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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 8E84EC64E90 for ; Mon, 30 Nov 2020 09:31:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 324DF20809 for ; Mon, 30 Nov 2020 09:31:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="AenMzpFa" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727804AbgK3Jav (ORCPT ); Mon, 30 Nov 2020 04:30:51 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57356 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727628AbgK3Jav (ORCPT ); Mon, 30 Nov 2020 04:30:51 -0500 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2C8C4C0613CF; Mon, 30 Nov 2020 01:30:10 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.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=Qm+mEK06jeIylWH4CfquOTPlX9S20bRHRY0l3x6+Qik=; b=AenMzpFaJkqNGAxuS8hKwAiMgA 4ISTolEMS6eong2QZUaJjw2leQiObEK1qwozGsZ4f+nZbatk0DJ2MX5ZWdkZ0Xb9n5e0iQZ+gVZVf eduxONkowfOwtFnYMslTOdP38vvcJ+wHngenPmoWUE5LACtwPElVRB3eJHFvkLEtmeX64ZILYX2fs eHv2D5HfAxa5r8rZV4MPuyD5rfqFkGcfBTfvefdL52q0ZeC3nQk3fC50qcXi8GxYh8O+orGpTG+QN 8MQjbdH3TcGu4sRFR61XMC4uzyQDW4KEW079MA7FTJjpU/yJLSwla0Ci/q3yyLpIiK+tKyiKBad2e zcHfSNyg==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1kjfVQ-0007lb-Ue; Mon, 30 Nov 2020 09:30:01 +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 3B1F9305815; Mon, 30 Nov 2020 10:30:00 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 26073203EEFB6; Mon, 30 Nov 2020 10:30:00 +0100 (CET) Date: Mon, 30 Nov 2020 10:30:00 +0100 From: Peter Zijlstra To: Andy Lutomirski Cc: Nicholas Piggin , LKML , X86 ML , Mathieu Desnoyers , Arnd Bergmann , linux-arch , linuxppc-dev , Linux-MM , Anton Blanchard Subject: Re: [PATCH 6/8] lazy tlb: shoot lazies, a non-refcounting lazy tlb option Message-ID: <20201130093000.GM2414@hirez.programming.kicks-ass.net> References: <20201128160141.1003903-1-npiggin@gmail.com> <20201128160141.1003903-7-npiggin@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-arch@vger.kernel.org On Sat, Nov 28, 2020 at 07:54:57PM -0800, Andy Lutomirski wrote: > This means that mm_cpumask operations won't need to be full barriers > forever, and we might not want to take the implied full barriers in > set_bit() and clear_bit() for granted. There is no implied full barrier for those ops.