lpfc_multi_ring_support_init(phba, lpfc_multi_ring_support);
         lpfc_lun_queue_depth_init(phba, lpfc_lun_queue_depth);
         lpfc_fcp_class_init(phba, lpfc_fcp_class);
         lpfc_use_adisc_init(phba, lpfc_use_adisc);