[PATCH AUTOSEL 4.9 20/22] scsi: scsi_dh_alua: always use a 2 second delay before retrying RTPG

[Sasha Levin]

From: Hannes Reinecke <h...@suse.de>

[ Upstream commit 20122994e38aef0ae50555884d287adde6641c94 ]

Retrying immediately after we've received a 'transitioning' sense code is
pretty much pointless, we should always use a delay before retrying.  So
ensure the default delay is applied before retrying.

Signed-off-by: Hannes Reinecke <h...@suse.com>
Tested-by: Zhangguanghui <zhang.guang...@h3c.com>
Signed-off-by: Martin K. Petersen <martin.peter...@oracle.com>
Signed-off-by: Sasha Levin <sas...@kernel.org>
---
 drivers/scsi/device_handler/scsi_dh_alua.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c 
b/drivers/scsi/device_handler/scsi_dh_alua.c
index d3145799b92fa..98787588247bf 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -53,6 +53,7 @@
 #define ALUA_FAILOVER_TIMEOUT          60
 #define ALUA_FAILOVER_RETRIES          5
 #define ALUA_RTPG_DELAY_MSECS          5
+#define ALUA_RTPG_RETRY_DELAY          2
 
 /* device handler flags */
 #define ALUA_OPTIMIZE_STPG             0x01
@@ -681,7 +682,7 @@ static int alua_rtpg(struct scsi_device *sdev, struct 
alua_port_group *pg)
        case SCSI_ACCESS_STATE_TRANSITIONING:
                if (time_before(jiffies, pg->expiry)) {
                        /* State transition, retry */
-                       pg->interval = 2;
+                       pg->interval = ALUA_RTPG_RETRY_DELAY;
                        err = SCSI_DH_RETRY;
                } else {
                        struct alua_dh_data *h;
@@ -809,6 +810,8 @@ static void alua_rtpg_work(struct work_struct *work)
                                spin_lock_irqsave(&pg->lock, flags);
                                pg->flags &= ~ALUA_PG_RUNNING;
                                pg->flags |= ALUA_PG_RUN_RTPG;
+                               if (!pg->interval)
+                                       pg->interval = ALUA_RTPG_RETRY_DELAY;
                                spin_unlock_irqrestore(&pg->lock, flags);
                                queue_delayed_work(alua_wq, &pg->rtpg_work,
                                                   pg->interval * HZ);
@@ -820,6 +823,8 @@ static void alua_rtpg_work(struct work_struct *work)
                spin_lock_irqsave(&pg->lock, flags);
                if (err == SCSI_DH_RETRY || pg->flags & ALUA_PG_RUN_RTPG) {
                        pg->flags &= ~ALUA_PG_RUNNING;
+                       if (!pg->interval && !(pg->flags & ALUA_PG_RUN_RTPG))
+                               pg->interval = ALUA_RTPG_RETRY_DELAY;
                        pg->flags |= ALUA_PG_RUN_RTPG;
                        spin_unlock_irqrestore(&pg->lock, flags);
                        queue_delayed_work(alua_wq, &pg->rtpg_work,
-- 
2.20.1