From patchwork Mon Mar 23 19:45:07 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Abhishek Pandit-Subedi X-Patchwork-Id: 11453745 X-Patchwork-Delegate: marcel@holtmann.org 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 71F451392 for ; Mon, 23 Mar 2020 19:45:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 49E5420753 for ; Mon, 23 Mar 2020 19:45:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="FQCzKzSn" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727117AbgCWTpR (ORCPT ); Mon, 23 Mar 2020 15:45:17 -0400 Received: from mail-pj1-f65.google.com ([209.85.216.65]:55622 "EHLO mail-pj1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725893AbgCWTpQ (ORCPT ); Mon, 23 Mar 2020 15:45:16 -0400 Received: by mail-pj1-f65.google.com with SMTP id mj6so327682pjb.5 for ; Mon, 23 Mar 2020 12:45:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=Gz4rDOjXchjqPi1nEVVmXK3+btJI8g3SNGoz9O5jtbU=; b=FQCzKzSnrYYmQWC2CSbKEn/Y+a4mEjYl0yrAbXpAW6bEpGUFofnjCIVRVNdfJ6grza 6NQAXeuDPyK+Lgcqz9xjCE+OjQeoi/IKhLMIn8k369vrvYlj3lEoYjsp7iQnSDAYAbwk qgOBdQop3YcOTsD60DA2yneHrqsE2QnNHNaJs= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=Gz4rDOjXchjqPi1nEVVmXK3+btJI8g3SNGoz9O5jtbU=; b=CiLJb2raiDEIsoLS+WZFyez4Gj15uwWqT+ta9UIxYcisbZ3xc7Zea2q+TbD0NVqpR5 dcBwsKDCWPFVwocWBdbxdcFptQmlNWZisf7zRZB1dYwdLxTxjLDU7Cq8XD1tFJBf7JEO YfVpGIn8b6hEs/KVWySkEgZcW09H80Lx4RfLanG1MOuBBFQfg/WES3dcJlgailZqeWdi K7mz51rgcMmWDNMjS+u1yMIbnf7QmoYzALLAitgEye3YONFr/kTuiayExAzazzoW6P12 e4JDnJytP8OvJcbMONQQPtVC9Gp9H8KWFoV8Qwic6i1wPPrIQr1HBgBzUDasZtaKc8jl zLng== X-Gm-Message-State: ANhLgQ2I+FektSMCWcdZ3mGk+v9avaHKVxFnftdgxP7I+zWXffdMSyOC MKJsHXVnHg5v3n1RCArsmut8Zw== X-Google-Smtp-Source: ADFU+vtgxL11HS2OubBV8XWWkYQpV6F4ZBoCjXnruDl0thaI8CAUmp203GJx1kAPo9hxrSPL2dkAyw== X-Received: by 2002:a17:90a:3188:: with SMTP id j8mr1058249pjb.82.1584992714874; Mon, 23 Mar 2020 12:45:14 -0700 (PDT) Received: from apsdesk.mtv.corp.google.com ([2620:15c:202:1:e09a:8d06:a338:aafb]) by smtp.gmail.com with ESMTPSA id s98sm344857pjb.46.2020.03.23.12.45.14 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 23 Mar 2020 12:45:14 -0700 (PDT) From: Abhishek Pandit-Subedi To: marcel@holtmann.org, linux-bluetooth@vger.kernel.org Cc: chromeos-bluetooth-upstreaming@chromium.org, Abhishek Pandit-Subedi , "David S. Miller" , Johan Hedberg , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Jakub Kicinski Subject: [PATCH v3 1/1] Bluetooth: Prioritize SCO traffic Date: Mon, 23 Mar 2020 12:45:07 -0700 Message-Id: <20200323124503.v3.1.I17e2220fd0c0822c76a15ef89b882fb4cfe3fe89@changeid> X-Mailer: git-send-email 2.25.1.696.g5e7596f4ac-goog In-Reply-To: <20200323194507.90944-1-abhishekpandit@chromium.org> References: <20200323194507.90944-1-abhishekpandit@chromium.org> MIME-Version: 1.0 Sender: linux-bluetooth-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-bluetooth@vger.kernel.org When scheduling TX packets, send all SCO/eSCO packets first, check for pending SCO/eSCO packets after every ACL/LE packet and send them if any are pending. This is done to make sure that we can meet SCO deadlines on slow interfaces like UART. If we were to queue up multiple ACL packets without checking for a SCO packet, we might miss the SCO timing. For example: The time it takes to send a maximum size ACL packet (1024 bytes): t = 10/8 * 1024 bytes * 8 bits/byte * 1 packet / baudrate where 10/8 is uart overhead due to start/stop bits per byte Replace t = 3.75ms (SCO deadline), which gives us a baudrate of 2730666. At a baudrate of 3000000, if we didn't check for SCO