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=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_2 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 7CA3EC43460 for ; Tue, 4 May 2021 13:32:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 60104613CA for ; Tue, 4 May 2021 13:32:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231199AbhEDNdk (ORCPT ); Tue, 4 May 2021 09:33:40 -0400 Received: from mail.kernel.org ([198.145.29.99]:58808 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231175AbhEDNdk (ORCPT ); Tue, 4 May 2021 09:33:40 -0400 Received: from gandalf.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (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 03953610A7; Tue, 4 May 2021 13:32:44 +0000 (UTC) Date: Tue, 4 May 2021 09:32:43 -0400 From: Steven Rostedt To: Stefan Metzmacher Cc: Ingo Molnar , linux-trace-devel@vger.kernel.org, io-uring Subject: Re: Tracing busy processes/threads freezes/stalls the whole machine Message-ID: <20210504093243.4d664594@gandalf.local.home> In-Reply-To: References: <293cfb1d-8a53-21e1-83c1-cdb6e2f32c65@samba.org> <20210504092404.6b12aba4@gandalf.local.home> 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 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On Tue, 4 May 2021 15:28:12 +0200 Stefan Metzmacher wrote: > Am 04.05.21 um 15:24 schrieb Steven Rostedt: > > On Thu, 22 Apr 2021 16:26:57 +0200 > > Stefan Metzmacher wrote: > > > >> Hi Steven, hi Ingo, > >> > > > > Sorry, somehow I missed this. > > > >> # But > >> # trace-cmd record -e all -P 7 > > > > I'm curious. > > > > What is the clock set to? What does: > > > > # trace-cmd list -C > > > > show? > > On both machine (physical and VM): > trace-cmd list -C > [local] global counter uptime perf mono mono_raw boot x86-tsc > > Thanks for looking at it! Bah, I was hoping it would show "[global]" as we just discovered a bug because the global clock took a spin lock and a recent change allowed it to recurse once (causing a deadlock if it happened). But the "[local]" clock has no such issue. Which means I need to do a bit more digging into this cause :-( -- Steve