[SCSI] lpfc 8.3.15: Add target queue depth throttling

Signed-off-by: Alex Iannicelli <alex.iannicelli@emulex.com>
Signed-off-by: James Smart <james.smart@emulex.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

4 files changed, 22 insertions, 10 deletions

diff --git a/drivers/scsi/lpfc/lpfc.h b/drivers/scsi/lpfc/lpfc.h
index bb40fcbe17c5..3482d5a5aed2 100644
--- a/drivers/scsi/lpfc/lpfc.h
+++ b/drivers/scsi/lpfc/lpfc.h
@@ -48,7 +48,7 @@ struct lpfc_sli2_slim;
 #define LPFC_TGTQ_INTERVAL      40000   /* Min amount of time between tgt
                                            queue depth change in millisecs */
 #define LPFC_TGTQ_RAMPUP_PCENT  5       /* Target queue rampup in percentage */
-#define LPFC_MIN_TGT_QDEPTH     100
+#define LPFC_MIN_TGT_QDEPTH     10
 #define LPFC_MAX_TGT_QDEPTH     0xFFFF
 
 #define  LPFC_MAX_BUCKET_COUNT 20       /* Maximum no. of buckets for stat data
@@ -400,6 +400,7 @@ struct lpfc_vport {
         uint32_t cfg_max_luns;
         uint32_t cfg_enable_da_id;
         uint32_t cfg_max_scsicmpl_time;
+        uint32_t cfg_tgt_queue_depth;
 
         uint32_t dev_loss_tmo_changed;
 
diff --git a/drivers/scsi/lpfc/lpfc_attr.c b/drivers/scsi/lpfc/lpfc_attr.c
index a7c6b7390554..868874c28f99 100644
--- a/drivers/scsi/lpfc/lpfc_attr.c
+++ b/drivers/scsi/lpfc/lpfc_attr.c
@@ -2208,6 +2208,13 @@ LPFC_VPORT_ATTR_R(lun_queue_depth, 30, 1, 128,
                   "Max number of FCP commands we can queue to a specific LUN");
 
 /*
+# tgt_queue_depth:  This parameter is used to limit the number of outstanding
+# commands per target port. Value range is [10,65535]. Default value is 65535.
+*/
+LPFC_VPORT_ATTR_R(tgt_queue_depth, 65535, 10, 65535,
+        "Max number of FCP commands we can queue to a specific target port");
+
+/*
 # hba_queue_depth:  This parameter is used to limit the number of outstanding
 # commands per lpfc HBA. Value range is [32,8192]. If this parameter
 # value is greater than the maximum number of exchanges supported by the HBA,
@@ -3122,7 +3129,7 @@ lpfc_max_scsicmpl_time_set(struct lpfc_vport *vport, int val)
                         continue;
                 if (ndlp->nlp_state == NLP_STE_UNUSED_NODE)
                         continue;
-                ndlp->cmd_qdepth = LPFC_MAX_TGT_QDEPTH;
+                ndlp->cmd_qdepth = vport->cfg_tgt_queue_depth;
         }
         spin_unlock_irq(shost->host_lock);
         return 0;
@@ -3326,6 +3333,7 @@ struct device_attribute *lpfc_hba_attrs[] = {
         &dev_attr_lpfc_temp_sensor,
         &dev_attr_lpfc_log_verbose,
         &dev_attr_lpfc_lun_queue_depth,
+        &dev_attr_lpfc_tgt_queue_depth,
         &dev_attr_lpfc_hba_queue_depth,
         &dev_attr_lpfc_peer_port_login,
         &dev_attr_lpfc_nodev_tmo,
@@ -3387,6 +3395,7 @@ struct device_attribute *lpfc_vport_attrs[] = {
         &dev_attr_lpfc_drvr_version,
         &dev_attr_lpfc_log_verbose,
         &dev_attr_lpfc_lun_queue_depth,
+        &dev_attr_lpfc_tgt_queue_depth,
         &dev_attr_lpfc_nodev_tmo,
         &dev_attr_lpfc_devloss_tmo,
         &dev_attr_lpfc_hba_queue_depth,
@@ -4575,6 +4584,7 @@ lpfc_get_vport_cfgparam(struct lpfc_vport *vport)
 {
         lpfc_log_verbose_init(vport, lpfc_log_verbose);
         lpfc_lun_queue_depth_init(vport, lpfc_lun_queue_depth);
+        lpfc_tgt_queue_depth_init(vport, lpfc_tgt_queue_depth);
         lpfc_devloss_tmo_init(vport, lpfc_devloss_tmo);
         lpfc_nodev_tmo_init(vport, lpfc_nodev_tmo);
         lpfc_peer_port_login_init(vport, lpfc_peer_port_login);
diff --git a/drivers/scsi/lpfc/lpfc_hbadisc.c b/drivers/scsi/lpfc/lpfc_hbadisc.c
index 92498e488f4f..0639c994349c 100644
--- a/drivers/scsi/lpfc/lpfc_hbadisc.c
+++ b/drivers/scsi/lpfc/lpfc_hbadisc.c
@@ -3583,7 +3583,7 @@ lpfc_initialize_node(struct lpfc_vport *vport, struct lpfc_nodelist *ndlp,
         kref_init(&ndlp->kref);
         NLP_INT_NODE_ACT(ndlp);
         atomic_set(&ndlp->cmd_pending, 0);
-        ndlp->cmd_qdepth = LPFC_MAX_TGT_QDEPTH;
+        ndlp->cmd_qdepth = vport->cfg_tgt_queue_depth;
 }
 
