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 B5B09C433EF for ; Thu, 9 Dec 2021 11:02:14 +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:Cc:To:Subject: MIME-Version:Date:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=Drsgt8ze287dvBAut0jNi1r2umas+TtwK/krmxb0KVw=; b=yflYLvtr6NyThp KlCypkX8tu+PZEpgk/jq0ybO2UfdHVWfGSO5STvWZKoROCm8vRTfw0yk9l6Mg0jFcK2i0ZmVDMS/W 6SbBzo3EnGbKxRmoN0KUsqyKnaGQ9YiM+YPcKB6+TGZzQnBJgUiN7L1cP5J48WEQ6fNUv+qdFnkBi /O7a1VZuwzIRxj+5gto9c0IlXu162GP2S3udNNFgAk+oagpOiebWl3UMsq07+vBXajJn8Sgk9DaXw Eikfqa/DEMPwdIr3qKGdAZ4EGSxAE7MEav5I8U7mXVx9CgBzToaqJHJT+DJZrR7N5TPB9uL3/7lPB s2kxg2F6zHlyoLg/N4rw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mvHAQ-00FiJ0-S0; Thu, 09 Dec 2021 11:00:50 +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 1mvHAN-00FiGy-H8 for linux-arm-kernel@lists.infradead.org; Thu, 09 Dec 2021 11:00:49 +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 0DCD61FB; Thu, 9 Dec 2021 03:00:44 -0800 (PST) Received: from [10.57.82.128] (unknown [10.57.82.128]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id C30863F73B; Thu, 9 Dec 2021 03:00:41 -0800 (PST) Message-ID: Date: Thu, 9 Dec 2021 11:00:40 +0000 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:91.0) Gecko/20100101 Thunderbird/91.3.2 Subject: Re: [PATCH 2/3] coresight: Fail to open with return stacks if they are unavailable To: James Clark , mathieu.poirier@linaro.org, coresight@lists.linaro.org Cc: Mike Leach , Leo Yan , John Garry , Will Deacon , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org References: <20211208160907.749482-1-james.clark@arm.com> <20211208160907.749482-2-james.clark@arm.com> From: Suzuki K Poulose In-Reply-To: <20211208160907.749482-2-james.clark@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211209_030047_689721_48A50FDE X-CRM114-Status: GOOD ( 18.99 ) 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 On 08/12/2021 16:09, James Clark wrote: > Maintain consistency with the other options by failing to open when they > aren't supported. For example ETM_OPT_TS, ETM_OPT_CTXTID2 and the newly > added ETM_OPT_BRANCH_BROADCAST all return with -EINVAL if they are > requested but not supported by hardware. > > The consequence of not doing this is that the user may not be > aware that they are not enabling the feature as it is silently disabled. > > Signed-off-by: James Clark > --- > drivers/hwtracing/coresight/coresight-etm4x-core.c | 13 +++++++++---- > 1 file changed, 9 insertions(+), 4 deletions(-) > > diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c > index d2bafb50c66a..0a9bb943a5e5 100644 > --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c > +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c > @@ -674,10 +674,15 @@ static int etm4_parse_event_config(struct coresight_device *csdev, > } > > /* return stack - enable if selected and supported */ > - if ((attr->config & BIT(ETM_OPT_RETSTK)) && drvdata->retstack) > - /* bit[12], Return stack enable bit */ > - config->cfg |= BIT(12); > - > + if (attr->config & BIT(ETM_OPT_RETSTK)) { > + if (!drvdata->retstack) { > + ret = -EINVAL; > + goto out; > + } else { > + /* bit[12], Return stack enable bit */ > + config->cfg |= BIT(12); > + } nit: While at this, please could you change the hard coded value to ETM4_CFG_BIT_RETSTK ? Otherwise, looks good to me Suzuki _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel