scsi: megaraid_sas: Expose fw_cmds_outstanding through sysfs

Expose FW outstanding commands (fw_outstanding) through sysfs interface.
This helps in debugging certain performance issues in the field.
Signed-off-by: Sasikumar Chandrasekaran <sasikumar.pc@broadcom.com>
Signed-off-by: Shivasharan S <shivasharan.srikanteshwara@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/megaraid/megaraid_sas_base.c

@@ -3122,6 +3122,16 @@ megasas_ldio_outstanding_show(struct device *cdev, struct device_attribute *attr
 	return snprintf(buf, PAGE_SIZE, "%d\n", atomic_read(&instance->ldio_outstanding));
 }
 
+static ssize_t
+megasas_fw_cmds_outstanding_show(struct device *cdev,
+				 struct device_attribute *attr, char *buf)
+{
+	struct Scsi_Host *shost = class_to_shost(cdev);
+	struct megasas_instance *instance = (struct megasas_instance *)shost->hostdata;
+
+	return snprintf(buf, PAGE_SIZE, "%d\n", atomic_read(&instance->fw_outstanding));
+}
+
 static DEVICE_ATTR(fw_crash_buffer, S_IRUGO | S_IWUSR,
 	megasas_fw_crash_buffer_show, megasas_fw_crash_buffer_store);
 static DEVICE_ATTR(fw_crash_buffer_size, S_IRUGO,
@@ -3132,6 +3142,8 @@ static DEVICE_ATTR(page_size, S_IRUGO,
 	megasas_page_size_show, NULL);
 static DEVICE_ATTR(ldio_outstanding, S_IRUGO,
 	megasas_ldio_outstanding_show, NULL);
+static DEVICE_ATTR(fw_cmds_outstanding, S_IRUGO,
+	megasas_fw_cmds_outstanding_show, NULL);
 
 struct device_attribute *megaraid_host_attrs[] = {
 	&dev_attr_fw_crash_buffer_size,
@@ -3139,6 +3151,7 @@ struct device_attribute *megaraid_host_attrs[] = {
 	&dev_attr_fw_crash_state,
 	&dev_attr_page_size,
 	&dev_attr_ldio_outstanding,
+	&dev_attr_fw_cmds_outstanding,
 	NULL,
 };