From 3f04950f32d5d592ab4fcaecac2178558a6f7437 Mon Sep 17 00:00:00 2001
From: Niklas Cassel <niklas.cassel@linaro.org>
Date: Mon, 18 Jun 2018 17:00:49 +0300
Subject: [PATCH] ath10k: transmit queued frames after processing rx packets
Git-commit: 3f04950f32d5d592ab4fcaecac2178558a6f7437
Patch-mainline: v4.19-rc1
References: FATE#326906
When running iperf on ath10k SDIO, TX can stop working:
iperf -c 192.168.1.1 -i 1 -t 20 -w 10K
[ 3] 0.0- 1.0 sec 2.00 MBytes 16.8 Mbits/sec
[ 3] 1.0- 2.0 sec 3.12 MBytes 26.2 Mbits/sec
[ 3] 2.0- 3.0 sec 3.25 MBytes 27.3 Mbits/sec
[ 3] 3.0- 4.0 sec 655 KBytes 5.36 Mbits/sec
[ 3] 4.0- 5.0 sec 0.00 Bytes 0.00 bits/sec
[ 3] 5.0- 6.0 sec 0.00 Bytes 0.00 bits/sec
[ 3] 6.0- 7.0 sec 0.00 Bytes 0.00 bits/sec
[ 3] 7.0- 8.0 sec 0.00 Bytes 0.00 bits/sec
[ 3] 8.0- 9.0 sec 0.00 Bytes 0.00 bits/sec
[ 3] 9.0-10.0 sec 0.00 Bytes 0.00 bits/sec
[ 3] 0.0-10.3 sec 9.01 MBytes 7.32 Mbits/sec
There are frames in the ieee80211_txq and there are frames that have
been removed from from this queue, but haven't yet been sent on the wire
(num_pending_tx).
When num_pending_tx reaches max_num_pending_tx, we will stop the queues
by calling ieee80211_stop_queues().
As frames that have previously been sent for transmission
(num_pending_tx) are completed, we will decrease num_pending_tx and wake
the queues by calling ieee80211_wake_queue(). ieee80211_wake_queue()
does not call wake_tx_queue, so we might still have frames in the
queue at this point.
While the queues were stopped, the socket buffer might have filled up,
and in order for user space to write more, we need to free the frames
in the queue, since they are accounted to the socket. In order to free
them, we first need to transmit them.
This problem cannot be reproduced on low-latency devices, e.g. pci,
since they call ath10k_mac_tx_push_pending() from
ath10k_htt_txrx_compl_task(). ath10k_htt_txrx_compl_task() is not called
on high-latency devices.
Fix the problem by calling ath10k_mac_tx_push_pending(), after
processing rx packets, just like for low-latency devices, also in the
SDIO case. Since we are calling ath10k_mac_tx_push_pending() directly,
we also need to export it.
Signed-off-by: Niklas Cassel <niklas.cassel@linaro.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/net/wireless/ath/ath10k/mac.c | 1 +
drivers/net/wireless/ath/ath10k/sdio.c | 3 +++
2 files changed, 4 insertions(+)
diff --git a/drivers/net/wireless/ath/ath10k/mac.c b/drivers/net/wireless/ath/ath10k/mac.c
index f31ae3be4778..a6a34486eca3 100644
--- a/drivers/net/wireless/ath/ath10k/mac.c
+++ b/drivers/net/wireless/ath/ath10k/mac.c
@@ -4047,6 +4047,7 @@ void ath10k_mac_tx_push_pending(struct ath10k *ar)
rcu_read_unlock();
spin_unlock_bh(&ar->txqs_lock);
}
+EXPORT_SYMBOL(ath10k_mac_tx_push_pending);
/************/
/* Scanning */
diff --git a/drivers/net/wireless/ath/ath10k/sdio.c b/drivers/net/wireless/ath/ath10k/sdio.c
index d612ce8c9cff..2856c75f9011 100644
--- a/drivers/net/wireless/ath/ath10k/sdio.c
+++ b/drivers/net/wireless/ath/ath10k/sdio.c
@@ -30,6 +30,7 @@
#include "debug.h"
#include "hif.h"
#include "htc.h"
+#include "mac.h"
#include "targaddrs.h"
#include "trace.h"
#include "sdio.h"
@@ -1342,6 +1343,8 @@ static void ath10k_sdio_irq_handler(struct sdio_func *func)
break;
} while (time_before(jiffies, timeout) && !done);
+ ath10k_mac_tx_push_pending(ar);
+
sdio_claim_host(ar_sdio->func);
if (ret && ret != -ECANCELED)
--
2.19.2