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=-4.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_PASS,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 A13BFC43441 for ; Wed, 21 Nov 2018 13:12:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5C474214DA for ; Wed, 21 Nov 2018 13:12:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="bSCgqKVe" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5C474214DA 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 S1730879AbeKUXqT (ORCPT ); Wed, 21 Nov 2018 18:46:19 -0500 Received: from mail.kernel.org ([198.145.29.99]:60206 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726016AbeKUXqT (ORCPT ); Wed, 21 Nov 2018 18:46:19 -0500 Received: from jouet.infradead.org (unknown [179.97.41.186]) (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 0B0D1214C4; Wed, 21 Nov 2018 13:11:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1542805919; bh=pS5mD4w6EZEqbXDWqED6dE2MsKpQIlvbd5aV0iv8bdg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=bSCgqKVeF6coAm9EG5jrsO1pxB/B8q20xRIjPSh/3IvgjALl1OmRIE/YChWDQPDmC Zyl2y+oLufCAiaTQiF5fCNYCjBe0h9YVW+wyYCxLxpytW7IfnytJ86jf8y9p/U+OKq ksGOPOalttNw8nDCk6vJ4tI7xQYhnECABY27svzg= Received: by jouet.infradead.org (Postfix, from userid 1000) id 033501443D6; Wed, 21 Nov 2018 10:11:56 -0300 (-03) Date: Wed, 21 Nov 2018 10:11:56 -0300 From: Arnaldo Carvalho de Melo To: Wang Nan Cc: Song Liu , lkml , Jiri Olsa , Peter Zijlstra , Kernel Team Subject: Re: perf tools: remove option --tail-synthesize ? Message-ID: <20181121131156.GG6248@kernel.org> References: <89AC26A9-5A18-4608-8889-9C3C9C1C69D3@fb.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <89AC26A9-5A18-4608-8889-9C3C9C1C69D3@fb.com> X-Url: http://acmel.wordpress.com User-Agent: Mutt/1.9.2 (2017-12-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Em Wed, Nov 21, 2018 at 07:45:28AM +0000, Song Liu escreveu: > Hi, > > I found perf-record --tail-synthesize without --overwrite breaks symbols > for perf-script, perf-report, etc. For example: > > [root@]# ~/perf record -ag --tail-synthesize -- sleep 1 > [ perf record: Woken up 1 times to write data ] > [ perf record: Captured and wrote 1.129 MB perf.data (3531 samples) ] > [root@]# ~/perf script | head > swapper 0 [000] 1250675.051971: 1 cycles:ppp: > ffffffff81009e15 [unknown] ([unknown]) > ffffffff81196b19 [unknown] ([unknown]) > ffffffff81196579 [unknown] ([unknown]) > ffffffff81110ca7 [unknown] ([unknown]) > ffffffff81a01f4a [unknown] ([unknown]) > ffffffff81a017bf [unknown] ([unknown]) > ffffffff8180e17a [unknown] ([unknown]) > > perf-record with --overwrite does NOT have this issue. > > After digging into this, I found this issue is introduced by commit > a73e24d240bc136619d382b1268f34d75c9d25ce. > > Reverting this commit does fix this issue. However, on a second thought, > I feel it is probably better just drop --tail-synthesize, as it doesn't > make much sense without --overwrite. All we need is to do tail_synthesize > when --overwrite is set. > > Thoughts? Wang, wdyt? - Arnaldo