From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752471AbdLKPVL (ORCPT ); Mon, 11 Dec 2017 10:21:11 -0500 Received: from mail-qt0-f194.google.com ([209.85.216.194]:37327 "EHLO mail-qt0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751585AbdLKPVH (ORCPT ); Mon, 11 Dec 2017 10:21:07 -0500 X-Google-Smtp-Source: ACJfBos1YUKg1Es1g5kxksCrjf1leUlTr6neBn6jIENGUgbxKAzJILJ+pPkDm5fE+Wm2gZ6OTWmafA== Date: Mon, 11 Dec 2017 07:20:59 -0800 From: Tejun Heo To: Peter Zijlstra Cc: Prateek Sood , avagin@gmail.com, mingo@kernel.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, sramana@codeaurora.org Subject: Re: [PATCH] cgroup/cpuset: fix circular locking dependency Message-ID: <20171211152059.GH2421075@devbig577.frc2.facebook.com> References: <1511868946-23959-1-git-send-email-prsood@codeaurora.org> <623f214b-8b9a-f967-7a3d-ca9c06151267@codeaurora.org> <20171204202219.GF2421075@devbig577.frc2.facebook.com> <20171204225825.GP2421075@devbig577.frc2.facebook.com> <20171204230117.GF20227@worktop.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20171204230117.GF20227@worktop.programming.kicks-ass.net> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, Peter. On Tue, Dec 05, 2017 at 12:01:17AM +0100, Peter Zijlstra wrote: > > AFAICS, this should remove the circular dependency you originally > > reported. I'll revert the two cpuset commits for now. > > So I liked his patches in that we would be able to go back to > synchronous sched_domain building. Ah, yeah, that's a separate issue but didn't we intentionally make that asynchronous? IIRC, cpuset migration can take a really long time when the memory migration is turned on and doing that synchronously could mess up the system. Thanks. -- tejun From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: [PATCH] cgroup/cpuset: fix circular locking dependency Date: Mon, 11 Dec 2017 07:20:59 -0800 Message-ID: <20171211152059.GH2421075@devbig577.frc2.facebook.com> References: <1511868946-23959-1-git-send-email-prsood@codeaurora.org> <623f214b-8b9a-f967-7a3d-ca9c06151267@codeaurora.org> <20171204202219.GF2421075@devbig577.frc2.facebook.com> <20171204225825.GP2421075@devbig577.frc2.facebook.com> <20171204230117.GF20227@worktop.programming.kicks-ass.net> Mime-Version: 1.0 Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=khQrf6k8pmJPKHE8MSb0299s7kNzzoGj7xY5aJ9DKFw=; b=NHhQPZZ7MJRWQMGZzaf7l+KEBh4Qz3UAtN+ILF0p1LRI8yQ6ja8VOEnjtJn3dknYr3 kzLx+YLMbQllMn1JsBg25JNiNmyrgFG93S2okyZcb4KmzGmEPIP7t4KvtEissZyMT0UT YH/2oNvkMZJCqVvUMTPB0aclC4pjHazoAcrsZ2oMAIB/g6s/apZYlBHV5crMpm7zMI33 jdZjowDTOpA7d09ufEq6Z4/O7JgXtzySJNKMRl4+5w/PpyK02BIS3IMxImqiitrcxSxK UzKt/+OGxgabebUrerUqbHQfS68t+iW47y+wqGDjZKlwY50aC9Eekg+Eo8j5Th0/aCYk htJA== Content-Disposition: inline In-Reply-To: <20171204230117.GF20227-IIpfhp3q70z/8w/KjCw3T+5/BudmfyzbbVWyRVo5IupeoWH0uzbU5w@public.gmane.org> Sender: cgroups-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Peter Zijlstra Cc: Prateek Sood , avagin-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, mingo-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, sramana-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org Hello, Peter. On Tue, Dec 05, 2017 at 12:01:17AM +0100, Peter Zijlstra wrote: > > AFAICS, this should remove the circular dependency you originally > > reported. I'll revert the two cpuset commits for now. > > So I liked his patches in that we would be able to go back to > synchronous sched_domain building. Ah, yeah, that's a separate issue but didn't we intentionally make that asynchronous? IIRC, cpuset migration can take a really long time when the memory migration is turned on and doing that synchronously could mess up the system. Thanks. -- tejun