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=-5.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no 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 E6EB6C388F7 for ; Fri, 13 Nov 2020 09:49:10 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 00B4A20936 for ; Fri, 13 Nov 2020 09:49:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="czR5ZUPS" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 00B4A20936 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Type: Content-Transfer-Encoding:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date:Message-ID:From: References:To:Subject:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=jE0ViWxLPPF25MBir4mwFxIWCstdAYcpXddn/M5lG/Q=; b=czR5ZUPS5HaJI8FPoKPJKQlun owPSp7Ki6yXJBc1QuX82xkePyfkPXMlIhlitOKM+n5gGyDkXN6wCY7n/AbSPeVrQptBcvW+4SFaTZ RSsmpffGEhC/OQUsP2Y9CJPQKtyUChpeIb2ikCYLOB/v6Chxq0CGIL2ei+Cb63uVXO2PxYET4tvrd 6iRQBZQp9jMo7HKJdsY+UapwbyOW+7kasC74P3bBy5rFctbU0mfhlgdj606+TZ42+c2fYgjbIbHjG dPX9djo44rTIRFgBTlD4TkmVllEN1JjjRNr0AyGz2QubYnsBb0LEa6ou411UdYmMIRHOK017rUeSV PNwz6k9kQ==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kdVgR-0006XA-Bk; Fri, 13 Nov 2020 09:47:55 +0000 Received: from foss.arm.com ([217.140.110.172]) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kdVgO-0006W4-C8 for linux-arm-kernel@lists.infradead.org; Fri, 13 Nov 2020 09:47:53 +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 0A5C314BF; Fri, 13 Nov 2020 01:47:51 -0800 (PST) Received: from [10.57.23.123] (unknown [10.57.23.123]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 70E613F6CF; Fri, 13 Nov 2020 01:47:49 -0800 (PST) Subject: Re: [PATCH 3/3] rfc: perf: cs_etm: Detect pid in VMID for kernel running at EL2 To: Leo Yan References: <20201110183313.1823760-1-suzuki.poulose@arm.com> <20201110183313.1823760-4-suzuki.poulose@arm.com> <20201113001105.GA22708@leoy-ThinkPad-X240s> From: Suzuki K Poulose Message-ID: <7e45fd42-0869-cd4f-1eaf-5d48e4464482@arm.com> Date: Fri, 13 Nov 2020 09:47:42 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.4.1 MIME-Version: 1.0 In-Reply-To: <20201113001105.GA22708@leoy-ThinkPad-X240s> Content-Language: en-GB X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201113_044752_502862_D2A2BC3B X-CRM114-Status: GOOD ( 23.06 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Al Grant , "mathieu.poirier@linaro.org" , Anshuman Khandual , "coresight@lists.linaro.org" , "linux-arm-kernel@lists.infradead.org" , "mike.leach@linaro.org" 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 11/13/20 12:11 AM, Leo Yan wrote: > On Wed, Nov 11, 2020 at 11:40:03AM +0000, Suzuki Kuruppassery Poulose wrote: >> On 11/11/20 11:03 AM, Al Grant wrote: > > [...] > >>> But if you must do it heuristically at decode time based on what >>> you see in packets, then it would be safer to say that if you see both >>> VMID and CONTEXIDR, the TID will be in VMID. >> >> This may not be entirely correct, unless we correlate the VMID_OPT. Because, >> when we add Virtualization support (vmid == actual vmid). >> >> So we should do: >> if (VMID && VMIDOPT) { >> tid = pid; >> } else if (CID) { >> >> } > > Rather than heuristic method, I think we can use metadata to store > "pid" entry in the function cs_etm_get_metadata(), so that in the > record phase, the "pid" is stored into perf data file. True, that is a good idea. That makes it future proof. > > When decode the trace data, we can retrieve "pid" value from the > metadata, and can base on the "pid" value to make decision for using > context_id or VMID. > > The metadata can be accessed by referring > cs_etm_queue::cs_etm_auxtrace::metadata; but the file > util/cs-etm-decoder/cs-etm-decoder.c cannot directly access the > metadata structure due to "cs_etm_queue" and "cs_etm_auxtrace" both > are defined in util/cs-etm.c. It's better to introduce a helper > function in util/cs-etm.c to retrieve "pid" value, like: > > u64 cs_etm__etmq_get_pid_type(struct cs_etm_queue *etmq); I am not an expert in that side, how it interacts with the OpenCSD. thus left this patch as an RFC. I appreciate your feedback and thoughts. If you feel like you could cleanup and implement this, please feel free to do so. Otherwise, I might try it out whenever I have some spare cycles to understand this side of the code (and this might be delayed). Cheers Suzuki > > Thanks, > Leo > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel