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=-3.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no 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 36BC6C433E0 for ; Fri, 7 Aug 2020 19:02:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 139892086A for ; Fri, 7 Aug 2020 19:02:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="mOhZcWgJ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726361AbgHGTCP (ORCPT ); Fri, 7 Aug 2020 15:02:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59152 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726030AbgHGTCP (ORCPT ); Fri, 7 Aug 2020 15:02:15 -0400 Received: from merlin.infradead.org (merlin.infradead.org [IPv6:2001:8b0:10b:1231::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C36A1C061756 for ; Fri, 7 Aug 2020 12:02:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=dSQ55qZF/+1KL/4yLTuSgU8vfCk1Ou9csjN0s+BgZsQ=; b=mOhZcWgJWpWQU6juOT8JoylJOH 6NAKNS6fxdeiYpEl/3VapaW3X3YztfZG0OQ6Rj3r7lPMzRtvlrhD9hCUPXlmUkFXd+hIUdBQYwIzW JyrMYzfvyVfTef1+7aqpmhWJ3kXntbxKqOSFNNVu5+HCMFzZ5qFq0xlRl4AawhvPkF6izv+2XSca/ FY/mw5SqPWXXDZXHQipHdtmhSho2Xd0CS9BND7L1SdCGHHw+eiXDn1jfm/qXE/0Vd0u9HXbxId+7S l9BtW+b4w+IgLf5xkc9AqpytPMHFgTKzBRlk8fVbJmhXV5PGyn3vCLPuj07tuU/RHjRsh9opf3HPz 9nkPKyug==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1k47d3-0003CW-60; Fri, 07 Aug 2020 19:02:09 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id AEBA13010D2; Fri, 7 Aug 2020 21:02:04 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 8391E200D415D; Fri, 7 Aug 2020 21:02:04 +0200 (CEST) Date: Fri, 7 Aug 2020 21:02:04 +0200 From: peterz@infradead.org To: Mathieu Desnoyers Cc: Peter Oskolkov , Peter Oskolkov , paulmck , linux-kernel , Paul Turner , Chris Kennelly Subject: Re: [PATCH 1/2] membarrier: add MEMBARRIER_CMD_PRIVATE_RESTART_RSEQ_ON_CPU Message-ID: <20200807190204.GN2674@hirez.programming.kicks-ass.net> References: <20200806000859.160882-1-posk@google.com> <20200806134828.GA165568@hirez.programming.kicks-ass.net> <1668913120.1621.1596735425601.JavaMail.zimbra@efficios.com> <1689650939.2607.1596823679392.JavaMail.zimbra@efficios.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1689650939.2607.1596823679392.JavaMail.zimbra@efficios.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Aug 07, 2020 at 02:07:59PM -0400, Mathieu Desnoyers wrote: > One thing I find weird about Peter's patch is that it adds a > MEMBERRIER_CMD_PRIVATE_EXPEDITED_RSEQ without a corresponding > MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED_RSEQ. Considering that > the SYNC_CORE variant already has its own register command, I > find it weird that the RSEQ counterpart does not have one. I thought the register thing was about global, not private membarriers. Anyway, it was just a quick pseudo thing to show how one can go about adding the rseq to the mm iteration we already have.