[PATCH 4.9 028/103] scsi: scsi_dh_alua: always use a 2 second delay before retrying RTPG

Greg Kroah-Hartman
2019-08-22T17:43:45Z

[ 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 <hare@suse.com>
Tested-by: Zhangguanghui <zhang.guanghui@h3c.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@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