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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 9F5ABC433E0 for ; Thu, 4 Feb 2021 04:03:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4E2E564DA5 for ; Thu, 4 Feb 2021 04:03:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232060AbhBDECS (ORCPT ); Wed, 3 Feb 2021 23:02:18 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60846 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231475AbhBDEBT (ORCPT ); Wed, 3 Feb 2021 23:01:19 -0500 Received: from mail-pg1-x533.google.com (mail-pg1-x533.google.com [IPv6:2607:f8b0:4864:20::533]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2AF33C0613ED for ; Wed, 3 Feb 2021 20:00:39 -0800 (PST) Received: by mail-pg1-x533.google.com with SMTP id o16so1220093pgg.5 for ; Wed, 03 Feb 2021 20:00:39 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=ekev10vmev54YC6YS3oAAP96uS/rpxiv7X/ntZD7Dbw=; b=mGAZTDHihq/drbQSw1FvQ3M47w93qk6ssTjsPvKjn/8OypobWipJHgGbENvZxoXk7E VoQ9Yxi8h8KPwXTc0xJO5qlhUe07suXBeeqja5pC/p+M1YxItxxTkNnkt+Gev9wz5mz7 yfA3MX3TZPg5cUv7fZxHMcl58+oPZjWdWka9tZohkswIxTaVTPGZtEZrRQS8pxL9mume tHt2PcrEt1MjpOMWttkQ2aYUjEFv9muE/mO5fWssXE4E36FYO5SDRIoMENzBVL6Hx0f5 b6c2N8allH6eGElknLNli2mJlB2KE7CTL4QS7rotnjB3MkBNWHjpOgsuj/zQmPn81iUf +Wvg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=ekev10vmev54YC6YS3oAAP96uS/rpxiv7X/ntZD7Dbw=; b=HdLSdZAUscCxg7GZGBcvoJFVeGOZ3U7Vn+D5NNPZ/CwDv1dt9QNJGSAhOXSsoQZ7Gt kx/ztBM52hCJd/5l2A8Pe1p0H5lOS8KP3E4Jp4So6wnRhtfa/RDrzjIjpGjwVC9CBtlT TshuIOvHKbUCwe120yCUppNSp+xqdwjxwpnSN1/1enQ2t/J+5seLZj2h2ZdfdTFgIdPJ MtDrZYHSYvkQ6kblbSxTpAMOXS63UTb3ZETvJXdULGXGZsgy+Pg3EdAd+iEcPGEuSOos D+oH1FYUlQ7JbCDLsMbxwGsierw5daVv+6f0HOwZGlCVg/McaHmEoBdgVciOuzhPR+c3 9NLA== X-Gm-Message-State: AOAM532JfjngIgRfVwpKE82DNqd93pwST4s/rRs/X9UPX7NrPFegSfD5 HKIFTdqontfNTnMR7++zS5ntLg== X-Google-Smtp-Source: ABdhPJxm7gZSrWcznAoy/XnaxZqv9Jlv4v0jt9MlTHa9aQZbfi7VCAe+wh3ZDfVyF6iZDhLn0MQIYQ== X-Received: by 2002:a63:f703:: with SMTP id x3mr6871446pgh.66.1612411238656; Wed, 03 Feb 2021 20:00:38 -0800 (PST) Received: from leoy-ThinkPad-X240s ([202.155.204.36]) by smtp.gmail.com with ESMTPSA id 124sm3769128pfd.59.2021.02.03.20.00.30 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 03 Feb 2021 20:00:38 -0800 (PST) Date: Thu, 4 Feb 2021 12:00:28 +0800 From: Leo Yan To: Suzuki K Poulose Cc: Arnaldo Carvalho de Melo , Mathieu Poirier , Mike Leach , Jonathan Corbet , Alexander Shishkin , John Garry , Will Deacon , Peter Zijlstra , Ingo Molnar , Mark Rutland , Jiri Olsa , Namhyung Kim , Daniel Kiss , Denis Nikitin , coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, Al Grant Subject: Re: [PATCH v2 6/7] perf cs-etm: Detect pid in VMID for kernel running at EL2 Message-ID: <20210204040021.GF11059@leoy-ThinkPad-X240s> References: <20210202163842.134734-1-leo.yan@linaro.org> <20210202163842.134734-7-leo.yan@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org On Tue, Feb 02, 2021 at 11:29:47PM +0000, Suzuki Kuruppassery Poulose wrote: > On 2/2/21 4:38 PM, Leo Yan wrote: > > From: Suzuki K Poulose > > > > The PID of the task could be traced as VMID when the kernel is running > > at EL2. Teach the decoder to look for VMID when the CONTEXTIDR (Arm32) > > or CONTEXTIDR_EL1 (Arm64) is invalid but we have a valid VMID. > > > > Cc: Mike Leach > > Cc: Mathieu Poirier > > Cc: Al Grant > > Co-developed-by: Leo Yan > > Signed-off-by: Suzuki K Poulose > > Signed-off-by: Leo Yan > > --- > > .../perf/util/cs-etm-decoder/cs-etm-decoder.c | 32 ++++++++++++++++--- > > 1 file changed, 28 insertions(+), 4 deletions(-) > > > > diff --git a/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c b/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c > > index 3f4bc4050477..fb2a163ff74e 100644 > > --- a/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c > > +++ b/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c > > @@ -6,6 +6,7 @@ > > * Author: Mathieu Poirier > > */ > > +#include > > #include > > #include > > #include > > @@ -491,13 +492,36 @@ cs_etm_decoder__set_tid(struct cs_etm_queue *etmq, > > const ocsd_generic_trace_elem *elem, > > const uint8_t trace_chan_id) > > { > > - pid_t tid; > > + pid_t tid = -1; > > + u64 pid_fmt; > > + int ret; > > - /* Ignore PE_CONTEXT packets that don't have a valid contextID */ > > - if (!elem->context.ctxt_id_valid) > > + ret = cs_etm__get_pid_fmt(trace_chan_id, &pid_fmt); > > + if (ret) > > Is this something we can cache in this function ? e.g, > static u64 pid_fmt; > > if (!pid_pfmt) > ret = cs_etm__get_pid_fmt(trace_chan_id, &pid_fmt); > > As all the ETMs will be running at the same exception level. Sorry that I let you repeated your comments again. To be honest, I considered this after read your comment in the previous series, but I thought it's possible that multiple CPUs have different PID format, especially for big.LITTLE arch. After read your suggestion again, I think my concern is not valid, even for big.LITTLE, all CPUs should run on the same kernel exception level. So will follow up your suggestion to cache "pid_fmt". > > > + return OCSD_RESP_FATAL_SYS_ERR; > > + > > + /* > > + * Process the PE_CONTEXT packets if we have a valid contextID or VMID. > > + * If the kernel is running at EL2, the PID is traced in CONTEXTIDR_EL2 > > + * as VMID, Bit ETM_OPT_CTXTID2 is set in this case. > > + */ > > + switch (pid_fmt) { > > + case BIT(ETM_OPT_CTXTID): > > + if (elem->context.ctxt_id_valid) > > + tid = elem->context.context_id; > > + break; > > + case BIT(ETM_OPT_CTXTID2) | BIT(ETM_OPT_CTXTID): > > I would rather fix the cs_etm__get_pid_fmt() to return either of these > as commented. i.e, ETM_OPT_CTXTID or ETM_OPT_CTXTID2. Thus we don't > need the this case. I explained why I set both bits for ETM_OPT_CTXTID and ETM_OPT_CTXTID2 in the patch 05/07. Could you take a look for it? > With the above two addressed: > > Reviewed-by: Suzuki K Poulose Thanks, Leo