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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 36C75C433FE for ; Wed, 9 Feb 2022 05:48:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Content-Type: Content-Transfer-Encoding:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:From:References:To:Subject:MIME-Version: Date:Message-ID:Reply-To:Cc:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=HMSNXiz0avP5bz2B1gxfPN4j5IgJsDfkOAGqHCYlZGw=; b=BuUrIGdXWabU1+pZHJUw8T1fTy yD3kqj70acbQZgnkuo+VgJKPzASvd04pZtuwFuzNjPE+FK0h4H6LIj1xejZU8KShXux8Kx+AAldic PYkKgCipu2Lpadtcn/ZHXb0mDs1i/JfgEZz0IBfvNXDGMAD+s5MSGCZemmVE72JiBJPczyxkPXNh2 kqpYA5wyrDHW3DZaistBtOEGEUGyeBNNmYL6Fe9HVJw4eL06yM1xpqO1xoKQWK+XzMo8bYpt/YC9U EKKdNMZzs/2TKv95hKPI1Myeb4lqPCK4TDKx76fKltJWEkNAHOHyZkp4fuCnRmIfU4JdVN9Bglkp+ NARrnFHA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nHfpG-00GHfk-5S; Wed, 09 Feb 2022 05:47:34 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nHfpC-00GHfO-DX for linux-arm-kernel@lists.infradead.org; Wed, 09 Feb 2022 05:47:31 +0000 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 8E5F5ED1; Tue, 8 Feb 2022 21:47:28 -0800 (PST) Received: from [10.57.88.245] (unknown [10.57.88.245]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id DE3133F718; Tue, 8 Feb 2022 21:47:26 -0800 (PST) Message-ID: <6b91293a-1149-2c77-04a4-421a45d4e1e0@arm.com> Date: Wed, 9 Feb 2022 05:47:24 +0000 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:91.0) Gecko/20100101 Thunderbird/91.5.1 Subject: Re: [PATCH v2 RESEND 1/4] coresight: etm4x: Add lock for reading virtual context ID comparator To: Leo Yan , Mathieu Poirier , Mike Leach , Alexander Shishkin , coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org References: <20220204152403.71775-1-leo.yan@linaro.org> <20220204152403.71775-2-leo.yan@linaro.org> From: Suzuki K Poulose In-Reply-To: <20220204152403.71775-2-leo.yan@linaro.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220208_214730_539091_A0D9B7A5 X-CRM114-Status: GOOD ( 14.28 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Leo On 04/02/2022 15:24, Leo Yan wrote: > Updates to the values and the index are protected via the spinlock. > Ensure we use the same lock to read the value safely. > > Signed-off-by: Leo Yan > Reviewed-by: Suzuki K Poulose > --- > drivers/hwtracing/coresight/coresight-etm4x-sysfs.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c b/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c > index 10ef2a29006e..2f3b4eef8261 100644 > --- a/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c > +++ b/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c > @@ -2111,7 +2111,9 @@ static ssize_t vmid_val_show(struct device *dev, > struct etmv4_drvdata *drvdata = dev_get_drvdata(dev->parent); > struct etmv4_config *config = &drvdata->config; > > + spin_lock(&drvdata->spinlock); > val = (unsigned long)config->vmid_val[config->vmid_idx]; > + spin_unlock(&drvdata->spinlock); > return scnprintf(buf, PAGE_SIZE, "%#lx\n", val); > } > I have queued this patch. For the rest, we would need to wait until the helper lands in the rc. Suzuki _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel