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=-2.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 984DAECDFB3 for ; Tue, 17 Jul 2018 17:12:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 59FC320684 for ; Tue, 17 Jul 2018 17:12:18 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 59FC320684 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731251AbeGQRpw (ORCPT ); Tue, 17 Jul 2018 13:45:52 -0400 Received: from foss.arm.com ([217.140.101.70]:50152 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731215AbeGQRpw (ORCPT ); Tue, 17 Jul 2018 13:45:52 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id C59E51688; Tue, 17 Jul 2018 10:12:15 -0700 (PDT) Received: from en101.cambridge.arm.com (en101.cambridge.arm.com [10.1.206.73]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 6F0E03F5A0; Tue, 17 Jul 2018 10:12:14 -0700 (PDT) From: Suzuki K Poulose To: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org, robert.walker@arm.com, mathieu.poirier@linaro.org, mike.leach@linaro.org, coresight@lists.linaro.org, Suzuki K Poulose Subject: [PATCH v2 05/10] coresight: tmc-etr: Relax collection of trace from sysfs mode Date: Tue, 17 Jul 2018 18:11:36 +0100 Message-Id: <1531847501-22226-6-git-send-email-suzuki.poulose@arm.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1531847501-22226-1-git-send-email-suzuki.poulose@arm.com> References: <1531847501-22226-1-git-send-email-suzuki.poulose@arm.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Since the ETR now uses mode specific buffers, we can reliably provide the trace data captured in sysfs mode, even when the ETR is operating in PERF mode. Cc: Mathieu Poirier Signed-off-by: Suzuki K Poulose --- drivers/hwtracing/coresight/coresight-tmc-etr.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c index 58c7935..671a2ba 100644 --- a/drivers/hwtracing/coresight/coresight-tmc-etr.c +++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c @@ -1168,19 +1168,17 @@ int tmc_read_prepare_etr(struct tmc_drvdata *drvdata) goto out; } - /* Don't interfere if operated from Perf */ - if (drvdata->mode == CS_MODE_PERF) { - ret = -EINVAL; - goto out; - } - - /* If sysfs_buf is NULL the trace data has been read already */ + /* + * We can safely allow reads even if the ETR is operating in PERF mode, + * since the sysfs session is captured in mode specific data. + * If drvdata::sysfs_data is NULL the trace data has been read already. + */ if (!drvdata->sysfs_buf) { ret = -EINVAL; goto out; } - /* Disable the TMC if we are trying to read from a running session */ + /* Disable the TMC if we are trying to read from a running session. */ if (drvdata->mode == CS_MODE_SYSFS) tmc_etr_disable_hw(drvdata); -- 2.7.4