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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 CE2CDC2D0EC for ; Fri, 27 Mar 2020 14:56:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AE61D20774 for ; Fri, 27 Mar 2020 14:56:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727652AbgC0O4O convert rfc822-to-8bit (ORCPT ); Fri, 27 Mar 2020 10:56:14 -0400 Received: from eu-smtp-delivery-151.mimecast.com ([207.82.80.151]:49056 "EHLO eu-smtp-delivery-151.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726515AbgC0O4O (ORCPT ); Fri, 27 Mar 2020 10:56:14 -0400 Received: from AcuMS.aculab.com (156.67.243.126 [156.67.243.126]) (Using TLS) by relay.mimecast.com with ESMTP id uk-mta-170-SGnCHWRUOGKntCL40nF8vw-1; Fri, 27 Mar 2020 14:56:09 +0000 X-MC-Unique: SGnCHWRUOGKntCL40nF8vw-1 Received: from AcuMS.Aculab.com (fd9f:af1c:a25b:0:43c:695e:880f:8750) by AcuMS.aculab.com (fd9f:af1c:a25b:0:43c:695e:880f:8750) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Fri, 27 Mar 2020 14:56:08 +0000 Received: from AcuMS.Aculab.com ([fe80::43c:695e:880f:8750]) by AcuMS.aculab.com ([fe80::43c:695e:880f:8750%12]) with mapi id 15.00.1347.000; Fri, 27 Mar 2020 14:56:08 +0000 From: David Laight To: 'Steven Rostedt' CC: "linux-kernel@vger.kernel.org" , Ingo Molnar , Andrew Morton , Peter Zijlstra , Masami Hiramatsu , "Alexei Starovoitov" , Peter Wu , Jonathan Corbet , Tom Zanussi , "Shuah Khan" , bpf Subject: RE: [PATCH 00/12 v2] ring-buffer/tracing: Remove disabling of ring buffer while reading trace file Thread-Topic: [PATCH 00/12 v2] ring-buffer/tracing: Remove disabling of ring buffer while reading trace file Thread-Index: AQHV/kYCQIwPxRMFlk+UdEERk+KYoKhTa8kQgAhKroCAAIuIsIAAShAAgAAFRhA= Date: Fri, 27 Mar 2020 14:56:08 +0000 Message-ID: References: <20200319232219.446480829@goodmis.org> <2a7f96545945457cade216aa3c736bcc@AcuMS.aculab.com> <20200326214617.697634f3@oasis.local.home> <60977a309b5d46979a9a9bbd46c10932@AcuMS.aculab.com> <20200327103046.08f06131@gandalf.local.home> In-Reply-To: <20200327103046.08f06131@gandalf.local.home> Accept-Language: en-GB, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.202.205.107] MIME-Version: 1.0 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: aculab.com Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Steven Rostedt > Sent: 27 March 2020 14:31 .. > > Along with the one that lets you read the raw trace and get EOF. > > Can you explain this more? I think we talked about this before, but I don't > remember the details. I was trying to use schedviz (on github from google). It reads out the raw trace (for some scheduler events) and then postprocesses it to generate to nice pictures. However the shell script it uses for the captures has to run the copies in the background, sleep a random time, and then kill all the copies having hoped it has waited long enough - truly horrid. There is also some confusion (IIRC between a header and your library code) about the 'time-delta' on 'pad' entries. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)