packets within 1024 bytes, we would miss the 3.75ms timing window. Signed-off-by: Abhishek Pandit-Subedi --- Changes in v3: * Removed hci_sched_sync Changes in v2: * Refactor to check for SCO/eSCO after each ACL/LE packet sent * Enabled SCO priority all the time and removed the sched_limit variable net/bluetooth/hci_core.c | 106 +++++++++++++++++++++------------------ 1 file changed, 57 insertions(+), 49 deletions(-) diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c index dbd2ad3a26ed..9e5d7662a047 100644 --- a/net/bluetooth/hci_core.c +++ b/net/bluetooth/hci_core.c @@ -4239,6 +4239,54 @@ static void __check_timeout(struct hci_dev *hdev, unsigned int cnt) } } +/* Schedule SCO */ +static void hci_sched_sco(struct hci_dev *hdev) +{ + struct hci_conn *conn; + struct sk_buff *skb; + int quote; + + BT_DBG("%s", hdev->name); + + if (!hci_conn_num(hdev, SCO_LINK)) + return; + + while (hdev->sco_cnt && (conn = hci_low_sent(hdev, SCO_LINK, "e))) { + while (quote-- && (skb = skb_dequeue(&conn->data_q))) { + BT_DBG("skb %p len %d", skb, skb->len); + hci_send_frame(hdev, skb); + + conn->sent++; + if (conn->sent == ~0) + conn->sent = 0; + } + } +} + +static void hci_sched_esco(struct hci_dev *hdev) +{ + struct hci_conn *conn; + struct sk_buff *skb; + int quote; + + BT_DBG("%s", hdev->name); + + if (!hci_conn_num(hdev, ESCO_LINK)) + return; + + while (hdev->sco_cnt && (conn = hci_low_sent(hdev, ESCO_LINK, + "e))) { + while (quote-- && (skb = skb_dequeue(&conn->data_q))) { + BT_DBG("skb %p len %d", skb, skb->len); + hci_send_frame(hdev, skb); + + conn->sent++; + if (conn->sent == ~0) + conn->sent = 0; + } + } +} + static void hci_sched_acl_pkt(struct hci_dev *hdev) { unsigned int cnt = hdev->acl_cnt; @@ -4270,6 +4318,10 @@ static void hci_sched_acl_pkt(struct hci_dev *hdev) hdev->acl_cnt--; chan->sent++; chan->conn->sent++; + + /* Send pending SCO packets right away */ + hci_sched_sco(hdev); + hci_sched_esco(hdev); } } @@ -4354,54 +4406,6 @@ static void hci_sched_acl(struct hci_dev *hdev) } } -/* Schedule SCO */ -static void hci_sched_sco(struct hci_dev *hdev) -{ - struct hci_conn *conn; - struct sk_buff *skb; - int quote; - - BT_DBG("%s", hdev->name); - - if (!hci_conn_num(hdev, SCO_LINK)) - return; - - while (hdev->sco_cnt && (conn = hci_low_sent(hdev, SCO_LINK, "e))) { - while (quote-- && (skb = skb_dequeue(&conn->data_q))) { - BT_DBG("skb %p len %d", skb, skb->len); - hci_send_frame(hdev, skb); - - conn->sent++; - if (conn->sent == ~0) - conn->sent = 0; - } - } -} - -static void hci_sched_esco(struct hci_dev *hdev) -{ - struct hci_conn *conn; - struct sk_buff *skb; - int quote; - - BT_DBG("%s", hdev->name); - - if (!hci_conn_num(hdev, ESCO_LINK)) - return; - - while (hdev->sco_cnt && (conn = hci_low_sent(hdev, ESCO_LINK, - "e))) { - while (quote-- && (skb = skb_dequeue(&conn->data_q))) { - BT_DBG("skb %p len %d", skb, skb->len); - hci_send_frame(hdev, skb); - - conn->sent++; - if (conn->sent == ~0) - conn->sent = 0; - } - } -} - static void hci_sched_le(struct hci_dev *hdev) { struct hci_chan *chan; @@ -4436,6 +4440,10 @@ static void hci_sched_le(struct hci_dev *hdev) cnt--; chan->sent++; chan->conn->sent++; + + /* Send pending SCO packets right away */ + hci_sched_sco(hdev); + hci_sched_esco(hdev); } } @@ -4458,9 +4466,9 @@ static void hci_tx_work(struct work_struct *work) if (!hci_dev_test_flag(hdev, HCI_USER_CHANNEL)) { /* Schedule queues and send stuff to HCI driver */ - hci_sched_acl(hdev); hci_sched_sco(hdev); hci_sched_esco(hdev); + hci_sched_acl(hdev); hci_sched_le(hdev); }