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=-8.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT 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 D2D9CC65BAE for ; Thu, 13 Dec 2018 12:38:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9657520879 for ; Thu, 13 Dec 2018 12:38:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1544704739; bh=6/+wVR+4FeLl7Gmd1usmDwcc0CvYvxL9d0LTHNtuQ4U=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=hKPO+zCXj71/hbrHnh5qBBuz/vJQ8iyexe5q7vl/f6sCxGJYjMEhoDz1d1GlL7VKn lxARH6jJIExObboxNi+0RUDh3cl0/aFGIpE61AlzS1i7rPkH967p4PU0i1ACMHbd02 31vukdtZuI6GSyxU3OiHuTEBi6PJWwdOiue6RF6U= DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9657520879 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org 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 S1729188AbeLMMi6 (ORCPT ); Thu, 13 Dec 2018 07:38:58 -0500 Received: from mail.kernel.org ([198.145.29.99]:55912 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729059AbeLMMi6 (ORCPT ); Thu, 13 Dec 2018 07:38:58 -0500 Received: from quaco.ghostprotocols.net (unknown [190.15.121.82]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B2DEB2086D; Thu, 13 Dec 2018 12:38:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1544704736; bh=6/+wVR+4FeLl7Gmd1usmDwcc0CvYvxL9d0LTHNtuQ4U=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=VybyT44FeVWNR0QeRCSSpMCzZK/7fuPzoJbikQsishe6iSaozdQlm7W0lqJCXIbCZ z4bDBCCBFk17PvNZGxr1+rRUkku5XFeVwN0l+E8RC8fwOj1lCIL+MPWNfCCM6GD34a kX1DTjp/JbwBSSLfx+7nCejqnZZxqvAzOUyPha04= Received: by quaco.ghostprotocols.net (Postfix, from userid 1000) id 7AA2241B1D; Thu, 13 Dec 2018 09:38:54 -0300 (-03) Date: Thu, 13 Dec 2018 09:38:54 -0300 From: Arnaldo Carvalho de Melo To: Leo Yan Cc: Mathieu Poirier , Alexander Shishkin , Jiri Olsa , Namhyung Kim , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Coresight ML , Mike Leach , Robert Walker Subject: Re: [PATCH v3 6/8] perf cs-etm: Treat NO_SYNC element as trace discontinuity Message-ID: <20181213123854.GE21027@kernel.org> References: <1544513908-16805-1-git-send-email-leo.yan@linaro.org> <1544513908-16805-7-git-send-email-leo.yan@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1544513908-16805-7-git-send-email-leo.yan@linaro.org> X-Url: http://acmel.wordpress.com User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Em Tue, Dec 11, 2018 at 03:38:26PM +0800, Leo Yan escreveu: > CoreSight tracer driver might insert barrier packet between different > buffers, thus the decoder can spot the boundaries based on the barrier > packet; the decoder is possible to hit a barrier packet and emit a > NO_SYNC element, then the decoder will find a periodic synchronisation > point inside that next trace block that starts trace again but does not > have the TRACE_ON element as indicator - usually because this block of > trace has wrapped the buffer so we have lost the original point that > trace was enabled. > > In upper case, it results in the trace stream only inserts the > OCSD_GEN_TRC_ELEM_NO_SYNC element in the middle of tracing stream, but > we don't handle NO_SYNC element properly and at the end users miss to > see the info for trace discontinuity. "In upper case"? Maybe: In the former case it causes the insertion of a OCSD_GEN_TRC_ELEM_NO_SYNC in the middle of the the tracing stream, but as we were npt handling the NO_SYNC element properly which ends up making users miss the discontinuity indication"? > Though OCSD_GEN_TRC_ELEM_NO_SYNC is different from CS_ETM_TRACE_ON when > output from the decoder, but both of them indicate the trace data is can we remove the "but" and "of them" (redundant) above? > discontinuous; this patch treats OCSD_GEN_TRC_ELEM_NO_SYNC as trace a > discontinuity and generates CS_ETM_DISCONTINUITY packet for it, so > cs-etm can handle discontinuity for this case, finally it saves the last it (way too many "discontinuity") > trace data for previous trace block and restart samples for new block. > > Signed-off-by: Leo Yan > Reviewed-by: Mathieu Poirier > Cc: Mike Leach > Cc: Robert Walker > --- > tools/perf/util/cs-etm-decoder/cs-etm-decoder.c | 1 - > 1 file changed, 1 deletion(-) > > 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 1039f364..bee026e 100644 > --- a/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c > +++ b/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c > @@ -410,7 +410,6 @@ static ocsd_datapath_resp_t cs_etm_decoder__gen_trace_elem_printer( > case OCSD_GEN_TRC_ELEM_UNKNOWN: > break; > case OCSD_GEN_TRC_ELEM_NO_SYNC: > - break; > case OCSD_GEN_TRC_ELEM_TRACE_ON: > resp = cs_etm_decoder__buffer_discontinuity(decoder, > trace_chan_id); > -- > 2.7.4 -- - Arnaldo