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 X-Spam-Level: X-Spam-Status: No, score=-5.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS, URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C3EBAC10F13 for ; Mon, 8 Apr 2019 19:38:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8E05A20880 for ; Mon, 8 Apr 2019 19:38:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554752288; bh=oCZj0I6q+HNknBYs8/M9pFSRm3fQO+nY7ODd0WPZWu8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=Vxx1I5YY5pgivrupMqyYjBJCHq8lvD7FdaDDaxD9u6AKKBpsS1PrGYG/sYCMYZLSF Jlf9JxoeyVxcIlWd4VqwXMvSPCK5wR1g8xB2w8Ov9zltXfE5HnbvK/f6MCqWzgzaUQ /5ULps+Eb/sDb36i3ZbEkWTjTtGE8TxjFznkllPQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727536AbfDHTiH (ORCPT ); Mon, 8 Apr 2019 15:38:07 -0400 Received: from mail-yb1-f194.google.com ([209.85.219.194]:37512 "EHLO mail-yb1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726558AbfDHTiG (ORCPT ); Mon, 8 Apr 2019 15:38:06 -0400 Received: by mail-yb1-f194.google.com with SMTP id p134so4936675ybc.4 for ; Mon, 08 Apr 2019 12:38:06 -0700 (PDT) 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=PlrrD0hKadd0rsLNpkqwRfBpObSey3Ho11gqeYD66us=; b=UvMo9ulVi7Ou9z2aXoNhHXGdSRajUFhxUfauEEwu3UvmKVBBDowJiRCphNCv4fB8Jt p9brI90+Fzs23xfXmAblZPUo97WMXOV2RKCaYM4hZpIyBp9a19D2BL48JhT3YqNZKxOe BoETtYLEWglixWPPe1Wd9+9p4OssmecWSZ8kmEmwZ7aiM8qDpl9gAKY818q5neLj/Joz sKwBwOUlFKdP4SyHjoxj66644aiJiE02nYv76lrEa90N5LL/ekUZH7DLA/Is7gDKajSc ojGJNjDceGRHFxFxvGEnUpVQNk3SXK9wH6M/GvM+eU3kZ1lPs7S77siW/P+IFEoVBBL1 B7LQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to:user-agent; bh=PlrrD0hKadd0rsLNpkqwRfBpObSey3Ho11gqeYD66us=; b=DmRcmTII810aosa27O7Jbb6fPngtVUM9vb3CO0eR5hcBE49+hk81yYrMh/rz/q8rbf zDf1ohYe5w55M3J+AnhUkTSGE9b9AqedDY64J8ObI+GPDmv6JSpFhHpoS5l9KTLe/MXC Dq0TB4AxXETyoxRLeBbwDXah16hLvR2fQ9Nhk6Wv7akcIdBWvY9Q7++80w1qPBT/T/xY Y4Vw6KBZhntmMxzDD/GIkmuDdt3vrwtG9VKKbSXTjTxr1Q0yzGpH6Fm2bpE7TUCP4xI5 CEF3Ptua9Nq2u/RiUOJ2IJFnPUxwi0zvOE7cABdhYoZKPlsc0JOFeOwRNtOWf+ai1J0q dsvw== X-Gm-Message-State: APjAAAUf+gdDncIS1o7RaaMEKruw4YFKYrJCkFkNZbXkQdJZ238GiF0Q H7eilcwaZ2E1yvVDvUUplFQ= X-Google-Smtp-Source: APXvYqzM4v9PrEeh76yvS2p1w93RgXeOHXSsjlRkpkFsc+XGuXmhdCLBS0T4kJ1CJDevI1wFp1DJwg== X-Received: by 2002:a5b:50f:: with SMTP id o15mr23315004ybp.54.1554752285369; Mon, 08 Apr 2019 12:38:05 -0700 (PDT) Received: from localhost ([2620:10d:c091:200::3:135c]) by smtp.gmail.com with ESMTPSA id v123sm10915515ywv.89.2019.04.08.12.38.04 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 08 Apr 2019 12:38:04 -0700 (PDT) Date: Mon, 8 Apr 2019 12:38:02 -0700 From: Tejun Heo To: Sebastian Andrzej Siewior Cc: linux-kernel@vger.kernel.org, Lai Jiangshan , Ingo Molnar , Peter Zijlstra , Thomas Gleixner Subject: Re: [PATCH 1/2] workqueue: Use normal rcu Message-ID: <20190408193802.GJ1975820@devbig004.ftw2.facebook.com> References: <20190313165548.19713-1-bigeasy@linutronix.de> <20190313165548.19713-2-bigeasy@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190313165548.19713-2-bigeasy@linutronix.de> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Mar 13, 2019 at 05:55:47PM +0100, Sebastian Andrzej Siewior wrote: > From: Thomas Gleixner > > There is no need for sched_rcu. The undocumented reason why sched_rcu > is used is to avoid a few explicit rcu_read_lock()/unlock() pairs by > the fact that sched_rcu reader side critical sections are also protected > by preempt or irq disabled regions. > > Replace rcu_read_lock_sched with rcu_read_lock and acquire the RCU lock > where it is not yet explicit acquired. Replace local_irq_disable() with > rcu_read_lock(). Update asserts. > > Signed-off-by: Thomas Gleixner > [bigeasy: mangle changelog a little] > Signed-off-by: Sebastian Andrzej Siewior Applied to wq/for-5.2. Thanks. -- tejun