[PATCH 3/7] smartpqi: add counter for parity write stream requests

Don Brace
2024-08-27T18:55:30Z

From: Mahesh Rajashekhara <mahesh.rajashekhara@microchip.com>

Add sysfs entry to check for write stream requests.

Move existing raid_bypass_cnt into a structure named
pqi_raid_io_stats and add member write_stream_cnt. These two counters
are related because write stream detection is only checked if an I/O
request is eligible for bypass (AIO).

Example usage:

lsscsi
[15:1:0:0] disk Adaptec LOGICAL VOLUME 0129 /dev/sdae

cat /sys/block/sdae/device/ssd_smart_path_enabled
1
^
|
+---- NOTE: here bypass has been enabled on device sdae

To read the counter for parity write stream requests:

cat /sys/block/sdae/device/write_stream_cnt
0x60cd507

Reviewed-by: Scott Benesh <scott.benesh@microchip.com>
Reviewed-by: Mike McGowen <mike.mcgowen@microchip.com>
Signed-off-by: Mahesh Rajashekhara <mahesh.rajashekhara@microchip.com>
Co-developed-by: Kevin Barnett <kevin.barnett@microchip.com>
Signed-off-by: Kevin Barnett <kevin.barnett@microchip.com>
Signed-off-by: Don Brace <don.brace@microchip.com>
---
drivers/scsi/smartpqi/smartpqi.h | 7 ++-
drivers/scsi/smartpqi/smartpqi_init.c | 62 +++++++++++++++++++++------
2 files changed, 55 insertions(+), 14 deletions(-)

diff --git a/drivers/scsi/smartpqi/smartpqi.h b/drivers/scsi/smartpqi/smartpqi.h
index f493006bee9d..fae6db20a6e9 100644
--- a/drivers/scsi/smartpqi/smartpqi.h
+++ b/drivers/scsi/smartpqi/smartpqi.h
@@ -1106,6 +1106,11 @@ struct pqi_tmf_work {
u8 scsi_opcode;
};

+struct pqi_raid_io_stats {
+ u64 raid_bypass_cnt;
+ u64 write_stream_cnt;
+};
+
struct pqi_scsi_dev {
int devtype; /* as reported by INQUIRY command */
u8 device_type; /* as reported by */
@@ -1168,7 +1173,7 @@ struct pqi_scsi_dev {

struct pqi_stream_data stream_data[NUM_STREAMS_PER_LUN];
atomic_t scsi_cmds_outstanding[PQI_MAX_LUNS_PER_DEVICE];
- u64 __percpu *raid_bypass_cnt;
+ struct pqi_raid_io_stats __percpu *raid_io_stats;

struct pqi_tmf_work tmf_work[PQI_MAX_LUNS_PER_DEVICE];
};
diff --git a/drivers/scsi/smartpqi/smartpqi_init.c b/drivers/scsi/smartpqi/smartpqi_init.c
index 8e2e71ab49ae..6a941735c982 100644
--- a/drivers/scsi/smartpqi/smartpqi_init.c
+++ b/drivers/scsi/smartpqi/smartpqi_init.c
@@ -1508,8 +1508,8 @@ static int pqi_get_raid_map(struct pqi_ctrl_info *ctrl_info,
if (rc)
goto error;

- device->raid_bypass_cnt = alloc_percpu(u64);
- if (!device->raid_bypass_cnt) {
+ device->raid_io_stats = alloc_percpu(struct pqi_raid_io_stats);
+ if (!device->raid_io_stats) {
rc = -ENOMEM;
goto error;
}
@@ -2105,9 +2105,9 @@ static void pqi_scsi_update_device(struct pqi_ctrl_info *ctrl_info,
/* To prevent this from being freed later. */
new_device->raid_map = NULL;
}
- if (new_device->raid_bypass_enabled && existing_device->raid_bypass_cnt == NULL) {
- existing_device->raid_bypass_cnt = new_device->raid_bypass_cnt;
- new_device->raid_bypass_cnt = NULL;
+ if (new_device->raid_bypass_enabled && existing_device->raid_io_stats == NULL) {
+ existing_device->raid_io_stats = new_device->raid_io_stats;
+ new_device->raid_io_stats = NULL;
}
existing_device->raid_bypass_configured = new_device->raid_bypass_configured;
existing_device->raid_bypass_enabled = new_device->raid_bypass_enabled;
@@ -2131,7 +2131,7 @@ static void pqi_scsi_update_device(struct pqi_ctrl_info *ctrl_info,
static inline void pqi_free_device(struct pqi_scsi_dev *device)
{
if (device) {
- free_percpu(device->raid_bypass_cnt);
+ free_percpu(device->raid_io_stats);
kfree(device->raid_map);
kfree(device);
}
@@ -5984,6 +5984,7 @@ static bool pqi_is_parity_write_stream(struct pqi_ctrl_info *ctrl_info,
pqi_stream_data->next_lba = rmd.first_block +
rmd.block_cnt;
pqi_stream_data->last_accessed = jiffies;
+ per_cpu_ptr(device->raid_io_stats, smp_processor_id())->write_stream_cnt++;
return true;
}

