From e6c346f303d41b8799ea224d0faf1b2caa1c98db Mon Sep 17 00:00:00 2001 From: John Garry Date: Tue, 6 Sep 2016 23:36:11 +0800 Subject: scsi: hisi_sas: save completion queue read pointer Optimise by saving an avoidable read in the cq interrupt. The queue read pointer will only be updated by software, so don't bother re-reading what was already written in the previous interrupt. Signed-off-by: John Garry Reviewed-by: Hannes Reinecke Signed-off-by: Martin K. Petersen --- drivers/scsi/hisi_sas/hisi_sas.h | 1 + drivers/scsi/hisi_sas/hisi_sas_v1_hw.c | 6 ++---- drivers/scsi/hisi_sas/hisi_sas_v2_hw.c | 5 ++--- 3 files changed, 5 insertions(+), 7 deletions(-) (limited to 'drivers/scsi') diff --git a/drivers/scsi/hisi_sas/hisi_sas.h b/drivers/scsi/hisi_sas/hisi_sas.h index ca55ec2974e0..9410335caf41 100644 --- a/drivers/scsi/hisi_sas/hisi_sas.h +++ b/drivers/scsi/hisi_sas/hisi_sas.h @@ -94,6 +94,7 @@ struct hisi_sas_port { struct hisi_sas_cq { struct hisi_hba *hisi_hba; + int rd_point; int id; }; diff --git a/drivers/scsi/hisi_sas/hisi_sas_v1_hw.c b/drivers/scsi/hisi_sas/hisi_sas_v1_hw.c index 1abbc2e162df..3b31b2046559 100644 --- a/drivers/scsi/hisi_sas/hisi_sas_v1_hw.c +++ b/drivers/scsi/hisi_sas/hisi_sas_v1_hw.c @@ -1565,14 +1565,11 @@ static irqreturn_t cq_interrupt_v1_hw(int irq, void *p) struct hisi_sas_complete_v1_hdr *complete_queue = (struct hisi_sas_complete_v1_hdr *) hisi_hba->complete_hdr[queue]; - u32 irq_value, rd_point, wr_point; + u32 irq_value, rd_point = cq->rd_point, wr_point; irq_value = hisi_sas_read32(hisi_hba, OQ_INT_SRC); hisi_sas_write32(hisi_hba, OQ_INT_SRC, 1 << queue); - - rd_point = hisi_sas_read32(hisi_hba, - COMPL_Q_0_RD_PTR + (0x14 * queue)); wr_point = hisi_sas_read32(hisi_hba, COMPL_Q_0_WR_PTR + (0x14 * queue)); @@ -1600,6 +1597,7 @@ static irqreturn_t cq_interrupt_v1_hw(int irq, void *p) } /* update rd_point */ + cq->rd_point = rd_point; hisi_sas_write32(hisi_hba, COMPL_Q_0_RD_PTR + (0x14 * queue), rd_point); return IRQ_HANDLED; diff --git a/drivers/scsi/hisi_sas/hisi_sas_v2_hw.c b/drivers/scsi/hisi_sas/hisi_sas_v2_hw.c index bf9b693a717f..11006c99de54 100644 --- a/drivers/scsi/hisi_sas/hisi_sas_v2_hw.c +++ b/drivers/scsi/hisi_sas/hisi_sas_v2_hw.c @@ -2049,7 +2049,7 @@ static irqreturn_t cq_interrupt_v2_hw(int irq_no, void *p) struct hisi_sas_slot *slot; struct hisi_sas_itct *itct; struct hisi_sas_complete_v2_hdr *complete_queue; - u32 irq_value, rd_point, wr_point, dev_id; + u32 irq_value, rd_point = cq->rd_point, wr_point, dev_id; int queue = cq->id; complete_queue = hisi_hba->complete_hdr[queue]; @@ -2057,8 +2057,6 @@ static irqreturn_t cq_interrupt_v2_hw(int irq_no, void *p) hisi_sas_write32(hisi_hba, OQ_INT_SRC, 1 << queue); - rd_point = hisi_sas_read32(hisi_hba, COMPL_Q_0_RD_PTR + - (0x14 * queue)); wr_point = hisi_sas_read32(hisi_hba, COMPL_Q_0_WR_PTR + (0x14 * queue)); @@ -2106,6 +2104,7 @@ static irqreturn_t cq_interrupt_v2_hw(int irq_no, void *p) } /* update rd_point */ + cq->rd_point = rd_point; hisi_sas_write32(hisi_hba, COMPL_Q_0_RD_PTR + (0x14 * queue), rd_point); return IRQ_HANDLED; } -- cgit v1.2.3