From 4fde02ad66dc9ceb0b55daca21ef33b43df30ded Mon Sep 17 00:00:00 2001
From: John Garry <john.garry@huawei.com>
Date: Tue, 6 Sep 2016 23:36:12 +0800
Subject: [PATCH] scsi: hisi_sas: save delivery queue write pointer
Optimise by saving an avoidable read in the get_free_slot function. The
delivery queue write pointer will only be updated by software, so don't
bother re-reading what was already written in the previous call to
start_delivery function.
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
---
drivers/scsi/hisi_sas/hisi_sas.h | 7 +++++++
drivers/scsi/hisi_sas/hisi_sas_main.c | 5 +++++
drivers/scsi/hisi_sas/hisi_sas_v1_hw.c | 12 +++++++-----
drivers/scsi/hisi_sas/hisi_sas_v2_hw.c | 9 ++++++---
4 files changed, 25 insertions(+), 8 deletions(-)
diff --git a/drivers/scsi/hisi_sas/hisi_sas.h b/drivers/scsi/hisi_sas/hisi_sas.h
index 9410335caf41..72c98522bd26 100644
--- a/drivers/scsi/hisi_sas/hisi_sas.h
+++ b/drivers/scsi/hisi_sas/hisi_sas.h
@@ -98,6 +98,12 @@ struct hisi_sas_cq {
int id;
};
+struct hisi_sas_dq {
+ struct hisi_hba *hisi_hba;
+ int wr_point;
+ int id;
+};
+
struct hisi_sas_device {
enum sas_device_type dev_type;
struct hisi_hba *hisi_hba;
@@ -194,6 +200,7 @@ struct hisi_hba {
struct Scsi_Host *shost;
struct hisi_sas_cq cq[HISI_SAS_MAX_QUEUES];
+ struct hisi_sas_dq dq[HISI_SAS_MAX_QUEUES];
struct hisi_sas_phy phy[HISI_SAS_MAX_PHYS];
struct hisi_sas_port port[HISI_SAS_MAX_PHYS];
diff --git a/drivers/scsi/hisi_sas/hisi_sas_main.c b/drivers/scsi/hisi_sas/hisi_sas_main.c
index 85c73d311e4d..5d5657670d4c 100644
--- a/drivers/scsi/hisi_sas/hisi_sas_main.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_main.c
@@ -1239,11 +1239,16 @@ static int hisi_sas_alloc(struct hisi_hba *hisi_hba, struct Scsi_Host *shost)
for (i = 0; i < hisi_hba->queue_count; i++) {
struct hisi_sas_cq *cq = &hisi_hba->cq[i];
+ struct hisi_sas_dq *dq = &hisi_hba->dq[i];
/* Completion queue structure */
cq->id = i;
cq->hisi_hba = hisi_hba;
+ /* Delivery queue structure */
+ dq->id = i;
+ dq->hisi_hba = hisi_hba;
+
/* Delivery queue */
s = sizeof(struct hisi_sas_cmd_hdr) * HISI_SAS_QUEUE_SLOTS;
hisi_hba->cmd_hdr[i] = dma_alloc_coherent(dev, s,
diff --git a/drivers/scsi/hisi_sas/hisi_sas_v1_hw.c b/drivers/scsi/hisi_sas/hisi_sas_v1_hw.c
index 3b31b2046559..b5374641bdb0 100644
--- a/drivers/scsi/hisi_sas/hisi_sas_v1_hw.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_v1_hw.c
@@ -875,12 +875,13 @@ static int get_wideport_bitmap_v1_hw(struct hisi_hba *hisi_hba, int port_id)
static int get_free_slot_v1_hw(struct hisi_hba *hisi_hba, int *q, int *s)
{
struct device *dev = &hisi_hba->pdev->dev;
+ struct hisi_sas_dq *dq;
u32 r, w;
int queue = hisi_hba->queue;
while (1) {
- w = hisi_sas_read32_relaxed(hisi_hba,
- DLVRY_Q_0_WR_PTR + (queue * 0x14));
+ dq = &hisi_hba->dq[queue];
+ w = dq->wr_point;
r = hisi_sas_read32_relaxed(hisi_hba,
DLVRY_Q_0_RD_PTR + (queue * 0x14));
if (r == (w+1) % HISI_SAS_QUEUE_SLOTS) {
@@ -903,10 +904,11 @@ static void start_delivery_v1_hw(struct hisi_hba *hisi_hba)
{
int dlvry_queue = hisi_hba->slot_prep->dlvry_queue;
int dlvry_queue_slot = hisi_hba->slot_prep->dlvry_queue_slot;
+ struct hisi_sas_dq *dq = &hisi_hba->dq[dlvry_queue];
- hisi_sas_write32(hisi_hba,
- DLVRY_Q_0_WR_PTR + (dlvry_queue * 0x14),
- ++dlvry_queue_slot % HISI_SAS_QUEUE_SLOTS);
+ dq->wr_point = ++dlvry_queue_slot % HISI_SAS_QUEUE_SLOTS;
+ hisi_sas_write32(hisi_hba, DLVRY_Q_0_WR_PTR + (dlvry_queue * 0x14),
+ dq->wr_point);
}
static int prep_prd_sge_v1_hw(struct hisi_hba *hisi_hba,
diff --git a/drivers/scsi/hisi_sas/hisi_sas_v2_hw.c b/drivers/scsi/hisi_sas/hisi_sas_v2_hw.c
index 11006c99de54..e0c124b6428e 100644
--- a/drivers/scsi/hisi_sas/hisi_sas_v2_hw.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_v2_hw.c
@@ -1023,12 +1023,13 @@ static int get_wideport_bitmap_v2_hw(struct hisi_hba *hisi_hba, int port_id)
static int get_free_slot_v2_hw(struct hisi_hba *hisi_hba, int *q, int *s)
{
struct device *dev = &hisi_hba->pdev->dev;
+ struct hisi_sas_dq *dq;
u32 r, w;
int queue = hisi_hba->queue;
while (1) {
- w = hisi_sas_read32_relaxed(hisi_hba,
- DLVRY_Q_0_WR_PTR + (queue * 0x14));
+ dq = &hisi_hba->dq[queue];
+ w = dq->wr_point;
r = hisi_sas_read32_relaxed(hisi_hba,
DLVRY_Q_0_RD_PTR + (queue * 0x14));
if (r == (w+1) % HISI_SAS_QUEUE_SLOTS) {
@@ -1051,9 +1052,11 @@ static void start_delivery_v2_hw(struct hisi_hba *hisi_hba)
{
int dlvry_queue = hisi_hba->slot_prep->dlvry_queue;
int dlvry_queue_slot = hisi_hba->slot_prep->dlvry_queue_slot;
+ struct hisi_sas_dq *dq = &hisi_hba->dq[dlvry_queue];
+ dq->wr_point = ++dlvry_queue_slot % HISI_SAS_QUEUE_SLOTS;
hisi_sas_write32(hisi_hba, DLVRY_Q_0_WR_PTR + (dlvry_queue * 0x14),
- ++dlvry_queue_slot % HISI_SAS_QUEUE_SLOTS);
+ dq->wr_point);
}
static int prep_prd_sge_v2_hw(struct hisi_hba *hisi_hba,