From patchwork Wed May 18 16:44:17 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sai Prakash Ranjan X-Patchwork-Id: 12853873 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9F87CC433FE for ; Wed, 18 May 2022 16:45:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240485AbiERQpi (ORCPT ); Wed, 18 May 2022 12:45:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46096 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240469AbiERQp2 (ORCPT ); Wed, 18 May 2022 12:45:28 -0400 Received: from alexa-out.qualcomm.com (alexa-out.qualcomm.com [129.46.98.28]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id ABEB41FE1C7; Wed, 18 May 2022 09:45:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; i=@quicinc.com; q=dns/txt; s=qcdkim; t=1652892326; x=1684428326; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=a/+b7pV2Bo1HIRQnpM4Y15NOBUEBq9pVgDGvjKkqQtY=; b=gdA5kF/OBSCGL5lbbaJawtm0ywDnyH28akklNjxqCLaQ/58KSe51b6XV Hy5BHUQS8EtmQxMSb9XuRSlR3MZY44MFbgc16tvXfEbN89o0mT9+wXnIj wOI1IHbJjKy7LWC/klBq5fKESTSIuLOZka5AVbf8laYuV8lcBE0IWV4tp Y=; Received: from ironmsg-lv-alpha.qualcomm.com ([10.47.202.13]) by alexa-out.qualcomm.com with ESMTP; 18 May 2022 09:45:26 -0700 X-QCInternal: smtphost Received: from nasanex01c.na.qualcomm.com ([10.47.97.222]) by ironmsg-lv-alpha.qualcomm.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 May 2022 09:45:25 -0700 Received: from nalasex01a.na.qualcomm.com (10.47.209.196) by nasanex01c.na.qualcomm.com (10.47.97.222) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.986.22; Wed, 18 May 2022 09:45:25 -0700 Received: from blr-ubuntu-253.qualcomm.com (10.80.80.8) by nalasex01a.na.qualcomm.com (10.47.209.196) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.986.22; Wed, 18 May 2022 09:45:20 -0700 From: Sai Prakash Ranjan To: , , CC: , , , , , , , , , , Sai Prakash Ranjan , Bjorn Andersson Subject: [PATCHv15 8/9] serial: qcom_geni_serial: Disable MMIO tracing for geni serial Date: Wed, 18 May 2022 22:14:17 +0530 Message-ID: <2db93219cdeabe1c267c7f627e26b8d7fc7caa23.1652891705.git.quic_saipraka@quicinc.com> X-Mailer: git-send-email 2.33.1 In-Reply-To: References: MIME-Version: 1.0 X-Originating-IP: [10.80.80.8] X-ClientProxiedBy: nasanex01a.na.qualcomm.com (10.52.223.231) To nalasex01a.na.qualcomm.com (10.47.209.196) Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org Disable MMIO tracing for geni serial driver to prevent excessive logging. Any access over serial console would involve a lot of TX and RX register accesses (and few others), so these MMIO read/write trace events in these drivers cause a lot of unwanted noise because of the high frequency of such operations and it is not very useful tracing these events for such drivers. Given we want to enable these trace events on development devices (maybe not production devices) where performance also really matters so that we don't regress other components by wasting CPU cycles and memory collecting these traces, it makes more sense to disable these traces from such drivers. Also another reason to disable these traces would be to prevent recursive tracing when we display the trace buffer containing these MMIO trace events since writing onto serial console would further record MMIO traces. Cc: Bjorn Andersson Signed-off-by: Sai Prakash Ranjan --- drivers/tty/serial/qcom_geni_serial.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c index 1543a6028856..75272585c3c3 100644 --- a/drivers/tty/serial/qcom_geni_serial.c +++ b/drivers/tty/serial/qcom_geni_serial.c @@ -1,6 +1,9 @@ // SPDX-License-Identifier: GPL-2.0 // Copyright (c) 2017-2018, The Linux foundation. All rights reserved. +/* Disable MMIO tracing to prevent excessive logging of unwanted MMIO traces */ +#define __DISABLE_TRACE_MMIO__ + #include #include #include