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=-2.1 required=3.0 tests=DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,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 42078C433F4 for ; Sat, 22 Sep 2018 10:38:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E0FA521522 for ; Sat, 22 Sep 2018 10:38:00 +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="cPSGy2df" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E0FA521522 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.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 S1728445AbeIVQbE (ORCPT ); Sat, 22 Sep 2018 12:31:04 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:56860 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726004AbeIVQbE (ORCPT ); Sat, 22 Sep 2018 12:31:04 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.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:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=qAv5cwmvc7TyPUSwOapzr0g1vq0NOqMFuJwbTvOo8Lk=; b=cPSGy2dfPQAIiPm8k2I7CK9Wk VFSkAGd2eDMXYg86ncbOg8gWl89eshiRnbkFEgSTcYgc4XsljuesIocdF/Gp1JmyAWNXJ2Z6mnYtg zwIjl4CAxRMWyLOK+vbbOuiuRXKHmEKvstMWkL0rywj/V1yXi4EOxSwjcwRCoeqP9rZ0fGqzwzNJg YgnjxCrvN//ZV6IeHEzSvPOyoNErT5Z53dBR0mfPYV7H6NEVHrmONk9wLb8StsbBK93vMvi27H6U5 HgV6pfPluGLTqwfyllkwX9aqpIsUgDLCadMKyxxroMTyc2bvvyirCAmQtTD3B5ZTj3v0aJXfYcsSB CrH0/qgaw==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by bombadil.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1g3fIS-0000Ej-Dc; Sat, 22 Sep 2018 10:37:56 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id CF6652025483B; Sat, 22 Sep 2018 12:37:52 +0200 (CEST) Date: Sat, 22 Sep 2018 12:37:52 +0200 From: Peter Zijlstra To: Dave Hansen Cc: Thomas Gleixner , linux-kernel@vger.kernel.org, x86@kernel.org, Bin Yang , Mark Gross Subject: Re: [PATCH 2/8] x86/mm/cpa: Move flush_tlb_all() Message-ID: <20180922103752.GI24124@hirez.programming.kicks-ass.net> References: <20180919085016.164552924@infradead.org> <20180919085947.882287392@infradead.org> <5ab3ee67-a29b-0f4c-d7cf-2bdedd192ad6@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5ab3ee67-a29b-0f4c-d7cf-2bdedd192ad6@intel.com> User-Agent: Mutt/1.10.0 (2018-05-17) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Sep 21, 2018 at 02:34:32PM -0700, Dave Hansen wrote: > On 09/19/2018 01:50 AM, Peter Zijlstra wrote: > > @@ -1528,28 +1538,8 @@ static int __change_page_attr(struct cpa > > * We have to split the large page: > > */ > > err = split_large_page(cpa, kpte, address); > > - if (!err) { > ... > > - flush_tlb_all(); > > + if (!err) > > goto repeat; > > - } > > I _think_ this is the only use of split_large_page()'s error code. We > can just make it return void now, right? Then how does it decide to goto repeat or error out? > BTW, I also really like doing the "final" TLB flush as close as possible > to the actual PTE manipulation. Makes it much less likely that we break it. Yes.