Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1034141AbcJ2ONr (ORCPT ); Sat, 29 Oct 2016 10:13:47 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:49786 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030257AbcJ2Nwf (ORCPT ); Sat, 29 Oct 2016 09:52:35 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Rajkumar Manoharan , Kalle Valo Subject: [PATCH 4.8 054/125] ath10k: fix throughput regression in multi client mode Date: Sat, 29 Oct 2016 09:49:32 -0400 Message-Id: <20161029134949.436049185@linuxfoundation.org> X-Mailer: git-send-email 2.10.1 In-Reply-To: <20161029134947.232372651@linuxfoundation.org> References: <20161029134947.232372651@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2100 Lines: 54 4.8-stable review patch. If anyone has any objections, please let me know. ------------------ From: Rajkumar Manoharan commit 18f53fe0f30331e826b075709ed7b26b9283235e upstream. commit 7a0adc83f34d ("ath10k: improve tx scheduling") is causing severe throughput drop in multi client mode. This issue is originally reported in veriwave setup with 50 clients with TCP downlink traffic. While increasing number of clients, the average throughput drops gradually. With 50 clients, the combined peak throughput is decreased to 98 Mbps whereas reverting given commit restored it to 550 Mbps. Processing txqs for every tx completion is causing overhead. Ideally for management frame tx completion, pending txqs processing can be avoided. The change partly reverts the commit "ath10k: improve tx scheduling". Processing pending txqs after all skbs tx completion will yeild enough room to burst tx frames. Fixes: 7a0adc83f34d ("ath10k: improve tx scheduling") Signed-off-by: Rajkumar Manoharan Signed-off-by: Kalle Valo Signed-off-by: Greg Kroah-Hartman --- drivers/net/wireless/ath/ath10k/htt_rx.c | 2 ++ drivers/net/wireless/ath/ath10k/txrx.c | 2 -- 2 files changed, 2 insertions(+), 2 deletions(-) --- a/drivers/net/wireless/ath/ath10k/htt_rx.c +++ b/drivers/net/wireless/ath/ath10k/htt_rx.c @@ -2394,6 +2394,8 @@ static void ath10k_htt_txrx_compl_task(u skb_queue_splice_init(&htt->rx_in_ord_compl_q, &rx_ind_q); spin_unlock_irqrestore(&htt->rx_in_ord_compl_q.lock, flags); + ath10k_mac_tx_push_pending(ar); + spin_lock_irqsave(&htt->tx_fetch_ind_q.lock, flags); skb_queue_splice_init(&htt->tx_fetch_ind_q, &tx_ind_q); spin_unlock_irqrestore(&htt->tx_fetch_ind_q.lock, flags); --- a/drivers/net/wireless/ath/ath10k/txrx.c +++ b/drivers/net/wireless/ath/ath10k/txrx.c @@ -119,8 +119,6 @@ int ath10k_txrx_tx_unref(struct ath10k_h ieee80211_tx_status(htt->ar->hw, msdu); /* we do not own the msdu anymore */ - ath10k_mac_tx_push_pending(ar); - return 0; }