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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A95C7E7B5E2 for ; Wed, 4 Oct 2023 09:36:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242007AbjJDJg4 (ORCPT ); Wed, 4 Oct 2023 05:36:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55312 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232956AbjJDJgz (ORCPT ); Wed, 4 Oct 2023 05:36:55 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 14B5AAC; Wed, 4 Oct 2023 02:36:52 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5D508C433C9; Wed, 4 Oct 2023 09:36:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1696412211; bh=mFEKlHahuJsICiDMySGxK7ORPKhGXJhp560qFnvIK6A=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ab4/sxLDgwGHrrYBzlGL/GS5cDksAXca8QM+qTGrIRk1Plg9ZId5Cqh2N9pkr2yWp Vy+GCThHWMHC8ESG5ZWF7H8gP6Qvy5ZjsmRyqpYUX5XdCWKu+PEqaT6wcvtPFKVatU julVxL4cUaOcLSij4F/iyAM8wYsq6iDNn9vCE3mFno+i/eS/nE5XJt2s91o5YXViT3 H/qeKch+XDbFz+H2RdJJK5SEIs/RW5bBLGUECBYXpyHOyPJC7VXEkWnWTQoO1q6wln aI57YFsff1izAk8sxqfB5alrWjIWY7oo8wtIEdxkheVsMjS0jPkftqI174JrC5c3rK 84EuFm6NAW2UQ== Date: Wed, 4 Oct 2023 11:36:49 +0200 From: Frederic Weisbecker To: "Paul E. McKenney" Cc: LKML , Yong He , Neeraj upadhyay , Joel Fernandes , Boqun Feng , Uladzislau Rezki , RCU Subject: Re: [PATCH 0/5] srcu fixes Message-ID: References: <20231003232903.7109-1-frederic@kernel.org> <1d21ceee-56d3-4784-9e6f-0a766c773833@paulmck-laptop> <811d08e3-efb8-4398-8fbc-6b5d030afb15@paulmck-laptop> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <811d08e3-efb8-4398-8fbc-6b5d030afb15@paulmck-laptop> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Oct 03, 2023 at 08:30:45PM -0700, Paul E. McKenney wrote: > On Tue, Oct 03, 2023 at 08:21:42PM -0700, Paul E. McKenney wrote: > > On Tue, Oct 03, 2023 at 05:35:31PM -0700, Paul E. McKenney wrote: > > > On Wed, Oct 04, 2023 at 01:28:58AM +0200, Frederic Weisbecker wrote: > > > > Hi, > > > > > > > > This contains a fix for "SRCU: kworker hung in synchronize_srcu": > > > > > > > > http://lore.kernel.org/CANZk6aR+CqZaqmMWrC2eRRPY12qAZnDZLwLnHZbNi=xXMB401g@mail.gmail.com > > > > > > > > And a few cleanups. > > > > > > > > Passed 50 hours of SRCU-P and SRCU-N. > > > > > > > > git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git > > > > srcu/fixes > > > > > > > > HEAD: 7ea5adc5673b42ef06e811dca75e43d558cc87e0 > > > > > > > > Thanks, > > > > Frederic > > > > > > Very good, and a big "Thank You!!!" to all of you! > > > > > > I queued this series for testing purposes, and have started a bunch of > > > SRCU-P and SRCU-N tests on one set of systems, and a single SRCU-P and > > > SRCU-N on another system, but with both scenarios resized to 40 CPU each. > > The 200*1h of SRCU-N and the 100*1h of SRCU-p passed other than the usual > tick-stop errors. (Is there a patch for that one?) The 40-CPU SRCU-N > run was fine, but the 40-CPU SRCU-P run failed due to the fanouts setting > a maximum of 16 CPUs. So I started a 10-hour 40-CPU SRCU-P and a pair > of 10-hour 16-CPU SRCU-N runs on one system, and 200*10h of SRCU-N and > 100*10h of SRCU-P. > > I will let you know how it goes. Very nice! It might be worth testing the first patch alone as well if we backport only this one. Thanks! > Thanx, Paul > > > > While that is in flight, a few questions: > > > > > > o Please check the Co-developed-by rules. Last I knew, it was > > > necessary to have a Signed-off-by after each Co-developed-by. > > > > > > o Is it possible to get a Tested-by from the original reporter? > > > Or is this not reproducible? > > > > > > o Is it possible to convince rcutorture to find this sort of > > > bug? Seems like it should be, but easy to say... > > > > And one other thing... > > > > o What other bugs like this one are hiding elsewhere > > in RCU? > > > > > o Frederic, would you like to include this in your upcoming > > > pull request? Or does it need more time? > > > > Thanx, Paul > > > > > > --- > > > > > > > > Frederic Weisbecker (5): > > > > srcu: Fix callbacks acceleration mishandling > > > > srcu: Only accelerate on enqueue time > > > > srcu: Remove superfluous callbacks advancing from srcu_start_gp() > > > > srcu: No need to advance/accelerate if no callback enqueued > > > > srcu: Explain why callbacks invocations can't run concurrently > > > > > > > > > > > > kernel/rcu/srcutree.c | 55 ++++++++++++++++++++++++++++++++++++--------------- > > > > 1 file changed, 39 insertions(+), 16 deletions(-)