Received: by 2002:ad5:474a:0:0:0:0:0 with SMTP id i10csp951588imu; Thu, 13 Dec 2018 07:08:18 -0800 (PST) X-Google-Smtp-Source: AFSGD/VifSaDBaFqpiOIb8IPrecxEnL/J1GFoW7KM4FaiJC3Q2w8OJWpm6/CrsYl0d/0+LPzyYdt X-Received: by 2002:a17:902:b592:: with SMTP id a18mr23952252pls.293.1544713698601; Thu, 13 Dec 2018 07:08:18 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1544713698; cv=none; d=google.com; s=arc-20160816; b=Z7cJ3IVklalXeAvfwd0nQxQomSpZ9c5IkbGUPf+kf5WeO8A+aZ5gLTXf49A6LU1fM6 HF9Ig9uVeOyrFvd/0J1SMROMvuFqMMxfpiOp50zPXlza22118SMBtU5UBv3ejmSwkgA+ wVlsWkYh5wZeTsOPBYOYCZyK2uTUOb680nCmytJW438uQdE34OhrDKY1rgOEWBUPgP4P z/1W55kFhxbUxSZsUyZdNa3eAxM5WwUvleoDP6+O7XgwDAhKtxNf+FszlAIz6qH8L0GG yK0Q9+VRr2y8Y6n+hekq/mLOxnpg2PpbbQUTcJWbVBmaTdCfoRDS1zGkCviKSC++ovTa p+HQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:user-agent:in-reply-to :content-disposition:mime-version:references:message-id:subject:cc :to:from:date; bh=faIj76stAqLYPwMvX++vNSGIIQ8W/Ga2fEeQeQ0wc8A=; b=m+e0s9abC3sc2CFxg646OAxEBMf7rHTrnar2wp3b72gpIxzQ8T6uxDW8ywQ4T7U+Ta rsGCbTpT2pyqMwX6AkczpXtjeKgEX3VFDOfgEnqHDQQaqmRMMOQkoiifhP+WHvgVkcqh diI9azOHD4ilx+kajnDURsYo0qV018cnv6QtiqYL0rQmh+Y+XEBTGiNvc+xXOEykl2yC 6EW36aW6RLiEilNMbWa9IF1o/gCLFOpzB2CiUGjENEkShIn7Aa1A7CZmDIasC3Z20hiB /WGMNZvqwoXJss07Ag99kdXsj8mFMIMJttNVLZKOyV/c0QP+4ZSH8Zzuvgf/0IB40hDz avbA== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id o89si1754451pfk.223.2018.12.13.07.07.56; Thu, 13 Dec 2018 07:08:18 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729512AbeLMPEE (ORCPT + 99 others); Thu, 13 Dec 2018 10:04:04 -0500 Received: from Galois.linutronix.de ([146.0.238.70]:46811 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728620AbeLMPED (ORCPT ); Thu, 13 Dec 2018 10:04:03 -0500 Received: from bigeasy by Galois.linutronix.de with local (Exim 4.80) (envelope-from ) id 1gXSWs-0002QC-PF; Thu, 13 Dec 2018 16:03:58 +0100 Date: Thu, 13 Dec 2018 16:03:58 +0100 From: Sebastian Andrzej Siewior To: Boqun Feng Cc: Joel Fernandes , linux-kernel@vger.kernel.org, Lai Jiangshan , "Paul E. McKenney" , Josh Triplett , Steven Rostedt , Mathieu Desnoyers , tglx@linutronix.de, tj@kernel.org Subject: Re: [PATCH] srcu: Remove srcu_queue_delayed_work_on() Message-ID: <20181213150358.bgrwgpp5am5w53ie@linutronix.de> References: <20181211111238.13474-1-bigeasy@linutronix.de> <20181212014016.GA97542@google.com> <20181212140519.GA10937@tardis> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20181212140519.GA10937@tardis> User-Agent: NeoMutt/20180716 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2018-12-12 22:05:19 [+0800], Boqun Feng wrote: > So Jiangshan and TJ, what's your opion on this one? If we call a > queue_work_on() at a place where that target cpu may be offlined, I > think we have the guarantee that the work will be eventually executed > even if the cpu is never online again, right? In other words, if a cpu > has been online once, queue_work_on() on it will be free from racing > with cpu hotplug. > > Am I right about this, or did I miss something subtle? tj answered this one: https://lkml.kernel.org/r/20180919205521.GE902964@devbig004.ftw2.facebook.com > Regards, > Boqun Sebastian