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 1817DC678D5 for ; Tue, 7 Mar 2023 10:33:40 +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-Transfer-Encoding:Content-Type: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=KbTiIHPlBx7qijv9/DNkBxwoPYsrXtGHpeWJOsvO+Ec=; b=kSfibLLgs4C657 47vu650QGt4gIIUsMPZ6NWV8SS7dgLftRmpGnVBTIXz8r/BtRJtfaXMpnCmajYa0YOz4L9f3SWDOy rKZvbEP5M9abZKkVN0xoJHG1y+rU02oxhzTotPHsqLjRb+eZpoAsaAmV2bHI1XW9+cpycw2YfFT5B 0X8FTHVyalIZqIu6HROzg51F42dsfpehffxuneyONadqyYHDurvpY95ln+CfNaIkCLtLbnttd/S+4 uxFy8Q2K4a79yQOtEDp9B0ZyQgxseBm6an2oz3WCUF/E58y7cTcXNOv/1LNmv+q/8eRY5q+MCnk3J +hkfyI4GJFk/h17r1oWQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1pZUcn-00HIoa-VH; Tue, 07 Mar 2023 10:32:54 +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 1pZUcj-00HImZ-5c for linux-arm-kernel@lists.infradead.org; Tue, 07 Mar 2023 10:32:50 +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 0956B113E; Tue, 7 Mar 2023 02:33:30 -0800 (PST) Received: from [192.168.1.3] (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 090593F71A; Tue, 7 Mar 2023 02:32:44 -0800 (PST) Message-ID: <8ca2b07e-674e-afb6-ff12-87504f51f252@arm.com> Date: Tue, 7 Mar 2023 10:32:33 +0000 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.7.1 Subject: Re: [BUG] perf: No samples found when using kcore + coresight To: Yang Shi Cc: linux-perf-users@vger.kernel.org, LAK , coresight@lists.linaro.org, Linux Kernel Mailing List , leo.yan@linaro.org, mathieu.poirier@linaro.org, adrian.hunter@intel.com, Jiri Olsa , acme@redhat.com, mike.leach@linaro.org, Will Deacon , suzuki.poulose@arm.com References: Content-Language: en-US From: James Clark In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230307_023249_293784_664153FC X-CRM114-Status: GOOD ( 17.24 ) 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-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 06/03/2023 21:13, Yang Shi wrote: > Hi, > > I'm seeking some help regarding perf record --kcore + coresight. When > I tracing with perf record --kcore -e cs_etm ... , perf report shows > "The perf.data/data data has no samples!". > > I tried other combinations: > 1. perf record --kcore (w/o using coresight): works > 2. perf record -e cs_etm ... : works > 3. Manually copy kcore with perf buildid-cache, then run perf record > -e cs_etm... : works > > So just "perf record --kcore -e cs_etm ..." doesn't work. > > I'm using v6.2 kernel and the perf is built from the same kernel > source with OpenCSD 1.4. Also attached the sample file generated by > perf. > > Any suggestion is appreciated. > > Thanks, > Yang Hi Yang, I don't see any issue with this command and I still get samples: perf record -e cs_etm// --kcore -- true You might want to try running both record and report in verbose and stdio mode (-vvv --stdio) to see if you see any warnings. I can't think of any way --kcore would cause an issue because all it does is save kcore into the .debug cache rather than affecting the actual perf.data file. Are you running perf report in the same place the recording was made? Or on another system? James _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel