[PATCH AUTOSEL for 4.4 049/101] target: fix ALUA transition timeout handling

From: alexander . levin
Date: Thu Dec 07 2017 - 11:44:04 EST


From: Mike Christie <mchristi@xxxxxxxxxx>

[ Upstream commit d7175373f2745ed4abe5b388d5aabd06304f801e ]

The implicit transition time tells initiators the min time
to wait before timing out a transition. We currently schedule
the transition to occur in tg_pt_gp_implicit_trans_secs
seconds so there is no room for delays. If
core_alua_do_transition_tg_pt_work->core_alua_update_tpg_primary_metadata
needs to write out info to a remote file, then the initiator can
easily time out the operation.

Signed-off-by: Mike Christie <mchristi@xxxxxxxxxx>
Signed-off-by: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
---
drivers/target/target_core_alua.c | 23 ++++++++---------------
include/target/target_core_base.h | 2 +-
2 files changed, 9 insertions(+), 16 deletions(-)

diff --git a/drivers/target/target_core_alua.c b/drivers/target/target_core_alua.c
index 3dad73448ea5..8eec0162acb1 100644
--- a/drivers/target/target_core_alua.c
+++ b/drivers/target/target_core_alua.c
@@ -1010,7 +1010,7 @@ static void core_alua_queue_state_change_ua(struct t10_alua_tg_pt_gp *tg_pt_gp)
static void core_alua_do_transition_tg_pt_work(struct work_struct *work)
{
struct t10_alua_tg_pt_gp *tg_pt_gp = container_of(work,
- struct t10_alua_tg_pt_gp, tg_pt_gp_transition_work.work);
+ struct t10_alua_tg_pt_gp, tg_pt_gp_transition_work);
struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
bool explicit = (tg_pt_gp->tg_pt_gp_alua_access_status ==
ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG);
@@ -1073,13 +1073,12 @@ static int core_alua_do_transition_tg_pt(
/*
* Flush any pending transitions
*/
- if (!explicit && tg_pt_gp->tg_pt_gp_implicit_trans_secs &&
- atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state) ==
+ if (!explicit && atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state) ==
ALUA_ACCESS_STATE_TRANSITION) {
/* Just in case */
tg_pt_gp->tg_pt_gp_alua_pending_state = new_state;
tg_pt_gp->tg_pt_gp_transition_complete = &wait;
- flush_delayed_work(&tg_pt_gp->tg_pt_gp_transition_work);
+ flush_work(&tg_pt_gp->tg_pt_gp_transition_work);
wait_for_completion(&wait);
tg_pt_gp->tg_pt_gp_transition_complete = NULL;
return 0;
@@ -1114,15 +1113,9 @@ static int core_alua_do_transition_tg_pt(
atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
spin_unlock(&dev->t10_alua.tg_pt_gps_lock);

- if (!explicit && tg_pt_gp->tg_pt_gp_implicit_trans_secs) {
- unsigned long transition_tmo;
-
- transition_tmo = tg_pt_gp->tg_pt_gp_implicit_trans_secs * HZ;
- schedule_delayed_work(&tg_pt_gp->tg_pt_gp_transition_work,
- transition_tmo);
- } else {
+ schedule_work(&tg_pt_gp->tg_pt_gp_transition_work);
+ if (explicit) {
tg_pt_gp->tg_pt_gp_transition_complete = &wait;
- schedule_delayed_work(&tg_pt_gp->tg_pt_gp_transition_work, 0);
wait_for_completion(&wait);
tg_pt_gp->tg_pt_gp_transition_complete = NULL;
}
@@ -1690,8 +1683,8 @@ struct t10_alua_tg_pt_gp *core_alua_allocate_tg_pt_gp(struct se_device *dev,
mutex_init(&tg_pt_gp->tg_pt_gp_md_mutex);
spin_lock_init(&tg_pt_gp->tg_pt_gp_lock);
atomic_set(&tg_pt_gp->tg_pt_gp_ref_cnt, 0);
- INIT_DELAYED_WORK(&tg_pt_gp->tg_pt_gp_transition_work,
- core_alua_do_transition_tg_pt_work);
+ INIT_WORK(&tg_pt_gp->tg_pt_gp_transition_work,
+ core_alua_do_transition_tg_pt_work);
tg_pt_gp->tg_pt_gp_dev = dev;
atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED);
@@ -1799,7 +1792,7 @@ void core_alua_free_tg_pt_gp(
dev->t10_alua.alua_tg_pt_gps_counter--;
spin_unlock(&dev->t10_alua.tg_pt_gps_lock);

- flush_delayed_work(&tg_pt_gp->tg_pt_gp_transition_work);
+ flush_work(&tg_pt_gp->tg_pt_gp_transition_work);

/*
* Allow a struct t10_alua_tg_pt_gp_member * referenced by
diff --git a/include/target/target_core_base.h b/include/target/target_core_base.h
index 8555321306fb..9982a2bcb880 100644
--- a/include/target/target_core_base.h
+++ b/include/target/target_core_base.h
@@ -299,7 +299,7 @@ struct t10_alua_tg_pt_gp {
struct list_head tg_pt_gp_lun_list;
struct se_lun *tg_pt_gp_alua_lun;
struct se_node_acl *tg_pt_gp_alua_nacl;
- struct delayed_work tg_pt_gp_transition_work;
+ struct work_struct tg_pt_gp_transition_work;
struct completion *tg_pt_gp_transition_complete;
};

--
2.11.0