From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 01519C433DF for ; Fri, 31 Jul 2020 09:34:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C8DD7208E4 for ; Fri, 31 Jul 2020 09:34:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732161AbgGaJea (ORCPT ); Fri, 31 Jul 2020 05:34:30 -0400 Received: from foss.arm.com ([217.140.110.172]:53780 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727096AbgGaJe3 (ORCPT ); Fri, 31 Jul 2020 05:34:29 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id D21DE31B; Fri, 31 Jul 2020 02:34:28 -0700 (PDT) Received: from [10.37.12.83] (unknown [10.37.12.83]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 7773F3F66E; Fri, 31 Jul 2020 02:34:27 -0700 (PDT) Subject: Re: [RFC PATCH 04/14] coresight: etm4x: Free up argument of etm4_init_arch_data To: mathieu.poirier@linaro.org Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, mike.leach@linaro.org, coresight@lists.linaro.org References: <20200722172040.1299289-1-suzuki.poulose@arm.com> <20200722172040.1299289-5-suzuki.poulose@arm.com> <20200730173131.GA3155687@xps15> From: Suzuki K Poulose Message-ID: Date: Fri, 31 Jul 2020 10:39:14 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 MIME-Version: 1.0 In-Reply-To: <20200730173131.GA3155687@xps15> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07/30/2020 06:31 PM, Mathieu Poirier wrote: > On Wed, Jul 22, 2020 at 06:20:30PM +0100, Suzuki K Poulose wrote: >> etm4_init_arch_data is called early during the device probe, >> even before the coresight_device is registered. Since we are >> about to replace the direct access via abstraction layer, we >> need a way to pass in the csdev_access for the given device. >> Towards this free up the argument, which is already available >> via etmdrvdata[smp_processor_id()]. >> >> Cc: Mathieu Poirier >> Cc: Mike Leach >> Signed-off-by: Suzuki K Poulose >> --- >> drivers/hwtracing/coresight/coresight-etm4x.c | 15 +++++++++++---- >> 1 file changed, 11 insertions(+), 4 deletions(-) >> >> diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c >> index 7bb74c659c4f..67deb4a4e618 100644 >> --- a/drivers/hwtracing/coresight/coresight-etm4x.c >> +++ b/drivers/hwtracing/coresight/coresight-etm4x.c >> @@ -614,7 +614,8 @@ static const struct coresight_ops etm4_cs_ops = { >> .source_ops = &etm4_source_ops, >> }; >> >> -static void etm4_init_arch_data(void *info) >> + >> +static void etm4_init_arch_data(void *__unused) >> { >> u32 etmidr0; >> u32 etmidr1; >> @@ -622,8 +623,14 @@ static void etm4_init_arch_data(void *info) >> u32 etmidr3; >> u32 etmidr4; >> u32 etmidr5; >> - struct etmv4_drvdata *drvdata = info; >> - int i; >> + struct etmv4_drvdata *drvdata; >> + int i, cpu; >> + >> + cpu = raw_smp_processor_id(); > > Can you provide details on the motivation to use the raw_ version over the regular > one? As far as I can see in linux/smp.h there is no difference between them > unless DEBUB_PREEMPT is enabled. Even then the debug version won't complain > since the task is CPU affined. > Right, it is partly my misunderstanding. debug_smp_processor_id() is to detect cases where smp_processor_id() is called in pre-emptible contexts. This is not the case here. So it is fine to use the smp_processor_id(). I will switch to that in the next version. Thanks Suzuki