From: James Smart <jsmart2021@gmail.com>
Date: Fri, 10 Sep 2021 16:31:58 -0700
Subject: scsi: lpfc: Improve PBDE checks during SGL processing
Patch-mainline: v5.16-rc1
Git-commit: 315b3fd13521fb44d97572eb24b7c8670ec7fd97
References: bsc#1190576
The PBDE feature, setting payload buffer address explicitly in the WQE so
it doesn't have to be fetched from the SGL, only makes sense when there is
a single buffer for the I/O. When there are multiple buffers it actually
hurts performance as the SGL subsequently has to be fetched.
Rework the SGL logic to only use PBDE when a single buffer.
Link: https://lore.kernel.org/r/20210910233159.115896-14-jsmart2021@gmail.com
Co-developed-by: Justin Tee <justin.tee@broadcom.com>
Signed-off-by: Justin Tee <justin.tee@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Daniel Wagner <dwagner@suse.de>
---
drivers/scsi/lpfc/lpfc_nvme.c | 12 +++++------
drivers/scsi/lpfc/lpfc_nvmet.c | 44 +++++++++++++++++++----------------------
drivers/scsi/lpfc/lpfc_scsi.c | 26 ++++++++++++------------
3 files changed, 40 insertions(+), 42 deletions(-)
--- a/drivers/scsi/lpfc/lpfc_nvme.c
+++ b/drivers/scsi/lpfc/lpfc_nvme.c
@@ -1149,7 +1149,6 @@ lpfc_nvme_prep_io_dma(struct lpfc_vport
struct sli4_sge *first_data_sgl;
struct ulp_bde64 *bde;
dma_addr_t physaddr = 0;
- uint32_t num_bde = 0;
uint32_t dma_len = 0;
uint32_t dma_offset = 0;
int nseg, i, j;
@@ -1203,7 +1202,7 @@ lpfc_nvme_prep_io_dma(struct lpfc_vport
}
sgl->word2 = 0;
- if ((num_bde + 1) == nseg) {
+ if (nseg == 1) {
bf_set(lpfc_sli4_sge_last, sgl, 1);
bf_set(lpfc_sli4_sge_type, sgl,
LPFC_SGE_TYPE_DATA);
@@ -1272,8 +1271,9 @@ lpfc_nvme_prep_io_dma(struct lpfc_vport
j++;
}
- if (phba->cfg_enable_pbde) {
- /* Use PBDE support for first SGL only, offset == 0 */
+
+ /* PBDE support for first data SGE only */
+ if (nseg == 1 && phba->cfg_enable_pbde) {
/* Words 13-15 */
bde = (struct ulp_bde64 *)
&wqe->words[13];
@@ -1284,11 +1284,11 @@ lpfc_nvme_prep_io_dma(struct lpfc_vport
bde->tus.f.bdeFlags = BUFF_TYPE_BDE_64;
bde->tus.w = cpu_to_le32(bde->tus.w);
- /* Word 11 */
+ /* Word 11 - set PBDE bit */
bf_set(wqe_pbde, &wqe->generic.wqe_com, 1);
} else {
memset(&wqe->words[13], 0, (sizeof(uint32_t) * 3));
- bf_set(wqe_pbde, &wqe->generic.wqe_com, 0);
+ /* Word 11 - PBDE bit disabled by default template */
}
} else {
--- a/drivers/scsi/lpfc/lpfc_nvmet.c
+++ b/drivers/scsi/lpfc/lpfc_nvmet.c
@@ -2567,7 +2567,7 @@ lpfc_nvmet_prep_fcp_wqe(struct lpfc_hba
struct ulp_bde64 *bde;
dma_addr_t physaddr;
int i, cnt, nsegs;
- int do_pbde;
+ bool use_pbde = false;
int xc = 1;
if (!lpfc_is_link_up(phba)) {
@@ -2675,9 +2675,6 @@ lpfc_nvmet_prep_fcp_wqe(struct lpfc_hba
if (!xc)
bf_set(wqe_xc, &wqe->fcp_tsend.wqe_com, 0);
- /* Word 11 - set sup, irsp, irsplen later */
- do_pbde = 0;
-
/* Word 12 */
wqe->fcp_tsend.fcp_data_len = rsp->transfer_length;
@@ -2755,12 +2752,13 @@ lpfc_nvmet_prep_fcp_wqe(struct lpfc_hba
if (!xc)
bf_set(wqe_xc, &wqe->fcp_treceive.wqe_com, 0);
- /* Word 11 - set pbde later */
- if (phba->cfg_enable_pbde) {
- do_pbde = 1;
+ /* Word 11 - check for pbde */
+ if (nsegs == 1 && phba->cfg_enable_pbde) {
+ use_pbde = true;
+ /* Word 11 - PBDE bit already preset by template */
} else {
+ /* Overwrite default template setting */
bf_set(wqe_pbde, &wqe->fcp_treceive.wqe_com, 0);
- do_pbde = 0;
}
/* Word 12 */
