From: Mike McGowen <mike.mcgowen@xxxxxxxxxxxxx>
Reduce CPU contention when incrementing variable raid_bypass_cnt.
Remove the atomic operations for this variable by changing
the atomic to an unsigned int and replace atomic operations with
standard operations. The value is only checked that it is increasing
and accuracy is not required.
Reviewed-by: Scott Benesh <scott.benesh@xxxxxxxxxxxxx>
Reviewed-by: Scott Teel <scott.teel@xxxxxxxxxxxxx>
Reviewed-by: Kevin Barnett <kevin.barnett@xxxxxxxxxxxxx>
Signed-off-by: Mike McGowen <mike.mcgowen@xxxxxxxxxxxxx>
Signed-off-by: Don Brace <don.brace@xxxxxxxxxxxxx>
---
drivers/scsi/smartpqi/smartpqi.h | 2 +-
drivers/scsi/smartpqi/smartpqi_init.c | 6 +++---
2 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/scsi/smartpqi/smartpqi.h b/drivers/scsi/smartpqi/smartpqi.h
index 228838eb3686..659a087a0e52 100644
--- a/drivers/scsi/smartpqi/smartpqi.h
+++ b/drivers/scsi/smartpqi/smartpqi.h
@@ -1147,7 +1147,7 @@ struct pqi_scsi_dev {
struct pqi_stream_data stream_data[NUM_STREAMS_PER_LUN];
atomic_t scsi_cmds_outstanding[PQI_MAX_LUNS_PER_DEVICE];
- atomic_t raid_bypass_cnt;
+ unsigned int raid_bypass_cnt;
};
/* VPD inquiry pages */
diff --git a/drivers/scsi/smartpqi/smartpqi_init.c b/drivers/scsi/smartpqi/smartpqi_init.c
index 3daad878bafa..7fe80bef1a15 100644
--- a/drivers/scsi/smartpqi/smartpqi_init.c
+++ b/drivers/scsi/smartpqi/smartpqi_init.c
@@ -6052,7 +6052,7 @@ static int pqi_scsi_queue_command(struct Scsi_Host *shost, struct scsi_cmnd *scm
rc = pqi_raid_bypass_submit_scsi_cmd(ctrl_info, device, scmd, queue_group);
if (rc == 0 || rc == SCSI_MLQUEUE_HOST_BUSY) {
raid_bypassed = true;
- atomic_inc(&device->raid_bypass_cnt);
+ device->raid_bypass_cnt++;
}
}
if (!raid_bypassed)
@@ -7288,7 +7288,7 @@ static ssize_t pqi_raid_bypass_cnt_show(struct device *dev,
struct scsi_device *sdev;
struct pqi_scsi_dev *device;
unsigned long flags;
- int raid_bypass_cnt;
+ unsigned int raid_bypass_cnt;
sdev = to_scsi_device(dev);
ctrl_info = shost_to_hba(sdev->host);
@@ -7304,7 +7304,7 @@ static ssize_t pqi_raid_bypass_cnt_show(struct device *dev,
return -ENODEV;
}
- raid_bypass_cnt = atomic_read(&device->raid_bypass_cnt);
+ raid_bypass_cnt = device->raid_bypass_cnt;
spin_unlock_irqrestore(&ctrl_info->scsi_device_list_lock, flags);
--
2.40.1.375.g9ce9dea4e1
