[PATCH v2 07/21] lpfc: Make ktime sampling more accurate

James Smart
2017-09-30T00:35:02Z

Need to make ktime samples more accurate

If ktime is turned on in the middle of an IO, the max calculation
could be misleading. Base sampling on the start time of the IO
as opposed to ktime_on.

Make ISR ktime timestamps be from when CQE is read instead of EQE.
Added additional sanity checks when deciding whether to accept an
IO sample or not.

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <james.smart@broadcom.com>
---
drivers/scsi/lpfc/lpfc_nvme.c | 34 ++++++++++-----
drivers/scsi/lpfc/lpfc_nvmet.c | 99 ++++++++++++++++++++++++++++--------------
drivers/scsi/lpfc/lpfc_sli.c | 34 +++++++++------
3 files changed, 109 insertions(+), 58 deletions(-)

diff --git a/drivers/scsi/lpfc/lpfc_nvme.c b/drivers/scsi/lpfc/lpfc_nvme.c
index 2ad23b356bfe..a83b57254de6 100644
--- a/drivers/scsi/lpfc/lpfc_nvme.c
+++ b/drivers/scsi/lpfc/lpfc_nvme.c
@@ -667,15 +667,17 @@ lpfc_nvme_ktime(struct lpfc_hba *phba,
struct lpfc_nvme_buf *lpfc_ncmd)
{
uint64_t seg1, seg2, seg3, seg4;
+ uint64_t segsum;

- if (!phba->ktime_on)
- return;
if (!lpfc_ncmd->ts_last_cmd ||
!lpfc_ncmd->ts_cmd_start ||
!lpfc_ncmd->ts_cmd_wqput ||
!lpfc_ncmd->ts_isr_cmpl ||
!lpfc_ncmd->ts_data_nvme)
return;
+
+ if (lpfc_ncmd->ts_data_nvme < lpfc_ncmd->ts_cmd_start)
+ return;
if (lpfc_ncmd->ts_cmd_start < lpfc_ncmd->ts_last_cmd)
return;
if (lpfc_ncmd->ts_cmd_wqput < lpfc_ncmd->ts_cmd_start)
@@ -695,15 +697,23 @@ lpfc_nvme_ktime(struct lpfc_hba *phba,
* cmpl is handled off to the NVME Layer.
*/
seg1 = lpfc_ncmd->ts_cmd_start - lpfc_ncmd->ts_last_cmd;
- if (seg1 > 5000000) /* 5 ms - for sequential IOs */
- return;
+ if (seg1 > 5000000) /* 5 ms - for sequential IOs only */
+ seg1 = 0;

/* Calculate times relative to start of IO */
seg2 = (lpfc_ncmd->ts_cmd_wqput - lpfc_ncmd->ts_cmd_start);
- seg3 = (lpfc_ncmd->ts_isr_cmpl -
- lpfc_ncmd->ts_cmd_start) - seg2;
- seg4 = (lpfc_ncmd->ts_data_nvme -
- lpfc_ncmd->ts_cmd_start) - seg2 - seg3;
+ segsum = seg2;
+ seg3 = lpfc_ncmd->ts_isr_cmpl - lpfc_ncmd->ts_cmd_start;
+ if (segsum > seg3)
+ return;
+ seg3 -= segsum;
+ segsum += seg3;
+
+ seg4 = lpfc_ncmd->ts_data_nvme - lpfc_ncmd->ts_cmd_start;
+ if (segsum > seg4)
+ return;
+ seg4 -= segsum;
+
phba->ktime_data_samples++;
phba->ktime_seg1_total += seg1;
if (seg1 < phba->ktime_seg1_min)
@@ -902,7 +912,7 @@ lpfc_nvme_io_cmd_wqe_cmpl(struct lpfc_hba *phba, struct lpfc_iocbq *pwqeIn,
* owns the dma address.
*/
#ifdef CONFIG_SCSI_LPFC_DEBUG_FS
- if (phba->ktime_on) {
+ if (lpfc_ncmd->ts_cmd_start) {
lpfc_ncmd->ts_isr_cmpl = pwqeIn->isr_timestamp;
lpfc_ncmd->ts_data_nvme = ktime_get_ns();
phba->ktime_last_cmd = lpfc_ncmd->ts_data_nvme;
@@ -1283,9 +1293,11 @@ lpfc_nvme_fcp_io_submit(struct nvme_fc_local_port *pnvme_lport,
goto out_fail;
}
#ifdef CONFIG_SCSI_LPFC_DEBUG_FS
- if (phba->ktime_on) {
+ if (start) {
lpfc_ncmd->ts_cmd_start = start;
lpfc_ncmd->ts_last_cmd = phba->ktime_last_cmd;
+ } else {
+ lpfc_ncmd->ts_cmd_start = 0;
}
#endif

