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=-2.4 required=3.0 tests=DKIM_SIGNED, MAILING_LIST_MULTI,SPF_PASS,T_DKIM_INVALID,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 13BF6C4321D for ; Fri, 17 Aug 2018 16:08:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C115F21788 for ; Fri, 17 Aug 2018 16:08:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="go0xzKAC" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C115F21788 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727686AbeHQTMm (ORCPT ); Fri, 17 Aug 2018 15:12:42 -0400 Received: from mail-yw1-f67.google.com ([209.85.161.67]:39234 "EHLO mail-yw1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727160AbeHQTMl (ORCPT ); Fri, 17 Aug 2018 15:12:41 -0400 Received: by mail-yw1-f67.google.com with SMTP id r184-v6so4552606ywg.6 for ; Fri, 17 Aug 2018 09:08:45 -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=vcbqEx7UFdEFmAEgSGZ271EXkgERQAEZnIF3GSD3LOU=; b=go0xzKACUlP7N2xKSOBNC7n1f82WAbVqwbzwVzbtQmNeqAwAnlNATLNEk2xmNKG421 djKUfM27wn6gHEFQQwVXyOmqy4GzHwIKOYKiIvwp90LwrSiozURsSs+mKz6OiYCt3nWz GT/briDv5OaDKo42q/bLwlktIEcN7Es+ASw06nJv9LBLaYhZtd0H3ouBwERODKkuINHW ViSYNxZcJJToB+nfROBhe0wDeU/sy3cQWp9EMVwED4CftkUtXX5D6JBJU27Vgkff3m5z p+T75aFJzQew8MrhpvqAHwvaFhzNedRy5cpIvdh0An41ryPRIe+NNAK1Wfe8JiA1MwM3 at0A== 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=vcbqEx7UFdEFmAEgSGZ271EXkgERQAEZnIF3GSD3LOU=; b=b/BPFEH1bIOQYNJez4/C6YHXzq42QtJoruGBQH1cq8NIevJTaiaOJTtyK3rt1rLp+D sLtvJw7bU8H7BqH1lrge6E+cpAfZh0E+/MB6Fjr7OnOHfOn8XdVq9CdVD097w/BRxWU1 hIkqslAEK91pCUMIZ7dmf4B/2i6ubnrLRj7kgGcmznLng/hR5afzfVOULAn3WH5ITtwA EeTPkRXGn8gJJWJfuObTmMElpQwDeTdWpX34V8u+YWqI312M/u4yY7X6ATzZLD6ga5GF som0V9uyVSB27Da+YCfcLSpkR8VLQjJu+LdYvnUlFxt1V+wUAPa9Q4xd9MjSkJ+SI6ch SDIg== X-Gm-Message-State: AOUpUlFqpuohJAmDd6PAg3Ch9hMW8ckk7NADM5cw7YjaZ8GiJYctx0OA MXQqjiwaAjJlWSdfWuQQ+lI= X-Google-Smtp-Source: AA+uWPwlZwpg83Bnyw5WWb9id9LmbhOBgeOEPp9Qls2biCO+HFyBlA9w0fCfDAEqKGb5DwzOKQG4fA== X-Received: by 2002:a81:af23:: with SMTP id n35-v6mr18561337ywh.468.1534522125082; Fri, 17 Aug 2018 09:08:45 -0700 (PDT) Received: from localhost ([2620:10d:c091:200::2:9b8b]) by smtp.gmail.com with ESMTPSA id f5-v6sm1304037ywa.39.2018.08.17.09.08.43 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 17 Aug 2018 09:08:44 -0700 (PDT) Date: Fri, 17 Aug 2018 09:08:42 -0700 From: Tejun Heo To: "Paul E. McKenney" Cc: Steven Rostedt , joel@joelfernandes.org, mathieu.desnoyers@efficios.com, peterz@infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH RFC] Make call_srcu() available during very early boot Message-ID: <20180817160842.GK3978217@devbig004.ftw2.facebook.com> References: <20180814162448.GA20414@linux.vnet.ibm.com> <20180814124945.5cf1753f@gandalf.local.home> <20180814170618.GA24813@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180814170618.GA24813@linux.vnet.ibm.com> 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 Hello, On Tue, Aug 14, 2018 at 10:06:18AM -0700, Paul E. McKenney wrote: > > Is there a way we could make a union, or reuse one of the other fields, > > as we know that synchronize_srcu() can't be used yet (and if it is, > > either warn, or just make it a nop). And when we call srcu_init() and > > remove the srcu_struct from the list, we can then initialize whatever > > we used as the temporary boot up list field. > > I will take a look. If nothing else, I could union it with the > struct work_struct, since it cannot be used that early anyway. ;-) > > Or I could just use the work_struct that is already inside the struct > work_struct. Tejun, would you be OK with that? Hmm... not super against it given how specialized the whole thing is but maybe just making it a union is cleaner? Thanks. -- tejun