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=-9.2 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_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 2E009C43387 for ; Tue, 18 Dec 2018 22:10:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F0103218AD for ; Tue, 18 Dec 2018 22:10:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1545171054; bh=cV+EWGCRKnKm1DJ1KLIkyVctuTBV9Z0WKj287fkcmBs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=DF+M+elcnQP8mz6fiqjmW8eZzwCumWDPQudTRN+G1u141FWGE+dVh772we6/Wn6ws 9KuxXT/2eWYfuYb2jInd6icYpk+kkVQxHw5PCTYkVIgHFqpoyCVYX+kKM2O5470WvI UGeDhSN1L7xUiOw/Ic3JhlmUnwEQTLYRw+pZHdoI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728076AbeLRWKx (ORCPT ); Tue, 18 Dec 2018 17:10:53 -0500 Received: from mail.kernel.org ([198.145.29.99]:39528 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726802AbeLRWKv (ORCPT ); Tue, 18 Dec 2018 17:10:51 -0500 Received: from quaco.ghostprotocols.net (unknown [189.40.101.1]) (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 1EC28217D9; Tue, 18 Dec 2018 22:10:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1545171051; bh=cV+EWGCRKnKm1DJ1KLIkyVctuTBV9Z0WKj287fkcmBs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PdwzuoghBI4wfKX/C0uq8Uekn/FGzX03KX9zup9NgNq1dHXmToQE3cqVs1xuQcNm9 zuBfYowSkxCc0Ptkpx8JzbDVz+ECwr+HVqOUVDQ8VXBp2RA1ygqFN4y++HrQ6b7VN+ trDBxxzs+b0FhXO4rwCj0Rx6as938zmKaax0WlmQ= From: Arnaldo Carvalho de Melo To: Ingo Molnar Cc: Clark Williams , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Leo Yan , Alexander Shishkin , Jiri Olsa , Mike Leach , Namhyung Kim , Robert Walker , coresight ml , linux-arm-kernel@lists.infradead.org, Arnaldo Carvalho de Melo Subject: [PATCH 31/63] perf cs-etm: Treat NO_SYNC element as trace discontinuity Date: Tue, 18 Dec 2018 19:07:01 -0300 Message-Id: <20181218220733.15839-32-acme@kernel.org> X-Mailer: git-send-email 2.19.2 In-Reply-To: <20181218220733.15839-1-acme@kernel.org> References: <20181218220733.15839-1-acme@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Leo Yan The CoreSight tracer driver might insert barrier packets between different buffers, thus the decoder can spot the boundaries based on the barrier packet; it is possible for the decoder 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 the trace again but does not have the TRACE_ON element as indicator - usually because this trace block has wrapped the buffer so we have lost the original point when the trace was enabled. In the first case it causes the insertion of a OCSD_GEN_TRC_ELEM_NO_SYNC in the middle of the tracing stream, but as we were not handling the NO_SYNC element properly this ends up making users miss the discontinuity indications. Though OCSD_GEN_TRC_ELEM_NO_SYNC is different from CS_ETM_TRACE_ON when output from the decoder, both indicate that the trace data is discontinuous; this patch treats OCSD_GEN_TRC_ELEM_NO_SYNC as a trace discontinuity and generates a CS_ETM_DISCONTINUITY packet for it, so cs-etm can handle the discontinuity for this case, finally it saves the last trace data for the previous trace block and restart samples for the new block. Signed-off-by: Leo Yan Reviewed-by: Mathieu Poirier Cc: Alexander Shishkin Cc: Jiri Olsa Cc: Mike Leach Cc: Namhyung Kim Cc: Robert Walker Cc: coresight ml Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/1544513908-16805-7-git-send-email-leo.yan@linaro.org Signed-off-by: Arnaldo Carvalho de Melo --- 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 1039f364f4cc..bee026e76a4c 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); -- 2.19.2