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 lists.zx2c4.com (lists.zx2c4.com [165.227.139.114]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 5C11AC43334 for ; Wed, 6 Jul 2022 20:42:08 +0000 (UTC) Received: by lists.zx2c4.com (OpenSMTPD) with ESMTP id 30b1f09d; Wed, 6 Jul 2022 20:42:06 +0000 (UTC) Received: from dfw.source.kernel.org (dfw.source.kernel.org [2604:1380:4641:c500::1]) by lists.zx2c4.com (OpenSMTPD) with ESMTPS id a17cc38c (TLSv1.2:ECDHE-ECDSA-AES256-GCM-SHA384:256:NO) for ; Wed, 6 Jul 2022 20:42:05 +0000 (UTC) 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 dfw.source.kernel.org (Postfix) with ESMTPS id 433D1620E7; Wed, 6 Jul 2022 20:42:03 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9DEDFC3411C; Wed, 6 Jul 2022 20:42:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1657140122; bh=pe7a6K472B35Fk1ZLJZNNAu/QA2Cq/X9L9IX5KemqnU=; h=Date:From:To:Cc:Subject:Reply-To:References:In-Reply-To:From; b=qurE6YFdbVvNvVoeXgoZcqxGE70mjJwBH7VgzxFINrciQcq8BLjc+FeG4xNN93Pe2 H/LtYDggW0IcPgC2CZC0Lc8R17IIgPuXjBNeRVG1v5QQ+PYuYc/qyJ8Xbi4v8j/IjM iIc+nz4KDPB5AH9D+w8VV4qFYg7gJiQlww9o22b8B6QBTV897KH+gsuhmtqqG4xKfs cKe08VA1ykzmn54D2oNKC9IUT5tmylPHbG5InZ/V0KYLGOq0XW+ZLu+0x8apQs0mcg GFtEAkNGxEAszeaPzpBKxdcsmP1BgcwFmD1WHvMe1LUuzxgayYXPekA71qM6uFZn40 sY92334nGM1yQ== Received: by paulmck-ThinkPad-P17-Gen-1.home (Postfix, from userid 1000) id 369B35C0F78; Wed, 6 Jul 2022 13:42:02 -0700 (PDT) Date: Wed, 6 Jul 2022 13:42:02 -0700 From: "Paul E. McKenney" To: Uladzislau Rezki Cc: Christian =?iso-8859-1?Q?K=F6nig?= , "Alex Xu (Hello71)" , wireguard@lists.zx2c4.com, "Jason A. Donenfeld" , Joel Fernandes , Greg Kroah-Hartman , Xinhui.Pan@amd.com, linux-kernel@vger.kernel.org, amd-gfx@lists.freedesktop.org, Suren Baghdasaryan , rcu@vger.kernel.org, Hridya Valsaraju , Arve =?iso-8859-1?B?SGr4bm5lduVn?= , Theodore Ts'o , alexander.deucher@amd.com, Todd Kjos , uladzislau.rezki@sony.com, Martijn Coenen , Christian Brauner Subject: Re: CONFIG_ANDROID (was: rcu_sched detected expedited stalls in amdgpu after suspend) Message-ID: <20220706204202.GJ1790663@paulmck-ThinkPad-P17-Gen-1> References: <1656379893.q9yb069erk.none@localhost> <20220628041252.GV1790663@paulmck-ThinkPad-P17-Gen-1> <1656421946.ic03168yc3.none@localhost> <20220628185437.GA1790663@paulmck-ThinkPad-P17-Gen-1> <1656443915.mdjoauhqe0.none@localhost> <79c6ad70-47d9-47fe-4bb4-33fcf356dd37@amd.com> <20220706175836.GI1790663@paulmck-ThinkPad-P17-Gen-1> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-BeenThere: wireguard@lists.zx2c4.com X-Mailman-Version: 2.1.30rc1 Precedence: list List-Id: Development discussion of WireGuard List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: paulmck@kernel.org Errors-To: wireguard-bounces@lists.zx2c4.com Sender: "WireGuard" On Wed, Jul 06, 2022 at 08:09:49PM +0200, Uladzislau Rezki wrote: > On Wed, Jul 06, 2022 at 10:58:36AM -0700, Paul E. McKenney wrote: > > On Wed, Jul 06, 2022 at 07:48:20PM +0200, Uladzislau Rezki wrote: > > > Hello. > > > > > > On Mon, Jul 04, 2022 at 01:30:50PM +0200, Christian König wrote: > > > > Hi guys, > > > > > > > > Am 28.06.22 um 22:11 schrieb Uladzislau Rezki: > > > > > > Excerpts from Paul E. McKenney's message of June 28, 2022 2:54 pm: > > > > > > > All you need to do to get the previous behavior is to add something like > > > > > > > this to your defconfig file: > > > > > > > > > > > > > > CONFIG_RCU_EXP_CPU_STALL_TIMEOUT=21000 > > > > > > > > > > > > > > Any reason why this will not work for you? > > > > > > > > sorry for jumping in so later, I was on vacation for a week. > > > > > > > > Well when any RCU period is longer than 20ms and amdgpu in the backtrace my > > > > educated guess is that we messed up some timeout waiting for the hw. > > > > > > > > We usually do wait a few us, but it can be that somebody is waiting for ms > > > > instead. > > > > > > > > So there are some todos here as far as I can see and It would be helpful to > > > > get a cleaner backtrace if possible. > > > > > > > Actually CONFIG_ANDROID looks like is going to be removed, so the CONFIG_RCU_EXP_CPU_STALL_TIMEOUT > > > will not have any dependencies on the CONFIG_ANDROID anymore: > > > > > > https://lkml.org/lkml/2022/6/29/756 > > > > But you can set the RCU_EXP_CPU_STALL_TIMEOUT Kconfig option, if you > > wish. Setting this option to 20 will get you the behavior previously > > obtained by setting the now-defunct ANDROID Kconfig option. > > > Right. Or over boot parameter. So for us it is not a big issue :) Specifically rcupdate.rcu_exp_cpu_stall_timeout, for those just now tuning in. ;-) Thanx, Paul