@@ -6016,7 +6017,6 @@ static int pqi_scsi_queue_command(struct Scsi_Host *shost, struct scsi_cmnd *scm
u16 hw_queue;
struct pqi_queue_group *queue_group;
bool raid_bypassed;
- u64 *raid_bypass_cnt;
u8 lun;

scmd->host_scribble = PQI_NO_COMPLETION;
@@ -6063,8 +6063,7 @@ 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;
- raid_bypass_cnt = per_cpu_ptr(device->raid_bypass_cnt, smp_processor_id());
- (*raid_bypass_cnt)++;
+ per_cpu_ptr(device->raid_io_stats, smp_processor_id())->raid_bypass_cnt++;
}
}
if (!raid_bypassed)
@@ -7363,7 +7362,6 @@ static ssize_t pqi_raid_bypass_cnt_show(struct device *dev,
unsigned long flags;
u64 raid_bypass_cnt;
int cpu;
- u64 *per_cpu_bypass_cnt_ptr;

sdev = to_scsi_device(dev);
ctrl_info = shost_to_hba(sdev->host);
@@ -7381,10 +7379,9 @@ static ssize_t pqi_raid_bypass_cnt_show(struct device *dev,

raid_bypass_cnt = 0;

- if (device->raid_bypass_cnt) {
+ if (device->raid_io_stats) {
for_each_online_cpu(cpu) {
- per_cpu_bypass_cnt_ptr = per_cpu_ptr(device->raid_bypass_cnt, cpu);
- raid_bypass_cnt += *per_cpu_bypass_cnt_ptr;
+ raid_bypass_cnt += per_cpu_ptr(device->raid_io_stats, cpu)->raid_bypass_cnt;
}
}

@@ -7472,6 +7469,43 @@ static ssize_t pqi_numa_node_show(struct device *dev,
return scnprintf(buffer, PAGE_SIZE, "%d\n", ctrl_info->numa_node);
}

+static ssize_t pqi_write_stream_cnt_show(struct device *dev,
+ struct device_attribute *attr, char *buffer)
+{
+ struct pqi_ctrl_info *ctrl_info;
+ struct scsi_device *sdev;
+ struct pqi_scsi_dev *device;
+ unsigned long flags;
+ u64 write_stream_cnt;
+ int cpu;
+
+ sdev = to_scsi_device(dev);
+ ctrl_info = shost_to_hba(sdev->host);
+
+ if (pqi_ctrl_offline(ctrl_info))
+ return -ENODEV;
+
+ spin_lock_irqsave(&ctrl_info->scsi_device_list_lock, flags);
+
+ device = sdev->hostdata;
+ if (!device) {
+ spin_unlock_irqrestore(&ctrl_info->scsi_device_list_lock, flags);
+ return -ENODEV;
+ }
+
+ write_stream_cnt = 0;
+
+ if (device->raid_io_stats) {
+ for_each_online_cpu(cpu) {
+ write_stream_cnt += per_cpu_ptr(device->raid_io_stats, cpu)->write_stream_cnt;
+ }
+ }
+
+ spin_unlock_irqrestore(&ctrl_info->scsi_device_list_lock, flags);
+
+ return scnprintf(buffer, PAGE_SIZE, "0x%llx\n", write_stream_cnt);
+}
+
static DEVICE_ATTR(lunid, 0444, pqi_lunid_show, NULL);
static DEVICE_ATTR(unique_id, 0444, pqi_unique_id_show, NULL);
static DEVICE_ATTR(path_info, 0444, pqi_path_info_show, NULL);
@@ -7482,6 +7516,7 @@ static DEVICE_ATTR(raid_bypass_cnt, 0444, pqi_raid_bypass_cnt_show, NULL);
static DEVICE_ATTR(sas_ncq_prio_enable, 0644,
pqi_sas_ncq_prio_enable_show, pqi_sas_ncq_prio_enable_store);
static DEVICE_ATTR(numa_node, 0444, pqi_numa_node_show, NULL);
+static DEVICE_ATTR(write_stream_cnt, 0444, pqi_write_stream_cnt_show, NULL);

static struct attribute *pqi_sdev_attrs[] = {
&dev_attr_lunid.attr,
@@ -7493,6 +7528,7 @@ static struct attribute *pqi_sdev_attrs[] = {
&dev_attr_raid_bypass_cnt.attr,
&dev_attr_sas_ncq_prio_enable.attr,
&dev_attr_numa_node.attr,
+ &dev_attr_write_stream_cnt.attr,
NULL
};

--
2.46.0.421.g159f2d50e7