[SCSI] lpfc 8.2.8 v2 : Add sysfs control of target queue depth handling
Added new sysfs attribute lpfc_max_scsicmpl_time. Attribute, when enabled,
will control target queue depth based on I/O completion time.
Signed-off-by: James Smart <james.smart@emulex.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
diff --git a/drivers/scsi/lpfc/lpfc_scsi.c b/drivers/scsi/lpfc/lpfc_scsi.c
index 72eef7e..7b17f52 100644
--- a/drivers/scsi/lpfc/lpfc_scsi.c
+++ b/drivers/scsi/lpfc/lpfc_scsi.c
@@ -628,6 +628,7 @@
lpfc_cmd->result = pIocbOut->iocb.un.ulpWord[4];
lpfc_cmd->status = pIocbOut->iocb.ulpStatus;
+ atomic_dec(&pnode->cmd_pending);
if (lpfc_cmd->status) {
if (lpfc_cmd->status == IOSTAT_LOCAL_REJECT &&
@@ -688,6 +689,29 @@
result = cmd->result;
sdev = cmd->device;
+ if (vport->cfg_max_scsicmpl_time &&
+ time_after(jiffies, lpfc_cmd->start_time +
+ msecs_to_jiffies(vport->cfg_max_scsicmpl_time))) {
+ spin_lock_irqsave(sdev->host->host_lock, flags);
+ if ((pnode->cmd_qdepth > atomic_read(&pnode->cmd_pending) &&
+ (atomic_read(&pnode->cmd_pending) > LPFC_MIN_TGT_QDEPTH) &&
+ ((cmd->cmnd[0] == READ_10) || (cmd->cmnd[0] == WRITE_10))))
+ pnode->cmd_qdepth = atomic_read(&pnode->cmd_pending);
+
+ pnode->last_change_time = jiffies;
+ spin_unlock_irqrestore(sdev->host->host_lock, flags);
+ } else if ((pnode->cmd_qdepth < LPFC_MAX_TGT_QDEPTH) &&
+ time_after(jiffies, pnode->last_change_time +
+ msecs_to_jiffies(LPFC_TGTQ_INTERVAL))) {
+ spin_lock_irqsave(sdev->host->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;
+ pnode->last_change_time = jiffies;
+ spin_unlock_irqrestore(sdev->host->host_lock, flags);
+ }
+
lpfc_scsi_unprep_dma_buf(phba, lpfc_cmd);
cmd->scsi_done(cmd);
@@ -1075,6 +1099,8 @@
cmnd->result = ScsiResult(DID_TRANSPORT_DISRUPTED, 0);
goto out_fail_command;
}
+ if (atomic_read(&ndlp->cmd_pending) >= ndlp->cmd_qdepth)
+ goto out_host_busy;
lpfc_cmd = lpfc_get_scsi_buf(phba);
if (lpfc_cmd == NULL) {
@@ -1093,6 +1119,7 @@
lpfc_cmd->pCmd = cmnd;
lpfc_cmd->rdata = rdata;
lpfc_cmd->timeout = 0;
+ lpfc_cmd->start_time = jiffies;
cmnd->host_scribble = (unsigned char *)lpfc_cmd;
cmnd->scsi_done = done;
@@ -1102,6 +1129,7 @@
lpfc_scsi_prep_cmnd(vport, lpfc_cmd, ndlp);
+ atomic_inc(&ndlp->cmd_pending);
err = lpfc_sli_issue_iocb(phba, &phba->sli.ring[psli->fcp_ring],
&lpfc_cmd->cur_iocbq, SLI_IOCB_RET_IOCB);
if (err)
@@ -1116,6 +1144,7 @@
return 0;
out_host_busy_free_buf:
+ atomic_dec(&ndlp->cmd_pending);
lpfc_scsi_unprep_dma_buf(phba, lpfc_cmd);
lpfc_release_scsi_buf(phba, lpfc_cmd);
out_host_busy: