[PATCH v5 1/2] scsi: ufs: Introduce hba performance monitor sysfs nodes

From: Can Guo
Date: Wed Apr 21 2021 - 22:29:23 EST


Add a new sysfs group which has nodes to monitor data/request transfer
performance. This sysfs group has nodes showing total sectors/requests
transferred, total busy time spent and max/min/avg/sum latencies. This
group can be enhanced later to show more UFS driver layer performance
statistics data during runtime.

Signed-off-by: Can Guo <cang@xxxxxxxxxxxxxx>
---
drivers/scsi/ufs/ufs-sysfs.c | 237 +++++++++++++++++++++++++++++++++++++++++++
drivers/scsi/ufs/ufshcd.c | 62 +++++++++++
drivers/scsi/ufs/ufshcd.h | 21 ++++
3 files changed, 320 insertions(+)

diff --git a/drivers/scsi/ufs/ufs-sysfs.c b/drivers/scsi/ufs/ufs-sysfs.c
index acc54f5..348df0e 100644
--- a/drivers/scsi/ufs/ufs-sysfs.c
+++ b/drivers/scsi/ufs/ufs-sysfs.c
@@ -278,6 +278,242 @@ static const struct attribute_group ufs_sysfs_default_group = {
.attrs = ufs_sysfs_ufshcd_attrs,
};

