Default behavior is to use the information from the upper io
stacks to select the hardware queue to use for io submission.
which typically has good cpu affinity.
However, the driver, when used on some variants of the upstream
kernel, has found queuing information to be suboptimal for FCP
or io completion locked on particular cpus.
For command submission situations, the lpfc_fcp_io_sched module
parameter can be set to specify a hardware queue selection policy
that overrides the os stack information.
For io completion situations, rather than queing cq processing
based on the cpu servicing the interrupting event, schedule the
cq processing on the cpu associated with the hardware queue's cq.
Signed-off-by: Dick Kennedy <dick.kennedy@xxxxxxxxxxxx>
Signed-off-by: James Smart <jsmart2021@xxxxxxxxx>
---
drivers/scsi/lpfc/lpfc_attr.c | 11 ++++++-----
drivers/scsi/lpfc/lpfc_hw4.h | 2 +-
drivers/scsi/lpfc/lpfc_nvme.c | 14 +++++++++++---
drivers/scsi/lpfc/lpfc_scsi.c | 3 ++-
drivers/scsi/lpfc/lpfc_sli.c | 2 +-
5 files changed, 21 insertions(+), 11 deletions(-)
diff --git a/drivers/scsi/lpfc/lpfc_attr.c b/drivers/scsi/lpfc/lpfc_attr.c
index 0781d65f79ed..b00373215aa0 100644
--- a/drivers/scsi/lpfc/lpfc_attr.c
+++ b/drivers/scsi/lpfc/lpfc_attr.c
@@ -5275,11 +5275,12 @@ LPFC_ATTR_R(xri_rebalancing, 1, 0, 1, "Enable/Disable XRI rebalancing");
/*
* lpfc_io_sched: Determine scheduling algrithmn for issuing FCP cmds
* range is [0,1]. Default value is 0.
- * For [0], FCP commands are issued to Work Queues ina round robin fashion.
+ * For [0], FCP commands are issued to Work Queues based on upper layer
+ * hardware queue index.
* For [1], FCP commands are issued to a Work Queue associated with the
* current CPU.
*
- * LPFC_FCP_SCHED_ROUND_ROBIN == 0
+ * LPFC_FCP_SCHED_BY_HDWQ == 0
* LPFC_FCP_SCHED_BY_CPU == 1
*
* The driver dynamically sets this to 1 (BY_CPU) if it's able to set up cpu
@@ -5287,11 +5288,11 @@ LPFC_ATTR_R(xri_rebalancing, 1, 0, 1, "Enable/Disable XRI rebalancing");
* CPU. Otherwise, the default 0 (Round Robin) scheduling of FCP/NVME I/Os
* through WQs will be used.
*/
-LPFC_ATTR_RW(fcp_io_sched, LPFC_FCP_SCHED_ROUND_ROBIN,
- LPFC_FCP_SCHED_ROUND_ROBIN,
+LPFC_ATTR_RW(fcp_io_sched, LPFC_FCP_SCHED_BY_HDWQ,
+ LPFC_FCP_SCHED_BY_HDWQ,
LPFC_FCP_SCHED_BY_CPU,
"Determine scheduling algorithm for "
- "issuing commands [0] - Round Robin, [1] - Current CPU");
+ "issuing commands [0] - Hardware Queue, [1] - Current CPU");
/*
* lpfc_ns_query: Determine algrithmn for NameServer queries after RSCN
diff --git a/drivers/scsi/lpfc/lpfc_hw4.h b/drivers/scsi/lpfc/lpfc_hw4.h
