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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 A04CBECE58E for ; Mon, 7 Oct 2019 15:48:59 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 7020220679 for ; Mon, 7 Oct 2019 15:48:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7020220679 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 17CF58E0005; Mon, 7 Oct 2019 11:48:59 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 12E3D8E0003; Mon, 7 Oct 2019 11:48:59 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 042718E0005; Mon, 7 Oct 2019 11:48:58 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0182.hostedemail.com [216.40.44.182]) by kanga.kvack.org (Postfix) with ESMTP id D0D8C8E0003 for ; Mon, 7 Oct 2019 11:48:58 -0400 (EDT) Received: from smtpin03.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with SMTP id 77DD84425 for ; Mon, 7 Oct 2019 15:48:58 +0000 (UTC) X-FDA: 76017421956.03.key65_313131dc8a408 X-HE-Tag: key65_313131dc8a408 X-Filterd-Recvd-Size: 2602 Received: from mx1.suse.de (mx2.suse.de [195.135.220.15]) by imf05.hostedemail.com (Postfix) with ESMTP for ; Mon, 7 Oct 2019 15:48:57 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 7889CAFBE; Mon, 7 Oct 2019 15:48:56 +0000 (UTC) Date: Mon, 7 Oct 2019 17:48:52 +0200 From: Joerg Roedel To: Dave Hansen Cc: Joerg Roedel , Dave Hansen , Andy Lutomirski , Peter Zijlstra , Thomas Gleixner , Ingo Molnar , Borislav Petkov , hpa@zytor.com, x86@kernel.org, rjw@rjwysocki.net, lenb@kernel.org, james.morse@arm.com, tony.luck@intel.com, linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH] x86/mm: Split vmalloc_sync_all() Message-ID: <20191007154852.GE4636@suse.de> References: <20191007151618.11785-1-joro@8bytes.org> <02e99987-10d2-203f-e6ba-e2568fa1af28@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <02e99987-10d2-203f-e6ba-e2568fa1af28@intel.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Hi Dave, thanks for your review! On Mon, Oct 07, 2019 at 08:30:51AM -0700, Dave Hansen wrote: > On 10/7/19 8:16 AM, Joerg Roedel wrote: > > @@ -318,7 +328,7 @@ static void dump_pagetable(unsigned long address) > > > > #else /* CONFIG_X86_64: */ > > > > -void vmalloc_sync_all(void) > > +void vmalloc_sync_mappings(void) > > { > > sync_global_pgds(VMALLOC_START & PGDIR_MASK, VMALLOC_END); > > } > > FWIW, I generally detest the use of __weak. :) Yeah, I don't like it either, but in this case it is probably better than empty stubs in all architectures besides x86 :) > In this case, it ends up letting us gloss over the fact that we have a > 32/64-bit asymmetry. It would probably be nice to actually have a > 64-bit implementation that comes along with a nice comment. Maybe this > in vmalloc_sync_mappings(): > > /* > * 64-bit mappings might allocate new p4d/pud pages > * that need to be propagated to all tasks' PGDs. > */ > > which would pair nicely with: > > void vmalloc_sync_unmappings(void) > { > /* > * Unmappings never allocate or free p4d/pud pages. > * No work is required here. > */ > } Yes, that makes, I will add these comments in V2. Thanks, Joerg