Path checkers will check paths of a port group in unavailable/standby
state more frequently (as they are 'failed') - possibly for a long or
indefinite period of time, and/or for a large number of paths.
That might flood the kernel log with scsi_dh_alua RTPG state messages,
due to the recheck scheduled in alua_check_sense() to update PG state.
So, do not to print such message if unavailable/standby state remains
(i.e., the PG did not transition to/from such states). All other cases
continue to be printed.
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@xxxxxxxxxxxxxxxxxx>
---
v2:
- changed v1's alua_state_remains() into alua_rtpg_print_check(),
which includes in the states (not) to print for (deduplicates code).
- added support for Standby state too (requested in patch 1 of this set)
(Bart Van Assche <Bart.VanAssche@xxxxxxxxxxx>)
- remove superfluous parentheses in return statement.
(Bart Van Assche <Bart.VanAssche@xxxxxxxxxxx>)
- remove likely() hint
(Bart Van Assche <Bart.VanAssche@xxxxxxxxxxx>)
drivers/scsi/device_handler/scsi_dh_alua.c | 35 ++++++++++++++++++++++++++----
1 file changed, 31 insertions(+), 4 deletions(-)
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index 937341ddb767..e0bf0827a980 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -572,6 +572,30 @@ static void alua_rtpg_print_supported(struct scsi_device *sdev,
}
/*
+ * alua_rtpg_print_check - Whether to print RTPG state information
+ * on particular state transitions.
+ * @old_state: the old state value.
+ * @new_state: the new state value.
+ */
+static bool alua_rtpg_print_check(int old_state, int new_state)
+{
+ /*
+ * Do not print RTPG state information in case
+ * state remains either unavailable or standby.
+ *
+ * Print it for everything else.
+ */
+
+ switch (old_state) {
+ case SCSI_ACCESS_STATE_UNAVAILABLE:
+ case SCSI_ACCESS_STATE_STANDBY:
+ return old_state != new_state;
+ default:
+ return 1;
+ }
+}
+
+/*
* alua_rtpg - Evaluate REPORT TARGET GROUP STATES
* @sdev: the device to be evaluated.
*
@@ -706,6 +730,7 @@ 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;
+ int tmp_pg_state_orig = tmp_pg->state;
tmp_pg->state = desc[0] & 0x0f;
tmp_pg->pref = desc[0] >> 7;
@@ -718,10 +743,12 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg)
}
rcu_read_unlock();
- if (tmp_pg == pg)
- alua_rtpg_print_supported(sdev, tmp_pg, desc[1]);
- else
- alua_rtpg_print(sdev, tmp_pg);
+ if (alua_rtpg_print_check(tmp_pg_state_orig, tmp_pg->state)) {
+ if (tmp_pg == pg)
+ alua_rtpg_print_supported(sdev, tmp_pg, desc[1]);
+ else
+ alua_rtpg_print(sdev, tmp_pg);
+ }
}
spin_unlock_irqrestore(&tmp_pg->lock, flags);
}
--
1.8.3.1
