[PATCH 3/3][RESUBMIT] scsi_dh_rdac: changes for rdac debug logging

Moger, Babu
2009-09-02T23:13:24Z

--- linux-2.6.31-rc5/drivers/scsi/device_handler/scsi_dh_rdac.c.orig 2009-08-31 15:16:54.000000000 -0500
+++ linux-2.6.31-rc5/drivers/scsi/device_handler/scsi_dh_rdac.c 2009-08-31 15:18:31.000000000 -0500
@@ -201,6 +201,31 @@ static const char *lun_state[] =
static LIST_HEAD(ctlr_list);
static DEFINE_SPINLOCK(list_lock);

+/*
+ * module parameter to enable rdac debug logging.
+ * 2 bits for each type of logging, only two types defined for now
+ * Can be enhanced if required at later point
+ */
+static int rdac_logging = 1;
+module_param(rdac_logging, int, S_IRUGO|S_IWUSR);
+MODULE_PARM_DESC(rdac_logging, "A bit mask of rdac logging levels, "
+ "Default is 1 - failover logging enabled, "
+ "set it to 0xF to enable all the logs");
+
+#define RDAC_LOG_FAILOVER 0
+#define RDAC_LOG_SENSE 2
+
+#define RDAC_LOG_BITS 2
+
+#define RDAC_LOG_LEVEL(SHIFT) \
+ ((rdac_logging >> (SHIFT)) & ((1 << (RDAC_LOG_BITS)) - 1))
+
+#define RDAC_LOG(SHIFT, sdev, f, arg...) \
+do { \
+ if (unlikely(RDAC_LOG_LEVEL(SHIFT))) \
+ sdev_printk(KERN_INFO, sdev, RDAC_NAME ": " f "\n", ## arg); \
+} while (0);
+
static inline struct rdac_dh_data *get_rdac_data(struct scsi_device *sdev)
{
struct scsi_dh_data *scsi_dh_data = sdev->scsi_dh_data;
@@ -469,6 +494,7 @@ static int mode_select_handle_sense(stru
{
struct scsi_sense_hdr sense_hdr;
int err = SCSI_DH_IO, ret;
+ struct rdac_dh_data *h = get_rdac_data(sdev);

ret = scsi_normalize_sense(sensebuf, SCSI_SENSE_BUFFERSIZE, &sense_hdr);
if (!ret)
@@ -497,11 +523,14 @@ static int mode_select_handle_sense(stru
err = SCSI_DH_RETRY;
break;
default:
- sdev_printk(KERN_INFO, sdev,
- "MODE_SELECT failed with sense %02x/%02x/%02x.\n",
- sense_hdr.sense_key, sense_hdr.asc, sense_hdr.ascq);
+ break;
}

+ RDAC_LOG(RDAC_LOG_FAILOVER, sdev, "array %s, ctlr %d, "
+ "MODE_SELECT returned with sense %02x/%02x/%02x",
+ (char *) h->ctlr->array_name, h->ctlr->index,
+ sense_hdr.sense_key, sense_hdr.asc, sense_hdr.ascq);
+
done:
return err;
}
@@ -518,7 +547,9 @@ retry:
if (!rq)
goto done;

- sdev_printk(KERN_INFO, sdev, "%s MODE_SELECT command.\n",
+ RDAC_LOG(RDAC_LOG_FAILOVER, sdev, "array %s, ctlr %d, "
+ "%s MODE_SELECT command",
+ (char *) h->ctlr->array_name, h->ctlr->index,
(retry_cnt == RDAC_RETRY_COUNT) ? "queueing" : "retrying");

err = blk_execute_rq(q, NULL, rq, 1);
@@ -528,8 +559,12 @@ retry:
if (err == SCSI_DH_RETRY && retry_cnt--)
goto retry;
}
- if (err == SCSI_DH_OK)
+ if (err == SCSI_DH_OK) {
h->state = RDAC_STATE_ACTIVE;
+ RDAC_LOG(RDAC_LOG_FAILOVER, sdev, "array %s, ctlr %d, "
+ "MODE_SELECT completed",
+ (char *) h->ctlr->array_name, h->ctlr->index);
+ }

done:
return err;
@@ -567,6 +602,12 @@ static int rdac_check_sense(struct scsi_