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Message-ID: <1423143210.31870.51.camel@edumazet-glaptop2.roam.corp.google.com> (sfid-20150205_143339_999333_D0B17B87)
Subject: Re: Throughput regression with `tcp: refine TSO autosizing`
From: Eric Dumazet <eric.dumazet@gmail.com>
To: Michal Kazior <michal.kazior@tieto.com>
Cc: Neal Cardwell <ncardwell@google.com>,
	linux-wireless <linux-wireless@vger.kernel.org>,
	Network Development <netdev@vger.kernel.org>,
	eyalpe@dev.mellanox.co.il
Date: Thu, 05 Feb 2015 05:33:30 -0800
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On Thu, 2015-02-05 at 05:19 -0800, Eric Dumazet wrote:

> 
> TCP could  eventually dynamically adjust the tcp_limit_output_bytes,
> using a per flow dynamic value, but I would rather not add a kludge in
> TCP stack only to deal with a possible bug in ath10k driver.
> 
> niu has a similar issue and simply had to call skb_orphan() :
> 
> drivers/net/ethernet/sun/niu.c:6669:            skb_orphan(skb);

In your case that might be the place :

diff --git a/drivers/net/wireless/ath/ath10k/htt_tx.c b/drivers/net/wireless/ath/ath10k/htt_tx.c
index 4bc51d8a14a3..cbda7a87d5a1 100644
--- a/drivers/net/wireless/ath/ath10k/htt_tx.c
+++ b/drivers/net/wireless/ath/ath10k/htt_tx.c
@@ -468,6 +468,7 @@ int ath10k_htt_tx(struct ath10k_htt *htt, struct sk_buff *msdu)
 	msdu_id = res;
 	htt->pending_tx[msdu_id] = msdu;
 	spin_unlock_bh(&htt->tx_lock);
+	skb_orphan(msdu);
 
 	prefetch_len = min(htt->prefetch_len, msdu->len);
 	prefetch_len = roundup(prefetch_len, 4);