Currently, alua_rtpg() can change the 'state' and 'preferred'
values for the current port group _and_ of other port groups
present in the response buffer/descriptors.
However, it reports such changes _only_ for the current port
group (i.e., only for 'pg' but not for 'tmp_pg').
This might cause uncertainty and confusion when going through
the kernel logs for analyzing/debugging scsi_dh_alua behavior,
which is not helpful during support and development scenarios.
So, print such changes for other port groups than the current
one.
This requires finding a scsi_device to call sdev_printk() with
for that other port group. Using 'tmp_pg->rtpg_sdev' is not an
option because in that 'if' conditional the 'tmp_pg' is not in
the ALUA_PG_RUNNING state, so that pointer may be NULL. So the
for-loop over the tmp->pg device_handler structures is used to
find a valid scsi_device that is associated to this port group.
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@xxxxxxxxxxxxxxxxxx>
---
drivers/scsi/device_handler/scsi_dh_alua.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index 0d3508f2e285..c2c9173fd883 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -688,6 +688,7 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg)
if ((tmp_pg == pg) ||
!(tmp_pg->flags & ALUA_PG_RUNNING)) {
struct alua_dh_data *h;
+ struct scsi_device *tmp_pg_sdev = NULL;
tmp_pg->state = desc[0] & 0x0f;
tmp_pg->pref = desc[0] >> 7;
@@ -697,6 +698,17 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg)
/* h->sdev should always be valid */
BUG_ON(!h->sdev);
h->sdev->access_state = desc[0];
+
+ /*
+ * If tmp_pg is not the running pg, and its worker
+ * is not running, tmp_pg->rtpg_sdev might be NULL.
+ * Use another/one associated scsi_device to print
+ * its RTPG information.
+ */
+ if ((tmp_pg != pg) && !tmp_pg_sdev) {
+ tmp_pg_sdev = h->sdev;
+ alua_rtpg_print(tmp_pg_sdev, tmp_pg, NULL);
+ }
}
rcu_read_unlock();
}
--
1.8.3.1