@@ -1336,7 +1348,7 @@ lpfc_nvme_fcp_io_submit(struct nvme_fc_local_port *pnvme_lport,
}

#ifdef CONFIG_SCSI_LPFC_DEBUG_FS
- if (phba->ktime_on)
+ if (lpfc_ncmd->ts_cmd_start)
lpfc_ncmd->ts_cmd_wqput = ktime_get_ns();

if (phba->cpucheck_on & LPFC_CHECK_NVME_IO) {
diff --git a/drivers/scsi/lpfc/lpfc_nvmet.c b/drivers/scsi/lpfc/lpfc_nvmet.c
index b6cd213567ac..cee88f3c0779 100644
--- a/drivers/scsi/lpfc/lpfc_nvmet.c
+++ b/drivers/scsi/lpfc/lpfc_nvmet.c
@@ -221,9 +221,8 @@ lpfc_nvmet_ctxbuf_post(struct lpfc_hba *phba, struct lpfc_nvmet_ctxbuf *ctx_buf)
spin_lock_init(&ctxp->ctxlock);

#ifdef CONFIG_SCSI_LPFC_DEBUG_FS
- if (phba->ktime_on) {
+ if (ctxp->ts_cmd_nvme) {
ctxp->ts_cmd_nvme = ktime_get_ns();
- ctxp->ts_isr_cmd = ctxp->ts_cmd_nvme;
ctxp->ts_nvme_data = 0;
ctxp->ts_data_wqput = 0;
ctxp->ts_isr_data = 0;
@@ -289,9 +288,7 @@ lpfc_nvmet_ktime(struct lpfc_hba *phba,
{
uint64_t seg1, seg2, seg3, seg4, seg5;
uint64_t seg6, seg7, seg8, seg9, seg10;
-
- if (!phba->ktime_on)
- return;
+ uint64_t segsum;

if (!ctxp->ts_isr_cmd || !ctxp->ts_cmd_nvme ||
!ctxp->ts_nvme_data || !ctxp->ts_data_wqput ||
@@ -300,6 +297,8 @@ lpfc_nvmet_ktime(struct lpfc_hba *phba,
!ctxp->ts_isr_status || !ctxp->ts_status_nvme)
return;

+ if (ctxp->ts_status_nvme < ctxp->ts_isr_cmd)
+ return;
if (ctxp->ts_isr_cmd > ctxp->ts_cmd_nvme)
return;
if (ctxp->ts_cmd_nvme > ctxp->ts_nvme_data)
@@ -344,34 +343,66 @@ lpfc_nvmet_ktime(struct lpfc_hba *phba,
* (Segments 1 thru 4) for READDATA_RSP
*/
seg1 = ctxp->ts_cmd_nvme - ctxp->ts_isr_cmd;
- seg2 = (ctxp->ts_nvme_data - ctxp->ts_isr_cmd) - seg1;
- seg3 = (ctxp->ts_data_wqput - ctxp->ts_isr_cmd) -
- seg1 - seg2;
- seg4 = (ctxp->ts_isr_data - ctxp->ts_isr_cmd) -
- seg1 - seg2 - seg3;
- seg5 = (ctxp->ts_data_nvme - ctxp->ts_isr_cmd) -
- seg1 - seg2 - seg3 - seg4;
+ segsum = seg1;
+
+ seg2 = ctxp->ts_nvme_data - ctxp->ts_isr_cmd;
+ if (segsum > seg2)
+ return;
+ seg2 -= segsum;
+ segsum += seg2;
+
+ seg3 = ctxp->ts_data_wqput - ctxp->ts_isr_cmd;
+ if (segsum > seg3)
+ return;
+ seg3 -= segsum;
+ segsum += seg3;
+
+ seg4 = ctxp->ts_isr_data - ctxp->ts_isr_cmd;
+ if (segsum > seg4)
+ return;
+ seg4 -= segsum;
+ segsum += seg4;
+
+ seg5 = ctxp->ts_data_nvme - ctxp->ts_isr_cmd;
+ if (segsum > seg5)
+ return;
+ seg5 -= segsum;
+ segsum += seg5;
+

