diff options
| author | John Garry <john.garry@huawei.com> | 2016-09-06 15:36:11 (GMT) |
|---|---|---|
| committer | Martin K. Petersen <martin.petersen@oracle.com> | 2016-09-14 16:54:17 (GMT) |
| commit | e6c346f303d41b8799ea224d0faf1b2caa1c98db (patch) | |
| tree | 5ab81caef92f48c4960acefc2e66605b2e05eab4 /drivers/scsi/hisi_sas/hisi_sas_v1_hw.c | |
| parent | c4a11827b760ef8dcda26b5731d072b1d8fb7c81 (diff) | |
| download | linux-e6c346f303d41b8799ea224d0faf1b2caa1c98db.tar.xz | |
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 <john.garry@huawei.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'drivers/scsi/hisi_sas/hisi_sas_v1_hw.c')
| -rw-r--r-- | drivers/scsi/hisi_sas/hisi_sas_v1_hw.c | 6 |
1 files changed, 2 insertions, 4 deletions
diff --git a/drivers/scsi/hisi_sas/hisi_sas_v1_hw.c b/drivers/scsi/hisi_sas/hisi_sas_v1_hw.c index 1abbc2e..3b31b20 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; |