index c15b9b6fb840..cd39845c909f 100644
--- a/drivers/scsi/lpfc/lpfc_hw4.h
+++ b/drivers/scsi/lpfc/lpfc_hw4.h
@@ -194,7 +194,7 @@ struct lpfc_sli_intf {
#define LPFC_ACT_INTR_CNT 4
/* Algrithmns for scheduling FCP commands to WQs */
-#define LPFC_FCP_SCHED_ROUND_ROBIN 0
+#define LPFC_FCP_SCHED_BY_HDWQ 0
#define LPFC_FCP_SCHED_BY_CPU 1
/* Algrithmns for NameServer Query after RSCN */
diff --git a/drivers/scsi/lpfc/lpfc_nvme.c b/drivers/scsi/lpfc/lpfc_nvme.c
index 0c6c91d39e2f..c9aacd56a449 100644
--- a/drivers/scsi/lpfc/lpfc_nvme.c
+++ b/drivers/scsi/lpfc/lpfc_nvme.c
@@ -1546,8 +1546,17 @@ lpfc_nvme_fcp_io_submit(struct nvme_fc_local_port *pnvme_lport,
}
}
- lpfc_ncmd = lpfc_get_nvme_buf(phba, ndlp,
- lpfc_queue_info->index, expedite);
+ if (phba->cfg_fcp_io_sched == LPFC_FCP_SCHED_BY_HDWQ) {
+ idx = lpfc_queue_info->index;
+ } else {
+ cpu = smp_processor_id();
+ if (cpu < phba->cfg_hdw_queue)
+ idx = cpu;
+ else
+ idx = cpu % phba->cfg_hdw_queue;
+ }
+
+ lpfc_ncmd = lpfc_get_nvme_buf(phba, ndlp, idx, expedite);
if (lpfc_ncmd == NULL) {
atomic_inc(&lport->xmt_fcp_noxri);
lpfc_printf_vlog(vport, KERN_INFO, LOG_NVME_IOERR,
@@ -1585,7 +1594,6 @@ lpfc_nvme_fcp_io_submit(struct nvme_fc_local_port *pnvme_lport,
* index to use and that they have affinitized a CPU to this hardware
* queue. A hardware queue maps to a driver MSI-X vector/EQ/CQ/WQ.
*/
- idx = lpfc_queue_info->index;
lpfc_ncmd->cur_iocbq.hba_wqidx = idx;
cstat = &phba->sli4_hba.hdwq[idx].nvme_cstat;
diff --git a/drivers/scsi/lpfc/lpfc_scsi.c b/drivers/scsi/lpfc/lpfc_scsi.c
index 484ac9493fd0..80d19b0d3306 100644
--- a/drivers/scsi/lpfc/lpfc_scsi.c
+++ b/drivers/scsi/lpfc/lpfc_scsi.c
@@ -689,7 +689,8 @@ lpfc_get_scsi_buf_s4(struct lpfc_hba *phba, struct lpfc_nodelist *ndlp,
cpu = smp_processor_id();
if (cmnd && shost_use_blk_mq(cmnd->device->host) &&
- phba->cfg_enable_scsi_mq) {
+ phba->cfg_enable_scsi_mq &&
+ (phba->cfg_fcp_io_sched == LPFC_FCP_SCHED_BY_HDWQ)) {
tag = blk_mq_unique_tag(cmnd->request);
idx = blk_mq_unique_tag_to_hwq(tag);
} else {
diff --git a/drivers/scsi/lpfc/lpfc_sli.c b/drivers/scsi/lpfc/lpfc_sli.c
index 280a1c7d162c..b0113a56efdc 100644
--- a/drivers/scsi/lpfc/lpfc_sli.c
+++ b/drivers/scsi/lpfc/lpfc_sli.c
@@ -14107,7 +14107,7 @@ lpfc_sli4_hba_handle_eqe(struct lpfc_hba *phba, struct lpfc_eqe *eqe,
/* Save EQ associated with this CQ */
cq->assoc_qp = phba->sli4_hba.hdwq[qidx].hba_eq;
- if (!queue_work(phba->wq, &cq->irqwork))
+ if (!queue_work_on(cq->chann, phba->wq, &cq->irqwork))
lpfc_printf_log(phba, KERN_ERR, LOG_SLI,
"0363 Cannot schedule soft IRQ "
"for CQ eqcqid=%d, cqid=%d on CPU %d\n",
--
2.13.7