/* For auto rsp commands seg6 thru seg10 will be 0 */
if (ctxp->ts_nvme_status > ctxp->ts_data_nvme) {
- seg6 = (ctxp->ts_nvme_status -
- ctxp->ts_isr_cmd) -
- seg1 - seg2 - seg3 - seg4 - seg5;
- seg7 = (ctxp->ts_status_wqput -
- ctxp->ts_isr_cmd) -
- seg1 - seg2 - seg3 -
- seg4 - seg5 - seg6;
- seg8 = (ctxp->ts_isr_status -
- ctxp->ts_isr_cmd) -
- seg1 - seg2 - seg3 - seg4 -
- seg5 - seg6 - seg7;
- seg9 = (ctxp->ts_status_nvme -
- ctxp->ts_isr_cmd) -
- seg1 - seg2 - seg3 - seg4 -
- seg5 - seg6 - seg7 - seg8;
+ seg6 = ctxp->ts_nvme_status - ctxp->ts_isr_cmd;
+ if (segsum > seg6)
+ return;
+ seg6 -= segsum;
+ segsum += seg6;
+
+ seg7 = ctxp->ts_status_wqput - ctxp->ts_isr_cmd;
+ if (segsum > seg7)
+ return;
+ seg7 -= segsum;
+ segsum += seg7;
+
+ seg8 = ctxp->ts_isr_status - ctxp->ts_isr_cmd;
+ if (segsum > seg8)
+ return;
+ seg8 -= segsum;
+ segsum += seg8;
+
+ seg9 = ctxp->ts_status_nvme - ctxp->ts_isr_cmd;
+ if (segsum > seg9)
+ return;
+ seg9 -= segsum;
+ segsum += seg9;
+
+ if (ctxp->ts_isr_status < ctxp->ts_isr_cmd)
+ return;
seg10 = (ctxp->ts_isr_status -
ctxp->ts_isr_cmd);
} else {
+ if (ctxp->ts_isr_data < ctxp->ts_isr_cmd)
+ return;
seg6 = 0;
seg7 = 0;
seg8 = 0;
@@ -519,7 +550,7 @@ lpfc_nvmet_xmt_fcp_op_cmp(struct lpfc_hba *phba, struct lpfc_iocbq *cmdwqe,
ctxp->entry_cnt++;

#ifdef CONFIG_SCSI_LPFC_DEBUG_FS
- if (phba->ktime_on) {
+ if (ctxp->ts_cmd_nvme) {
if (rsp->op == NVMET_FCOP_READDATA_RSP) {
ctxp->ts_isr_data =
cmdwqe->isr_timestamp;
@@ -553,7 +584,7 @@ lpfc_nvmet_xmt_fcp_op_cmp(struct lpfc_hba *phba, struct lpfc_iocbq *cmdwqe,
#endif
rsp->done(rsp);
#ifdef CONFIG_SCSI_LPFC_DEBUG_FS
- if (phba->ktime_on)
+ if (ctxp->ts_cmd_nvme)
lpfc_nvmet_ktime(phba, ctxp);
#endif
/* lpfc_nvmet_xmt_fcp_release() will recycle the context */
@@ -563,7 +594,7 @@ lpfc_nvmet_xmt_fcp_op_cmp(struct lpfc_hba *phba, struct lpfc_iocbq *cmdwqe,
memset(((char *)cmdwqe) + start_clean, 0,
(sizeof(struct lpfc_iocbq) - start_clean));
#ifdef CONFIG_SCSI_LPFC_DEBUG_FS
- if (phba->ktime_on) {
+ if (ctxp->ts_cmd_nvme) {
ctxp->ts_isr_data = cmdwqe->isr_timestamp;
ctxp->ts_data_nvme = ktime_get_ns();
}
@@ -679,7 +710,7 @@ lpfc_nvmet_xmt_fcp_op(struct nvmet_fc_target_port *tgtport,
int rc;

#ifdef CONFIG_SCSI_LPFC_DEBUG_FS
- if (phba->ktime_on) {
+ if (ctxp->ts_cmd_nvme) {
if (rsp->op == NVMET_FCOP_RSP)
ctxp->ts_nvme_status = ktime_get_ns();
else
@@ -734,7 +765,7 @@ lpfc_nvmet_xmt_fcp_op(struct nvmet_fc_target_port *tgtport,
rc = lpfc_sli4_issue_wqe(phba, LPFC_FCP_RING, nvmewqeq);
if (rc == WQE_SUCCESS) {
#ifdef CONFIG_SCSI_LPFC_DEBUG_FS
- if (!phba->ktime_on)
+ if (!ctxp->ts_cmd_nvme)
return 0;
if (rsp->op == NVMET_FCOP_RSP)
ctxp->ts_status_wqput = ktime_get_ns();
@@ -1614,7 +1645,7 @@ lpfc_nvmet_unsol_fcp_buffer(struct lpfc_hba *phba,
spin_lock_init(&ctxp->ctxlock);

