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=0.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,HK_RANDOM_FROM,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED 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 48E96C3A5A2 for ; Fri, 23 Aug 2019 12:56:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1EDC322CEC for ; Fri, 23 Aug 2019 12:56:50 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="iQF17QvR" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2395071AbfHWM4t (ORCPT ); Fri, 23 Aug 2019 08:56:49 -0400 Received: from mail-io1-f68.google.com ([209.85.166.68]:43079 "EHLO mail-io1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732092AbfHWM4q (ORCPT ); Fri, 23 Aug 2019 08:56:46 -0400 Received: by mail-io1-f68.google.com with SMTP id 18so19760426ioe.10 for ; Fri, 23 Aug 2019 05:56:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=XID+uEqMpo1msXzHrPG2vXSXUSZE5du4xRV16C8TdVE=; b=iQF17QvRNQaaa/SIlshzYQUZu/ekcylkeuAJeL6K9WbpMM0NllsteRFxJevNe0+vQM xiRVHpq1kNDbKoXS8G+VBhpqrKp5J3tWcXCh7mEAU63XCNhmmgP3rRJCfYqPH3MfWpRA i3kR29HYF4+GmI4vnVvvHDisZ3wyvwk34QgKZIerZ1y5D/8elj6mAxWeob51zj2Vu7eq WMG+JTt0XB21g+Ra+FeXzEkQLFdcPnFRd9hkI8yurwRog7ZVPu40P9xoV9thk7XiBrJC LnN4UN+IoFjyVohCLbJtxZwJOvjPBirv78eVraj91gXl74uiqGTf1B3b1YW/aBGnLrH3 Dqxw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=XID+uEqMpo1msXzHrPG2vXSXUSZE5du4xRV16C8TdVE=; b=egn/QlrXSKK4MnsTeCX/PtyLBw1vCIiffMWBSAT3XWS+ZzJYglnwsc1I9sqAswSAod ZmUHnJQpbej896ywhYLebBFftiIR6eOtker/vxSiLyNZVapJkB8+N3dkAXbtk1Mmfp87 AwbGH4aJJeIZQCmpbjGXd6/sSnCfNbyGm13EU8Y1s8aXlg9fsUuQkJ/ohhHeOWd1th3A FZ0xwFnI2ce1fZFZiOH4Dhw9My2aeqFWzduWtz/POmlmC4FIueVZaRt1LBbYjyxApWUN Nld/ZC/FN+1E6Sm7SpBCPQP1cl6q8SS0VEzxTiI6X6lphUQy6gRFTtuIye5feJv8DkaP xSew== X-Gm-Message-State: APjAAAVfqDgGNxSFeuGGofQV00FVKXjKWglxABW4n6JTuhwZnrmVxE95 /X9zQt86TMeaD3MIHMlf0eQskYPuoZlyZ/UnWfRHOr7V X-Google-Smtp-Source: APXvYqwima7WTSlzAySQFeHBINGCr77JSflI0BPv/RYgV6+cgWpOR6GK8sOj0uki2rcOaPN0EFFNxtz7TnCEMxjG6Qw= X-Received: by 2002:a5e:8e09:: with SMTP id a9mr6632065ion.238.1566565005719; Fri, 23 Aug 2019 05:56:45 -0700 (PDT) MIME-Version: 1.0 References: <20190601082722.44543-1-irogers@google.com> <20190621082422.GH3436@hirez.programming.kicks-ass.net> <20190624075520.GC3436@hirez.programming.kicks-ass.net> <20190823115946.GM2349@hirez.programming.kicks-ass.net> In-Reply-To: <20190823115946.GM2349@hirez.programming.kicks-ass.net> From: Ganapatrao Kulkarni Date: Fri, 23 Aug 2019 18:26:34 +0530 Message-ID: Subject: Re: [PATCH] perf cgroups: Don't rotate events for cgroups unnecessarily To: Peter Zijlstra Cc: Ian Rogers , Ingo Molnar , Arnaldo Carvalho de Melo , Alexander Shishkin , Jiri Olsa , Namhyung Kim , LKML , Kan Liang , Andi Kleen , Stephane Eranian , Ganapatrao Kulkarni , Jayachandran Chandrasekharan Nair Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Peter, On Fri, Aug 23, 2019 at 5:29 PM Peter Zijlstra wrote: > > > A: Because it messes up the order in which people normally read text. > Q: Why is top-posting such a bad thing? > A: Top-posting. > Q: What is the most annoying thing in e-mail? Sorry for the top-posting. > > On Fri, Aug 23, 2019 at 04:13:46PM +0530, Ganapatrao Kulkarni wrote: > > > We are seeing regression with our uncore perf driver(Marvell's > > ThunderX2, ARM64 server platform) on 5.3-Rc1. > > After bisecting, it turned out to be this patch causing the issue. > > Funnily enough; the email you replied to didn't contain a patch. Hmm sorry, not sure why the patch is clipped-off, I see it in my inbox. > > > Test case: > > Load module and run perf for more than 4 events( we have 4 counters, > > event multiplexing takes place for more than 4 events), then unload > > module. > > With this sequence of testing, the system hangs(soft lockup) after 2 > > or 3 iterations. Same test runs for hours on 5.2. > > > > while [ 1 ] > > do > > rmmod thunderx2_pmu > > modprobe thunderx2_pmu > > perf stat -a -e \ > > uncore_dmc_0/cnt_cycles/,\ > > uncore_dmc_0/data_transfers/,\ > > uncore_dmc_0/read_txns/,\ > > uncore_dmc_0/config=0xE/,\ > > uncore_dmc_0/write_txns/ sleep 1 > > sleep 2 > > done > > Can you reproduce without the module load+unload? I don't think people > routinely unload modules. The issue wont happen, if module is not unloaded/reloaded. IMHO, this could be potential bug! > > Thanks, Ganapat