diff options
| author | Dick Kennedy <dick.kennedy@broadcom.com> | 2017-09-29 17:34:33 -0700 |
|---|---|---|
| committer | Martin K. Petersen <martin.petersen@oracle.com> | 2017-10-02 22:46:35 -0400 |
| commit | c8a4ce0bf3aad1a73d5122a3781a0be83bc0d0a4 (patch) | |
| tree | e75c5208cf24295adf7355d815aab0714d4994fe /drivers/scsi/lpfc/lpfc_nvme.c | |
| parent | e8bcf0ae4c0346fdc78ebefe0eefcaa6a6622d38 (diff) | |
scsi: lpfc: Make ktime sampling more accurate
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>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'drivers/scsi/lpfc/lpfc_nvme.c')
| -rw-r--r-- | drivers/scsi/lpfc/lpfc_nvme.c | 34 |
1 files changed, 23 insertions, 11 deletions
diff --git a/drivers/scsi/lpfc/lpfc_nvme.c b/drivers/scsi/lpfc/lpfc_nvme.c index 1942e61e1103..68074bf73b6c 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 @@ out_err: * 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) { |