2014-07-28 13:37:47

by Michal Kazior

Subject: [PATCH] ath10k: improve channel switching

In some cases during heavy tx vdev stop-start
would timeout on vdev synchronization causing
traffic to stall for a few seconds.

Instead of stop-starting use a dedicated vdev
restart command and down vdevs explicitly before
doing so.

This gets rid of the synchronization
warnings/timeouts and makes channel switching
smoother during traffic.

Signed-off-by: Michal Kazior <[email protected]>
---
drivers/net/wireless/ath/ath10k/mac.c | 31 ++++++++++++++++++++++++-------
1 file changed, 24 insertions(+), 7 deletions(-)

diff --git a/drivers/net/wireless/ath/ath10k/mac.c b/drivers/net/wireless/ath/ath10k/mac.c
index 9d61bb1..b76efe2 100644
--- a/drivers/net/wireless/ath/ath10k/mac.c
+++ b/drivers/net/wireless/ath/ath10k/mac.c
@@ -796,7 +796,7 @@ static void ath10k_recalc_radar_detection(struct ath10k *ar)
}
}

-static int ath10k_vdev_start(struct ath10k_vif *arvif)
+static int ath10k_vdev_start_restart(struct ath10k_vif *arvif, bool restart)
{
struct ath10k *ar = arvif->ar;
struct cfg80211_chan_def *chandef = &ar->chandef;
@@ -838,7 +838,11 @@ static int ath10k_vdev_start(struct ath10k_vif *arvif)
arg.vdev_id, arg.channel.freq,
ath10k_wmi_phymode_str(arg.channel.mode));

- ret = ath10k_wmi_vdev_start(ar, &arg);
+ if (restart)
+ ret = ath10k_wmi_vdev_restart(ar, &arg);
+ else
+ ret = ath10k_wmi_vdev_start(ar, &arg);
+
if (ret) {
ath10k_warn("failed to start WMI vdev %i: %d\n",
arg.vdev_id, ret);
@@ -858,6 +862,16 @@ static int ath10k_vdev_start(struct ath10k_vif *arvif)
return ret;
}

+static int ath10k_vdev_start(struct ath10k_vif *arvif)
+{
+ return ath10k_vdev_start_restart(arvif, false);
+}
+
+static int ath10k_vdev_restart(struct ath10k_vif *arvif)
+{
+ return ath10k_vdev_start_restart(arvif, true);
+}
+
static int ath10k_vdev_stop(struct ath10k_vif *arvif)
{
struct ath10k *ar = arvif->ar;
@@ -2582,18 +2596,21 @@ static void ath10k_config_chan(struct ath10k *ar)
if (!arvif->is_started)
continue;

+ if (!arvif->is_up)
+ continue;
+
if (arvif->vdev_type == WMI_VDEV_TYPE_MONITOR)
continue;

- ret = ath10k_vdev_stop(arvif);
+ ret = ath10k_wmi_vdev_down(ar, arvif->vdev_id);
if (ret) {
- ath10k_warn("failed to stop vdev %d: %d\n",
+ ath10k_warn("failed to down vdev %d: %d\n",
arvif->vdev_id, ret);
continue;
}
}

- /* all vdevs are now stopped - now attempt to restart them */
+ /* all vdevs are downed now - attempt to restart and re-up them */

list_for_each_entry(arvif, &ar->arvifs, list) {
if (!arvif->is_started)
@@ -2602,9 +2619,9 @@ static void ath10k_config_chan(struct ath10k *ar)
if (arvif->vdev_type == WMI_VDEV_TYPE_MONITOR)
continue;

- ret = ath10k_vdev_start(arvif);
+ ret = ath10k_vdev_restart(arvif);
if (ret) {
- ath10k_warn("failed to start vdev %d: %d\n",
+ ath10k_warn("failed to restart vdev %d: %d\n",
arvif->vdev_id, ret);
continue;
}
--
1.8.5.3

2014-08-02 06:12:48

by Kalle Valo

Subject: Re: [PATCH] ath10k: improve channel switching

Michal Kazior <[email protected]> writes:

> In some cases during heavy tx vdev stop-start
> would timeout on vdev synchronization causing
> traffic to stall for a few seconds.
>
> Instead of stop-starting use a dedicated vdev
> restart command and down vdevs explicitly before
> doing so.
>
> This gets rid of the synchronization
> warnings/timeouts and makes channel switching
> smoother during traffic.
>
> Signed-off-by: Michal Kazior <[email protected]>

Thanks, applied.

--
Kalle Valo