 struct lpfc_nodelist *
diff --git a/drivers/scsi/lpfc/lpfc_scsi.c b/drivers/scsi/lpfc/lpfc_scsi.c
index d6089c985c3f..c818a7255962 100644
--- a/drivers/scsi/lpfc/lpfc_scsi.c
+++ b/drivers/scsi/lpfc/lpfc_scsi.c
@@ -2458,14 +2458,16 @@ lpfc_scsi_cmd_iocb_cmpl(struct lpfc_hba *phba, struct lpfc_iocbq *pIocbIn,
                 }
                 spin_unlock_irqrestore(shost->host_lock, flags);
         } else if (pnode && NLP_CHK_NODE_ACT(pnode)) {
-                if ((pnode->cmd_qdepth < LPFC_MAX_TGT_QDEPTH) &&
+                if ((pnode->cmd_qdepth < vport->cfg_tgt_queue_depth) &&
                    time_after(jiffies, pnode->last_change_time +
                               msecs_to_jiffies(LPFC_TGTQ_INTERVAL))) {
                         spin_lock_irqsave(shost->host_lock, flags);
-                        pnode->cmd_qdepth += pnode->cmd_qdepth *
-                                LPFC_TGTQ_RAMPUP_PCENT / 100;
-                        if (pnode->cmd_qdepth > LPFC_MAX_TGT_QDEPTH)
-                                pnode->cmd_qdepth = LPFC_MAX_TGT_QDEPTH;
+                        depth = pnode->cmd_qdepth * LPFC_TGTQ_RAMPUP_PCENT
+                                / 100;
+                        depth = depth ? depth : 1;
+                        pnode->cmd_qdepth += depth;
+                        if (pnode->cmd_qdepth > vport->cfg_tgt_queue_depth)
+                                pnode->cmd_qdepth = vport->cfg_tgt_queue_depth;
                         pnode->last_change_time = jiffies;
                         spin_unlock_irqrestore(shost->host_lock, flags);
                 }
@@ -2920,8 +2922,7 @@ lpfc_queuecommand(struct scsi_cmnd *cmnd, void (*done) (struct scsi_cmnd *))
                 cmnd->result = ScsiResult(DID_TRANSPORT_DISRUPTED, 0);
                 goto out_fail_command;
         }
-        if (vport->cfg_max_scsicmpl_time &&
-                (atomic_read(&ndlp->cmd_pending) >= ndlp->cmd_qdepth))
+        if (atomic_read(&ndlp->cmd_pending) >= ndlp->cmd_qdepth)
                 goto out_host_busy;
 
         lpfc_cmd = lpfc_get_scsi_buf(phba);