+static ssize_t monitor_enable_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct ufs_hba *hba = dev_get_drvdata(dev);
+
+ return sysfs_emit(buf, "%d\n", hba->monitor.enabled);
+}
+
+static ssize_t monitor_enable_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct ufs_hba *hba = dev_get_drvdata(dev);
+ unsigned long value, flags;
+
+ if (kstrtoul(buf, 0, &value))
+ return -EINVAL;
+
+ value = !!value;
+ spin_lock_irqsave(hba->host->host_lock, flags);
+ if (value == hba->monitor.enabled)
+ goto out_unlock;
+
+ if (!value) {
+ memset(&hba->monitor, 0, sizeof(hba->monitor));
+ } else {
+ hba->monitor.enabled = true;
+ hba->monitor.enabled_ts = ktime_get();
+ }
+
+out_unlock:
+ spin_unlock_irqrestore(hba->host->host_lock, flags);
+ return count;
+}
+
+static ssize_t monitor_chunk_size_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct ufs_hba *hba = dev_get_drvdata(dev);
+
+ return sysfs_emit(buf, "%lu\n", hba->monitor.chunk_size);
+}
+
+static ssize_t monitor_chunk_size_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct ufs_hba *hba = dev_get_drvdata(dev);
+ unsigned long value, flags;
+
+ if (kstrtoul(buf, 0, &value))
+ return -EINVAL;
+
+ spin_lock_irqsave(hba->host->host_lock, flags);
+ /* Only allow chunk size change when monitor is disabled */
+ if (!hba->monitor.enabled)
+ hba->monitor.chunk_size = value;
+ spin_unlock_irqrestore(hba->host->host_lock, flags);
+ return count;
+}
+
+static ssize_t read_total_sectors_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct ufs_hba *hba = dev_get_drvdata(dev);
+
+ return sysfs_emit(buf, "%lu\n", hba->monitor.nr_sec_rw[READ]);
+}
+
+static ssize_t read_total_busy_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct ufs_hba *hba = dev_get_drvdata(dev);
+
+ return sysfs_emit(buf, "%llu\n",
+ ktime_to_us(hba->monitor.total_busy[READ]));
+}
+
+static ssize_t read_nr_requests_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct ufs_hba *hba = dev_get_drvdata(dev);
+
+ return sysfs_emit(buf, "%lu\n", hba->monitor.nr_req[READ]);
+}
+
+static ssize_t read_req_latency_avg_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct ufs_hba *hba = dev_get_drvdata(dev);
+ struct ufs_hba_monitor *m = &hba->monitor;
+
+ return sysfs_emit(buf, "%llu\n", div_u64(ktime_to_us(m->lat_sum[READ]),
+ m->nr_req[READ]));
+}
+
+static ssize_t read_req_latency_max_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct ufs_hba *hba = dev_get_drvdata(dev);
+
+ return sysfs_emit(buf, "%llu\n",
+ ktime_to_us(hba->monitor.lat_max[READ]));
+}
+
+static ssize_t read_req_latency_min_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct ufs_hba *hba = dev_get_drvdata(dev);
+
+ return sysfs_emit(buf, "%llu\n",
+ ktime_to_us(hba->monitor.lat_min[READ]));
+}
+
+static ssize_t read_req_latency_sum_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct ufs_hba *hba = dev_get_drvdata(dev);
+
+ return sysfs_emit(buf, "%llu\n",
+ ktime_to_us(hba->monitor.lat_sum[READ]));
+}
+
+static ssize_t write_total_sectors_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct ufs_hba *hba = dev_get_drvdata(dev);
+
+ return sysfs_emit(buf, "%lu\n", hba->monitor.nr_sec_rw[WRITE]);
+}
+
+static ssize_t write_total_busy_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct ufs_hba *hba = dev_get_drvdata(dev);
+
+ return sysfs_emit(buf, "%llu\n",
+ ktime_to_us(hba->monitor.total_busy[WRITE]));
+}
+
+static ssize_t write_nr_requests_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct ufs_hba *hba = dev_get_drvdata(dev);
+
+ return sysfs_emit(buf, "%lu\n", hba->monitor.nr_req[WRITE]);
+}
+
+static ssize_t write_req_latency_avg_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct ufs_hba *hba = dev_get_drvdata(dev);
+ struct ufs_hba_monitor *m = &hba->monitor;
+
+ return sysfs_emit(buf, "%llu\n", div_u64(ktime_to_us(m->lat_sum[WRITE]),
+ m->nr_req[WRITE]));
+}
+
+static ssize_t write_req_latency_max_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct ufs_hba *hba = dev_get_drvdata(dev);
+
+ return sysfs_emit(buf, "%llu\n",
+ ktime_to_us(hba->monitor.lat_max[WRITE]));
+}
+
+static ssize_t write_req_latency_min_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct ufs_hba *hba = dev_get_drvdata(dev);
+
+ return sysfs_emit(buf, "%llu\n",
+ ktime_to_us(hba->monitor.lat_min[WRITE]));
+}
+
+static ssize_t write_req_latency_sum_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct ufs_hba *hba = dev_get_drvdata(dev);
+
+ return sysfs_emit(buf, "%llu\n",
+ ktime_to_us(hba->monitor.lat_sum[WRITE]));
+}
+
+static DEVICE_ATTR_RW(monitor_enable);
+static DEVICE_ATTR_RW(monitor_chunk_size);
+static DEVICE_ATTR_RO(read_total_sectors);
+static DEVICE_ATTR_RO(read_total_busy);
+static DEVICE_ATTR_RO(read_nr_requests);
+static DEVICE_ATTR_RO(read_req_latency_avg);
+static DEVICE_ATTR_RO(read_req_latency_max);
+static DEVICE_ATTR_RO(read_req_latency_min);
+static DEVICE_ATTR_RO(read_req_latency_sum);
+static DEVICE_ATTR_RO(write_total_sectors);
+static DEVICE_ATTR_RO(write_total_busy);
+static DEVICE_ATTR_RO(write_nr_requests);
+static DEVICE_ATTR_RO(write_req_latency_avg);
+static DEVICE_ATTR_RO(write_req_latency_max);
+static DEVICE_ATTR_RO(write_req_latency_min);
+static DEVICE_ATTR_RO(write_req_latency_sum);
+
+static struct attribute *ufs_sysfs_monitor_attrs[] = {
+ &dev_attr_monitor_enable.attr,
+ &dev_attr_monitor_chunk_size.attr,
+ &dev_attr_read_total_sectors.attr,
+ &dev_attr_read_total_busy.attr,
+ &dev_attr_read_nr_requests.attr,
+ &dev_attr_read_req_latency_avg.attr,
+ &dev_attr_read_req_latency_max.attr,
+ &dev_attr_read_req_latency_min.attr,
+ &dev_attr_read_req_latency_sum.attr,
+ &dev_attr_write_total_sectors.attr,
+ &dev_attr_write_total_busy.attr,
+ &dev_attr_write_nr_requests.attr,
+ &dev_attr_write_req_latency_avg.attr,
+ &dev_attr_write_req_latency_max.attr,
+ &dev_attr_write_req_latency_min.attr,
+ &dev_attr_write_req_latency_sum.attr,
+ NULL
+};
+
+static const struct attribute_group ufs_sysfs_monitor_group = {
+ .name = "monitor",
+ .attrs = ufs_sysfs_monitor_attrs,
+};
+
static ssize_t ufs_sysfs_read_desc_param(struct ufs_hba *hba,
enum desc_idn desc_id,
u8 desc_index,
@@ -881,6 +1117,7 @@ static const struct attribute_group ufs_sysfs_attributes_group = {

