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 5AA4DC433EF for ; Mon, 14 Mar 2022 20:26:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245002AbiCNU12 (ORCPT ); Mon, 14 Mar 2022 16:27:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56866 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240478AbiCNU11 (ORCPT ); Mon, 14 Mar 2022 16:27:27 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 06A573917E for ; Mon, 14 Mar 2022 13:26:16 -0700 (PDT) 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 ams.source.kernel.org (Postfix) with ESMTPS id 80387B80FE7 for ; Mon, 14 Mar 2022 20:26:12 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 14461C340E9; Mon, 14 Mar 2022 20:26:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1647289571; bh=9CS29+T32I+TMcpS8styzHO75+JE2E1H4hCtaXxugCo=; h=Date:From:To:Cc:Subject:Reply-To:References:In-Reply-To:From; b=Mn55mgnVDnSmww/J8Y1UBj81s5MHWoXrfl7RpaF1LZjVgNAaWNsomIdpdipfI/xyb /ZUmzyto56XCK21Q/XSP4j+s6qosm5nuH8IssEhYg7TqUqrz59ku2mq7By3oF2vaAm NPZLKlf1Qn4YDyfuz8nC7DCUqo8eTbr6BuWOnZp//C565POnsO/vkn89LSmkm1B3sm RApIfb/H11md0Edk/j5lkHNREhtpauYb6rOoWk1Zlk7fuO5v/omL2bgoYfje/lKHa8 z6YzKgGzHy26zI93Fmik4rFYqpjOGoJTxWvTdDkZpYJMnYZxD9NXTgNPTBcym6IsnD nYiN/9Y7KkrVw== Received: by paulmck-ThinkPad-P17-Gen-1.home (Postfix, from userid 1000) id ACA5E5C4162; Mon, 14 Mar 2022 13:26:10 -0700 (PDT) Date: Mon, 14 Mar 2022 13:26:10 -0700 From: "Paul E. McKenney" To: Frederic Weisbecker Cc: LKML , Peter Zijlstra , Marco Elver , Neeraj Upadhyay , Valentin Schneider , Boqun Feng , Uladzislau Rezki , Joel Fernandes Subject: Re: [PATCH 0/3] rcu: synchronize_rcu[_expedited]() related fixes Message-ID: <20220314202610.GW4285@paulmck-ThinkPad-P17-Gen-1> Reply-To: paulmck@kernel.org References: <20220314133738.269522-1-frederic@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220314133738.269522-1-frederic@kernel.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Mar 14, 2022 at 02:37:35PM +0100, Frederic Weisbecker wrote: > > A few fixes especially for expedited GP polling causing a stall on TREE07, > as reported by Paul. > > We may still want to optimize start_poll_synchronize_rcu_expedited() on > UP-no-preempt but I think Paul may be implying this while doing other > fixes. > > git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git > rcu/dev > > HEAD: 6e5fd7e614fd5c8f0fffeaa140b7ea697bfeb096 > > Thanks, > Frederic I have pulled these in for review and testing, thank you!!! I have started a ~90-minute test and will let you know how that goes. > --- > > Frederic Weisbecker (2): > rcu: Fix expedited GP polling against UP/no-preempt environment I have some concerns with this one due to the fact that it acquires locks in cases where the old code would not. (I did have problems with this in both recent SRCU changes and the normal-grace-period counterpart to this series.) But let's see what rcutorture and kbuild test robot think about it. > rcu: Fix preemption mode check on synchronize_rcu[_expedited]() This one looks good. > Valentin Schneider (1): > preempt/dynamic: Introduce preempt mode accessors I am guessing that this one is a compact placeholder for my convenience (in which case thank you!). I will be marking it "EXP" on my next rebase. Thanx, Paul > include/linux/sched.h | 16 +++++++++++++++ > kernel/rcu/tree.c | 2 +- > kernel/rcu/tree_exp.h | 57 +++++++++++++++++++++++++++++++-------------------- > kernel/sched/core.c | 11 ++++++++++ > 4 files changed, 63 insertions(+), 23 deletions(-)