#ifdef CONFIG_SCSI_LPFC_DEBUG_FS
- if (phba->ktime_on) {
+ if (isr_timestamp) {
ctxp->ts_isr_cmd = isr_timestamp;
ctxp->ts_cmd_nvme = ktime_get_ns();
ctxp->ts_nvme_data = 0;
@@ -1625,6 +1656,8 @@ lpfc_nvmet_unsol_fcp_buffer(struct lpfc_hba *phba,
ctxp->ts_status_wqput = 0;
ctxp->ts_isr_status = 0;
ctxp->ts_status_nvme = 0;
+ } else {
+ ctxp->ts_cmd_nvme = 0;
}
#endif

diff --git a/drivers/scsi/lpfc/lpfc_sli.c b/drivers/scsi/lpfc/lpfc_sli.c
index 9024521b97c7..3ace438d8f2e 100644
--- a/drivers/scsi/lpfc/lpfc_sli.c
+++ b/drivers/scsi/lpfc/lpfc_sli.c
@@ -13064,13 +13064,20 @@ lpfc_sli4_sp_handle_eqe(struct lpfc_hba *phba, struct lpfc_eqe *eqe,
break;
case LPFC_WCQ:
while ((cqe = lpfc_sli4_cq_get(cq))) {
- if ((cq->subtype == LPFC_FCP) ||
- (cq->subtype == LPFC_NVME))
+ if (cq->subtype == LPFC_FCP ||
+ cq->subtype == LPFC_NVME) {
+#ifdef CONFIG_SCSI_LPFC_DEBUG_FS
+ if (phba->ktime_on)
+ cq->isr_timestamp = ktime_get_ns();
+ else
+ cq->isr_timestamp = 0;
+#endif
workposted |= lpfc_sli4_fp_handle_cqe(phba, cq,
cqe);
- else
+ } else {
workposted |= lpfc_sli4_sp_handle_cqe(phba, cq,
cqe);
+ }
if (!(++ecount % cq->entry_repost))
break;
}
@@ -13155,11 +13162,9 @@ lpfc_sli4_fp_handle_fcp_wcqe(struct lpfc_hba *phba, struct lpfc_queue *cq,
bf_get(lpfc_wcqe_c_request_tag, wcqe));
return;
}
-
- if (cq->assoc_qp)
- cmdiocbq->isr_timestamp =
- cq->assoc_qp->isr_timestamp;
-
+#ifdef CONFIG_SCSI_LPFC_DEBUG_FS
+ cmdiocbq->isr_timestamp = cq->isr_timestamp;
+#endif
if (cmdiocbq->iocb_cmpl == NULL) {
if (cmdiocbq->wqe_cmpl) {
if (cmdiocbq->iocb_flag & LPFC_DRIVER_ABORTED) {
@@ -13304,7 +13309,7 @@ lpfc_sli4_nvmet_handle_rcqe(struct lpfc_hba *phba, struct lpfc_queue *cq,
dma_buf->bytes_recv = bf_get(lpfc_rcqe_length, rcqe);
lpfc_nvmet_unsol_fcp_event(
phba, idx, dma_buf,
- cq->assoc_qp->isr_timestamp);
+ cq->isr_timestamp);
return false;
}
drop:
@@ -13479,6 +13484,12 @@ lpfc_sli4_hba_handle_eqe(struct lpfc_hba *phba, struct lpfc_eqe *eqe,

/* Process all the entries to the CQ */
while ((cqe = lpfc_sli4_cq_get(cq))) {
+#ifdef CONFIG_SCSI_LPFC_DEBUG_FS
+ if (phba->ktime_on)
+ cq->isr_timestamp = ktime_get_ns();
+ else
+ cq->isr_timestamp = 0;
+#endif
workposted |= lpfc_sli4_fp_handle_cqe(phba, cq, cqe);
if (!(++ecount % cq->entry_repost))
break;
@@ -13741,11 +13752,6 @@ lpfc_sli4_hba_intr_handler(int irq, void *dev_id)
if (unlikely(!fpeq))
return IRQ_NONE;

-#ifdef CONFIG_SCSI_LPFC_DEBUG_FS
- if (phba->ktime_on)
- fpeq->isr_timestamp = ktime_get_ns();
-#endif
-
if (lpfc_fcp_look_ahead) {
if (atomic_dec_and_test(&hba_eq_hdl->hba_eq_in_use))
lpfc_sli4_eq_clr_intr(fpeq);
--
2.13.1