static const struct attribute_group *ufs_sysfs_groups[] = {
&ufs_sysfs_default_group,
+ &ufs_sysfs_monitor_group,
&ufs_sysfs_device_descriptor_group,
&ufs_sysfs_interconnect_descriptor_group,
&ufs_sysfs_geometry_descriptor_group,
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 80620c8..6da1da8 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -2028,6 +2028,64 @@ static void ufshcd_clk_scaling_update_busy(struct ufs_hba *hba)
scaling->is_busy_started = false;
}
}
+
+static inline int ufshcd_monitor_opcode2dir(u8 opcode)
+{
+ if (opcode == READ_6 || opcode == READ_10 || opcode == READ_16)
+ return READ;
+ else if (opcode == WRITE_6 || opcode == WRITE_10 || opcode == WRITE_16)
+ return WRITE;
+ else
+ return -EINVAL;
+}
+
+static inline bool ufshcd_should_inform_monitor(struct ufs_hba *hba,
+ struct ufshcd_lrb *lrbp)
+{
+ struct ufs_hba_monitor *m = &hba->monitor;
+
+ return (m->enabled && lrbp && lrbp->cmd &&
+ (!m->chunk_size || m->chunk_size == lrbp->cmd->sdb.length) &&
+ ktime_before(hba->monitor.enabled_ts, lrbp->issue_time_stamp));
+}
+
+static void ufshcd_start_monitor(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
+{
+ int dir = ufshcd_monitor_opcode2dir(*lrbp->cmd->cmnd);
+
+ if (dir >= 0 && hba->monitor.nr_queued[dir]++ == 0)
+ hba->monitor.busy_start_ts[dir] = ktime_get();
+}
+
+static void ufshcd_update_monitor(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
+{
+ int dir = ufshcd_monitor_opcode2dir(*lrbp->cmd->cmnd);
+
+ if (dir >= 0 && hba->monitor.nr_queued[dir] > 0) {
+ struct request *req = lrbp->cmd->request;
+ struct ufs_hba_monitor *m = &hba->monitor;
+ ktime_t now, inc, lat;
+
+ now = lrbp->compl_time_stamp;
+ inc = ktime_sub(now, m->busy_start_ts[dir]);
+ m->total_busy[dir] = ktime_add(m->total_busy[dir], inc);
+ m->nr_sec_rw[dir] += blk_rq_sectors(req);
+
+ /* Update latencies */
+ m->nr_req[dir]++;
+ lat = ktime_sub(now, lrbp->issue_time_stamp);
+ m->lat_sum[dir] += lat;
+ if (m->lat_max[dir] < lat || !m->lat_max[dir])
+ m->lat_max[dir] = lat;
+ if (m->lat_min[dir] > lat || !m->lat_min[dir])
+ m->lat_min[dir] = lat;
+
+ m->nr_queued[dir]--;
+ /* Push forward the busy start of monitor */
+ m->busy_start_ts[dir] = now;
+ }
+}
+
/**
* ufshcd_send_command - Send SCSI or device management commands
* @hba: per adapter instance
@@ -2044,6 +2102,8 @@ void ufshcd_send_command(struct ufs_hba *hba, unsigned int task_tag)
ufshcd_add_command_trace(hba, task_tag, UFS_CMD_SEND);
ufshcd_clk_scaling_start_busy(hba);
__set_bit(task_tag, &hba->outstanding_reqs);
+ if (unlikely(ufshcd_should_inform_monitor(hba, lrbp)))
+ ufshcd_start_monitor(hba, lrbp);
ufshcd_writel(hba, 1 << task_tag, REG_UTP_TRANSFER_REQ_DOOR_BELL);
/* Make sure that doorbell is committed immediately */
wmb();
@@ -5098,6 +5158,8 @@ static void __ufshcd_transfer_req_compl(struct ufs_hba *hba,
lrbp->compl_time_stamp = ktime_get();
cmd = lrbp->cmd;
if (cmd) {
+ if (unlikely(ufshcd_should_inform_monitor(hba, lrbp)))
+ ufshcd_update_monitor(hba, lrbp);
ufshcd_add_command_trace(hba, index, UFS_CMD_COMP);
result = ufshcd_transfer_rsp_status(hba, lrbp);
scsi_dma_unmap(cmd);
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 18e56c1..2bfe20e 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -645,6 +645,25 @@ struct ufs_hba_variant_params {
u32 wb_flush_threshold;
};

+struct ufs_hba_monitor {
+ unsigned long chunk_size;
+
+ unsigned long nr_sec_rw[2];
+ ktime_t total_busy[2];
+
+ unsigned long nr_req[2];
+ /* latencies*/
+ ktime_t lat_sum[2];
+ ktime_t lat_max[2];
+ ktime_t lat_min[2];
+
+ u32 nr_queued[2];
+ ktime_t busy_start_ts[2];
+
+ ktime_t enabled_ts;
+ bool enabled;
+};
+
/**
* struct ufs_hba - per adapter private structure
* @mmio_base: UFSHCI base register address
@@ -832,6 +851,8 @@ struct ufs_hba {
struct request_queue *bsg_queue;
struct delayed_work rpm_dev_flush_recheck_work;

+ struct ufs_hba_monitor monitor;
+
#ifdef CONFIG_SCSI_UFS_CRYPTO
union ufs_crypto_capabilities crypto_capabilities;
union ufs_crypto_cap_entry *crypto_cap_array;
--
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