@@ -2831,7 +2829,6 @@ lpfc_nvmet_prep_fcp_wqe(struct lpfc_hba
((rsp->rsplen >> 2) - 1));
memcpy(&wqe->words[16], rsp->rspaddr, rsp->rsplen);
}
- do_pbde = 0;
/* Word 12 */
wqe->fcp_trsp.rsvd_12_15[0] = 0;
@@ -2866,23 +2863,24 @@ lpfc_nvmet_prep_fcp_wqe(struct lpfc_hba
bf_set(lpfc_sli4_sge_last, sgl, 1);
sgl->word2 = cpu_to_le32(sgl->word2);
sgl->sge_len = cpu_to_le32(cnt);
- if (i == 0) {
- bde = (struct ulp_bde64 *)&wqe->words[13];
- if (do_pbde) {
- /* Words 13-15 (PBDE) */
- bde->addrLow = sgl->addr_lo;
- bde->addrHigh = sgl->addr_hi;
- bde->tus.f.bdeSize =
- le32_to_cpu(sgl->sge_len);
- bde->tus.f.bdeFlags = BUFF_TYPE_BDE_64;
- bde->tus.w = cpu_to_le32(bde->tus.w);
- } else {
- memset(bde, 0, sizeof(struct ulp_bde64));
- }
- }
sgl++;
ctxp->offset += cnt;
}
+
+ bde = (struct ulp_bde64 *)&wqe->words[13];
+ if (use_pbde) {
+ /* decrement sgl ptr backwards once to first data sge */
+ sgl--;
+
+ /* Words 13-15 (PBDE) */
+ bde->addrLow = sgl->addr_lo;
+ bde->addrHigh = sgl->addr_hi;
+ bde->tus.f.bdeSize = le32_to_cpu(sgl->sge_len);
+ bde->tus.f.bdeFlags = BUFF_TYPE_BDE_64;
+ bde->tus.w = cpu_to_le32(bde->tus.w);
+ } else {
+ memset(bde, 0, sizeof(struct ulp_bde64));
+ }
ctxp->state = LPFC_NVMET_STE_DATA;
ctxp->entry_cnt++;
return nvmewqe;
--- a/drivers/scsi/lpfc/lpfc_scsi.c
+++ b/drivers/scsi/lpfc/lpfc_scsi.c
@@ -3243,7 +3243,6 @@ lpfc_scsi_prep_dma_buf_s4(struct lpfc_hb
struct lpfc_vport *vport = phba->pport;
union lpfc_wqe128 *wqe = &pwqeq->wqe;
dma_addr_t physaddr;
- uint32_t num_bde = 0;
uint32_t dma_len;
uint32_t dma_offset = 0;
int nseg, i, j;
@@ -3305,7 +3304,7 @@ lpfc_scsi_prep_dma_buf_s4(struct lpfc_hb
j = 2;
for (i = 0; i < nseg; i++) {
sgl->word2 = 0;
- if ((num_bde + 1) == nseg) {
+ if (nseg == 1) {
bf_set(lpfc_sli4_sge_last, sgl, 1);
bf_set(lpfc_sli4_sge_type, sgl,
LPFC_SGE_TYPE_DATA);
@@ -3374,13 +3373,15 @@ lpfc_scsi_prep_dma_buf_s4(struct lpfc_hb
j++;
}
- /*
- * Setup the first Payload BDE. For FCoE we just key off
- * Performance Hints, for FC we use lpfc_enable_pbde.
- * We populate words 13-15 of IOCB/WQE.
+
+ /* PBDE support for first data SGE only.
+ * For FCoE, we key off Performance Hints.
+ * For FC, we key off lpfc_enable_pbde.
*/
- if ((phba->sli3_options & LPFC_SLI4_PERFH_ENABLED) ||
- phba->cfg_enable_pbde) {
+ if (nseg == 1 &&
+ ((phba->sli3_options & LPFC_SLI4_PERFH_ENABLED) ||
+ phba->cfg_enable_pbde)) {
+ /* Words 13-15 */
bde = (struct ulp_bde64 *)
&wqe->words[13];
bde->addrLow = first_data_sgl->addr_lo;
@@ -3390,12 +3391,15 @@ lpfc_scsi_prep_dma_buf_s4(struct lpfc_hb
bde->tus.f.bdeFlags = BUFF_TYPE_BDE_64;
bde->tus.w = cpu_to_le32(bde->tus.w);
+ /* Word 11 - set PBDE bit */
+ bf_set(wqe_pbde, &wqe->generic.wqe_com, 1);
} else {
memset(&wqe->words[13], 0, (sizeof(uint32_t) * 3));
+ /* Word 11 - PBDE bit disabled by default template */
}
} else {
sgl += 1;
- /* clear the last flag in the fcp_rsp map entry */
+ /* set the last flag in the fcp_rsp map entry */
sgl->word2 = le32_to_cpu(sgl->word2);
bf_set(lpfc_sli4_sge_last, sgl, 1);
sgl->word2 = cpu_to_le32(sgl->word2);
@@ -3408,10 +3412,6 @@ lpfc_scsi_prep_dma_buf_s4(struct lpfc_hb
}
}
- /* Word 11 */
- if (phba->cfg_enable_pbde)
- bf_set(wqe_pbde, &wqe->generic.wqe_com, 1);
-
/*
* Finish initializing those IOCB fields that are dependent on the
* scsi_cmnd request_buffer. Note that for SLI-2 the bdeSize is