From patchwork Tue Nov 19 15:47:44 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Markus Theil X-Patchwork-Id: 11252379 X-Patchwork-Delegate: nbd@nbd.name Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 05DF8109A for ; Tue, 19 Nov 2019 15:48:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D9B57222AB for ; Tue, 19 Nov 2019 15:48:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728560AbfKSPsD (ORCPT ); Tue, 19 Nov 2019 10:48:03 -0500 Received: from smail.rz.tu-ilmenau.de ([141.24.186.67]:43691 "EHLO smail.rz.tu-ilmenau.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728187AbfKSPsD (ORCPT ); Tue, 19 Nov 2019 10:48:03 -0500 Received: from localhost.localdomain (unknown [141.24.207.101]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smail.rz.tu-ilmenau.de (Postfix) with ESMTPSA id F0D3C58007E; Tue, 19 Nov 2019 16:48:00 +0100 (CET) From: Markus Theil To: nbd@nbd.name Cc: linux-wireless@vger.kernel.org, lorenzo.bianconi@redhat.com, Stanislaw Gruszka , Markus Theil Subject: [PATCH v6 3/5] mt76: mt76x02: remove a copy call for usb speedup Date: Tue, 19 Nov 2019 16:47:44 +0100 Message-Id: <20191119154746.20821-4-markus.theil@tu-ilmenau.de> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20191119154746.20821-1-markus.theil@tu-ilmenau.de> References: <20191119154746.20821-1-markus.theil@tu-ilmenau.de> MIME-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org This patch removes a mt76_wr_copy call from the beacon path to hw. The skb which is used in this place gets therefore build with txwi inside its data. For mt76 usb drivers, this saves one synchronuous copy call over usb, which lets the beacon work complete faster. In mmio case, there is not enough headroom to put the txwi into the skb, it is therefore using an additional mt76_wr_copy, which is fast over mmio. Thanks Stanislaw for pointing this out. Signed-off-by: Markus Theil --- .../wireless/mediatek/mt76/mt76x02_beacon.c | 20 +++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-) diff --git a/drivers/net/wireless/mediatek/mt76/mt76x02_beacon.c b/drivers/net/wireless/mediatek/mt76/mt76x02_beacon.c index 09013adae854..422d53111229 100644 --- a/drivers/net/wireless/mediatek/mt76/mt76x02_beacon.c +++ b/drivers/net/wireless/mediatek/mt76/mt76x02_beacon.c @@ -26,15 +26,27 @@ static int mt76x02_write_beacon(struct mt76x02_dev *dev, int offset, struct sk_buff *skb) { int beacon_len = dev->beacon_ops->slot_size; - struct mt76x02_txwi txwi; if (WARN_ON_ONCE(beacon_len < skb->len + sizeof(struct mt76x02_txwi))) return -ENOSPC; - mt76x02_mac_write_txwi(dev, &txwi, skb, NULL, NULL, skb->len); + /* USB devices already reserve enough skb headroom for txwi's. This + * helps to save slow copies over USB. + */ + if (mt76_is_usb(dev)) { + struct mt76x02_txwi *txwi; + + mt76_insert_hdr_pad(skb); + txwi = (struct mt76x02_txwi *)(skb->data - sizeof(*txwi)); + mt76x02_mac_write_txwi(dev, txwi, skb, NULL, NULL, skb->len); + skb_push(skb, sizeof(*txwi)); + } else { + struct mt76x02_txwi txwi; - mt76_wr_copy(dev, offset, &txwi, sizeof(txwi)); - offset += sizeof(txwi); + mt76x02_mac_write_txwi(dev, &txwi, skb, NULL, NULL, skb->len); + mt76_wr_copy(dev, offset, &txwi, sizeof(txwi)); + offset += sizeof(txwi); + } mt76_wr_copy(dev, offset, skb->data, skb->len); return 0;