2016-03-17 09:49:00

by Michal Kazior

Subject: [PATCH 0/2] ath10k: fix tx hangs

Hi,

My recent wake-tx-queue/pull-push related patches
introduced a regression that can cause tx to hang
under certain circumstances.


Michal Kazior (2):
ath10k: fix tx hang
ath10k: fix pull-push tx threshold handling

drivers/net/wireless/ath/ath10k/mac.c | 22 +++++++++++-----------
1 file changed, 11 insertions(+), 11 deletions(-)

--
2.1.4

2016-03-17 09:49:01

by Michal Kazior

Subject: [PATCH 1/2] ath10k: fix tx hang

The wake_tx_queue/push_pending logic had a bug
which could stop queues indefinitely effectivelly
breaking traffic.

Fixes: 299468782d94 ("ath10k: implement wake_tx_queue")
Signed-off-by: Michal Kazior <[email protected]>
---
drivers/net/wireless/ath/ath10k/mac.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/net/wireless/ath/ath10k/mac.c b/drivers/net/wireless/ath/ath10k/mac.c
index ebff9c0a0784..74dd010a9188 100644
--- a/drivers/net/wireless/ath/ath10k/mac.c
+++ b/drivers/net/wireless/ath/ath10k/mac.c
@@ -3779,13 +3779,13 @@ void ath10k_mac_tx_push_pending(struct ath10k *ar)
}

list_del_init(&artxq->list);
+ if (ret != -ENOENT)
+ list_add_tail(&artxq->list, &ar->txqs);
+
ath10k_htt_tx_txq_update(hw, txq);

- if (artxq == last || (ret < 0 && ret != -ENOENT)) {
- if (ret != -ENOENT)
- list_add_tail(&artxq->list, &ar->txqs);
+ if (artxq == last || (ret < 0 && ret != -ENOENT))
break;
- }
}

rcu_read_unlock();
--
2.1.4

2016-03-17 09:49:02

by Michal Kazior

Subject: [PATCH 2/2] ath10k: fix pull-push tx threshold handling

This prevents tx hangs or hiccups if pull-push
supporting firmware defines per-txq thresholds or
switches modes dynamically.

Fixes: 299468782d94 ("ath10k: implement wake_tx_queue")
Signed-off-by: Michal Kazior <[email protected]>
---
drivers/net/wireless/ath/ath10k/mac.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/net/wireless/ath/ath10k/mac.c b/drivers/net/wireless/ath/ath10k/mac.c
index 74dd010a9188..4d51b92e67e0 100644
--- a/drivers/net/wireless/ath/ath10k/mac.c
+++ b/drivers/net/wireless/ath/ath10k/mac.c
@@ -3772,7 +3772,8 @@ void ath10k_mac_tx_push_pending(struct ath10k *ar)

/* Prevent aggressive sta/tid taking over tx queue */
max = 16;
- while (max--) {
+ ret = 0;
+ while (ath10k_mac_tx_can_push(hw, txq) && max--) {
ret = ath10k_mac_tx_push_txq(hw, txq);
if (ret < 0)
break;
@@ -4015,14 +4016,13 @@ static void ath10k_mac_op_wake_tx_queue(struct ieee80211_hw *hw,
struct ath10k *ar = hw->priv;
struct ath10k_txq *artxq = (void *)txq->drv_priv;

- if (ath10k_mac_tx_can_push(hw, txq)) {
- spin_lock_bh(&ar->txqs_lock);
- if (list_empty(&artxq->list))
- list_add_tail(&artxq->list, &ar->txqs);
- spin_unlock_bh(&ar->txqs_lock);
+ spin_lock_bh(&ar->txqs_lock);
+ if (list_empty(&artxq->list))
+ list_add_tail(&artxq->list, &ar->txqs);
+ spin_unlock_bh(&ar->txqs_lock);

+ if (ath10k_mac_tx_can_push(hw, txq))
tasklet_schedule(&ar->htt.txrx_compl_task);
- }

ath10k_htt_tx_txq_update(hw, txq);
}
--
2.1.4

2016-03-23 12:09:35

by Kalle Valo

Subject: Re: [PATCH 0/2] ath10k: fix tx hangs

Michal Kazior <[email protected]> writes:

> My recent wake-tx-queue/pull-push related patches
> introduced a regression that can cause tx to hang
> under certain circumstances.
>
>
> Michal Kazior (2):
> ath10k: fix tx hang
> ath10k: fix pull-push tx threshold handling

Both applied, thanks.

--
Kalle Valo