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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id B7BC5C433EF for ; Sun, 15 May 2022 22:06:46 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 2BF996B0073; Sun, 15 May 2022 18:06:46 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 26F126B0075; Sun, 15 May 2022 18:06:46 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 15EE56B0078; Sun, 15 May 2022 18:06:46 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 07E106B0073 for ; Sun, 15 May 2022 18:06:46 -0400 (EDT) Received: from smtpin04.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay13.hostedemail.com (Postfix) with ESMTP id D041F60D7B for ; Sun, 15 May 2022 22:06:45 +0000 (UTC) X-FDA: 79469362770.04.BDB39CD Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf30.hostedemail.com (Postfix) with ESMTP id C1E0180007 for ; Sun, 15 May 2022 22:06:23 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 35F2E61160; Sun, 15 May 2022 22:06:44 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0803EC385B8; Sun, 15 May 2022 22:06:41 +0000 (UTC) Date: Sun, 15 May 2022 18:06:40 -0400 From: Steven Rostedt To: Roman Gushchin Cc: Vasily Averin , Shakeel Butt , Ingo Molnar , kernel@openvz.org, linux-kernel@vger.kernel.org, Vlastimil Babka , Michal Hocko , cgroups@vger.kernel.org, Andrew Morton , Dennis Zhou , Tejun Heo , Christoph Lameter , linux-mm@kvack.org, "linux-trace-users@vger.kernel.org" Subject: Re: [PATCH v2] percpu: improve percpu_alloc_percpu event trace Message-ID: <20220515180640.0ae2ead5@gandalf.local.home> In-Reply-To: References: <2b388d09-940e-990f-1f8a-2fdaa9210fa0@openvz.org> X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Authentication-Results: imf30.hostedemail.com; dkim=none; spf=pass (imf30.hostedemail.com: domain of "SRS0=XP9Z=VX=goodmis.org=rostedt@kernel.org" designates 139.178.84.217 as permitted sender) smtp.mailfrom="SRS0=XP9Z=VX=goodmis.org=rostedt@kernel.org"; dmarc=none X-Rspam-User: X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: C1E0180007 X-Stat-Signature: qyixqnsbs6rdk5qsig8ut3hef1phg6ag X-HE-Tag: 1652652383-293990 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, 10 May 2022 19:33:17 -0700 Roman Gushchin wrote: > --- a/include/trace/events/percpu.h > > +++ b/include/trace/events/percpu.h > > @@ -6,15 +6,20 @@ > > #define _TRACE_PERCPU_H > > > > #include > > +#include > > > > TRACE_EVENT(percpu_alloc_percpu, > > > > - TP_PROTO(bool reserved, bool is_atomic, size_t size, > > - size_t align, void *base_addr, int off, void __percpu *ptr), > > + TP_PROTO(unsigned long call_site, > > + bool reserved, bool is_atomic, size_t size, > > + size_t align, void *base_addr, int off, > > + void __percpu *ptr, size_t bytes_alloc, gfp_t gfp_flags), > > Don't we want to preserve the order and add the call_site at the end? > Trace events are not ABI, but if we don't have a strong reason to break it, > I'd preserve the old order. Ideally everyone should be using libtraceevent which will parse the format file for the needed entries. Nothing (important) should be parsing the raw ascii from the trace files. It's slow and unreliable. The raw format (trace_pipe_raw) files, along with libtraceevent will handle fining the fields you are looking for, even if the fields move around (internally or externally). Then there's trace-cruncher (a python script that uses libtracefs and libtraceevent) that will work too. https://github.com/vmware/trace-cruncher -- Steve