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[23.128.96.18]) by mx.google.com with ESMTP id qk42si23605473ejc.539.2021.11.01.04.01.35; Mon, 01 Nov 2021 04:02:01 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@linaro.org header.s=google header.b=ZOPdrP9t; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linaro.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231817AbhKALCQ (ORCPT + 99 others); Mon, 1 Nov 2021 07:02:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37248 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230520AbhKALCQ (ORCPT ); Mon, 1 Nov 2021 07:02:16 -0400 Received: from mail-pg1-x52b.google.com (mail-pg1-x52b.google.com [IPv6:2607:f8b0:4864:20::52b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F2441C061714 for ; Mon, 1 Nov 2021 03:59:42 -0700 (PDT) Received: by mail-pg1-x52b.google.com with SMTP id j9so8718056pgh.1 for ; Mon, 01 Nov 2021 03:59:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=Du3RdDKeh8d/WwM1bhUDKYYDQzg7en92iJDHOWcBOyo=; b=ZOPdrP9trG9iG2RXxn/odr2iVHSdmsIZMm6sKg2WEzvoH9qJpVF5Lo6TJEW/+RTrCH 0t4gzaB5v0+6vuXoTm6U4nMq2w8By79rxMJUfcB3gg6GZ+YkEokPM0EeNi58s4Bgb/Tm UNQ4pVa43n0SR2iQcD5CcLwGHUasv2mizrAvHra1IfHABknLYmE2ZTffOjKo6cPQEZ6L i6lHcjNi+EdRQAT/NnfrId5t91DTDOwBUN0Br2/rrJgbAbTbnVZTerpzNniw8eyi1rN8 sSjjh6/XsWYuDDVXfh1WZuSGDxCCCyAtFo+XR4izv5NEVA+1pEMsuPSaZDmgPXonFWGP jM/Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=Du3RdDKeh8d/WwM1bhUDKYYDQzg7en92iJDHOWcBOyo=; b=i0z4VckrpWCYq2Rn4yNq/I2vEEN3aGKIC/u+zt4Wk3GVhAqV7aNON6h/ng9GfvTgXM 3V8qPt3HT6LzIPRvq0ziYxHPP1mhv/JEXKtyP7c6I6KIy8q5NF5Z2ZZpPofNSrZYWn1z MKkQeQhFKVtc3nE6aFNd2OfifNtELE2bhepccaCeDTOzei/LattqPNI8WK9ALp2A1sJY 75Cp/6B3ZzbAsg8nUseC1hIwmloSwyQ/iMuS3/qh3heqsO8ftVHP1WhkmdeITROJfLcu NoX26GhvTRhSPdnRjMEnyjOKHuthGmDoP5fzuPucN4NmUenymARF3XUB2IIkpvfY99UE 65gg== X-Gm-Message-State: AOAM532kevsSOrH2CUzoN7VFAJactTMkRAugsBv17yX55BWrzzU205eh eLKtKO/Cb2LRxd0Qa4jwjhzS+Q== X-Received: by 2002:a63:6f4c:: with SMTP id k73mr21295263pgc.61.1635764382391; Mon, 01 Nov 2021 03:59:42 -0700 (PDT) Received: from leoy-ThinkPad-X240s ([103.136.124.227]) by smtp.gmail.com with ESMTPSA id h18sm16015568pfh.144.2021.11.01.03.59.38 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 01 Nov 2021 03:59:41 -0700 (PDT) Date: Mon, 1 Nov 2021 18:59:36 +0800 From: Leo Yan To: Suzuki K Poulose Cc: Mathieu Poirier , Mike Leach , Alexander Shishkin , James Clark , coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v1 1/4] coresight: etm4x: Add lock for reading virtual context ID comparator Message-ID: <20211101105936.GA352474@leoy-ThinkPad-X240s> References: <20211031144214.237879-1-leo.yan@linaro.org> <20211031144214.237879-2-leo.yan@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Suzuki, On Mon, Nov 01, 2021 at 09:49:06AM +0000, Suzuki Kuruppassery Poulose wrote: > Hi Leo > > On 31/10/2021 14:42, Leo Yan wrote: > > When read the virtual context ID comparator value via sysfs node, the > > driver firstly reads out the index, then reads the comparator value > > based on index. > > > This patch adds the spinlock to protect the atomicity for up two steps. > > minor nit: This could be : > > "Updates to the values and the index are protected via the > spinlock. Ensure we use the same lock to read the value > safely" Yeah, this is more simple and clear. Will use it. > With that: > > Reviewed-by: Suzuki K Poulose Thanks for review. Leo