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=-8.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 6093EC43331 for ; Sun, 29 Mar 2020 16:05:28 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 10FD42073B for ; Sun, 29 Mar 2020 16:05:27 +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="l1WgTAtH" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 10FD42073B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=alum.mit.edu Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 82EED6B0010; Sun, 29 Mar 2020 12:05:27 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 7B8356B0032; Sun, 29 Mar 2020 12:05:27 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 658CE6B0036; Sun, 29 Mar 2020 12:05:27 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0142.hostedemail.com [216.40.44.142]) by kanga.kvack.org (Postfix) with ESMTP id 482766B0010 for ; Sun, 29 Mar 2020 12:05:27 -0400 (EDT) Received: from smtpin19.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 0E5F8180AE31D for ; Sun, 29 Mar 2020 16:05:27 +0000 (UTC) X-FDA: 76648874694.19.hat09_3fc953015b2d Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin19.hostedemail.com (Postfix) with ESMTP id B5D6C4F4AD for ; Sun, 29 Mar 2020 15:00:27 +0000 (UTC) X-HE-Tag: hat09_3fc953015b2d X-Filterd-Recvd-Size: 6767 Received: from mail-qv1-f66.google.com (mail-qv1-f66.google.com [209.85.219.66]) by imf27.hostedemail.com (Postfix) with ESMTP for ; Sun, 29 Mar 2020 15:00:27 +0000 (UTC) Received: by mail-qv1-f66.google.com with SMTP id bp12so3569124qvb.7 for ; Sun, 29 Mar 2020 08:00:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:from:date:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=rGYXAWrsWIiLxM6vPsIDZ7Rl8wO5mf18IjFe9bRFrdY=; b=l1WgTAtHA2qzsTMjg9bSRxPYSmVkj+ocQcmwqNeUWqzZT2PrDU2wmSkTOXNlk8pnSd Ke7q89sT/A+PdbS//C2wAsaMuxtRZtlrDcy8IL4pNhieSbhK23liAHwCIhCZtvInOXnS u3UqZr/0kItiLH3hsZdHySOupM06YTyY5KhWD/OHjdAufCynTaCvMhOHwgFxv84hroTa 9nKqcuSGBUXYSNZQkY/8FyLK6SbjbQjcyOCxdBiqBErl6VnKiQhm9uZibZA/VBzP28mJ QZSlwbziG0QbzcDWqjM8FI7mzOBKdxqqFc061tjkiYsS38AUSYvSl1mbnwQ5qen9bfbO itpw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:date:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to:user-agent; bh=rGYXAWrsWIiLxM6vPsIDZ7Rl8wO5mf18IjFe9bRFrdY=; b=BH91gg4s0zVBK5Dgv7KDziZHDyjfg8MhK/vImQoreDnZnf3HRwSisAN+KaA+Q2DqAm JGB+BNchAMcPWsEhMi+oxrJP+L7pqR9xKqcmwHThZ2D25kYWn4VqnqWKgAdP8ouq+5uQ TqZy3Q4Ke/OKIngvSsZv578Wph+61/F4qCZQ8J1VXDZzU0I5iWRgubij+5w7FFn/bahe z0pq3RCgcbYxkuDjxamcgTp8DreUUcOfTnC3AV7Mqjf/nM9hJGtI7d1QcTHQqgWMPIoO GPBJPv0hQIkOofAceAS217gP2W+sJPgYN/vFeeB+rPxyGvjkG4Nrs3Z0FuPECx+M5jsP PlSg== X-Gm-Message-State: ANhLgQ2AgB4IIVX34SzsXBU2sDWDvR6q6LTEtaxuIWaSBs/tuBB5kCBT N24EKCy/hqv4+QyzPtXmnzg= X-Google-Smtp-Source: ADFU+vtYT62GFNGeoVetw+nZmaRphF0bJ+n5GbMC9MYWFGp7A0ljCgjR4ff4KGTtPm64IJAKsM79Iw== X-Received: by 2002:ad4:4364:: with SMTP id u4mr7593136qvt.58.1585494026561; Sun, 29 Mar 2020 08:00:26 -0700 (PDT) Received: from rani.riverdale.lan ([2001:470:1f07:5f3::b55f]) by smtp.gmail.com with ESMTPSA id l62sm5281385qte.52.2020.03.29.08.00.25 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 29 Mar 2020 08:00:26 -0700 (PDT) From: Arvind Sankar X-Google-Original-From: Arvind Sankar Date: Sun, 29 Mar 2020 11:00:24 -0400 To: Vlastimil Babka Cc: Luis Chamberlain , Kees Cook , Iurii Zaikin , linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, linux-mm@kvack.org, Ivan Teterevkov , Michal Hocko , David Rientjes , Matthew Wilcox , "Eric W . Biederman" , "Guilherme G . Piccoli" Subject: Re: [RFC v2 2/2] kernel/sysctl: support handling command line aliases Message-ID: <20200329150022.GA823603@rani.riverdale.lan> References: <20200325120345.12946-1-vbabka@suse.cz> <20200325120345.12946-2-vbabka@suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20200325120345.12946-2-vbabka@suse.cz> 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: On Wed, Mar 25, 2020 at 01:03:45PM +0100, Vlastimil Babka wrote: > We can now handle sysctl parameters on kernel command line, but historically > some parameters introduced their own command line equivalent, which we don't > want to remove for compatibility reasons. We can however convert them to the > generic infrastructure with a table translating the legacy command line > parameters to their sysctl names, and removing the one-off param handlers. > > This patch adds the support and makes the first conversion to demonstrate it, > on the (deprecated) numa_zonelist_order parameter. > > Signed-off-by: Vlastimil Babka > --- > kernel/sysctl.c | 39 +++++++++++++++++++++++++++++++++++---- > mm/page_alloc.c | 9 --------- > 2 files changed, 35 insertions(+), 13 deletions(-) > > diff --git a/kernel/sysctl.c b/kernel/sysctl.c > index 18c7f5606d55..fd72853396f9 100644 > --- a/kernel/sysctl.c > +++ b/kernel/sysctl.c > @@ -1971,6 +1971,22 @@ static struct ctl_table dev_table[] = { > { } > }; > > +struct sysctl_alias { > + char *kernel_param; > + char *sysctl_param; > +}; > + > +/* > + * Historically some settings had both sysctl and a command line parameter. > + * With the generic sysctl. parameter support, we can handle them at a single > + * place and only keep the historical name for compatibility. This is not meant > + * to add brand new aliases. > + */ > +static struct sysctl_alias sysctl_aliases[] = { > + {"numa_zonelist_order", "vm.numa_zonelist_order" }, > + { } > +}; > + > int __init sysctl_init(void) > { > struct ctl_table_header *hdr; > @@ -1980,6 +1996,18 @@ int __init sysctl_init(void) > return 0; > } > > +char *sysctl_find_alias(char *param) This function should probably be declared static? > +{ > + struct sysctl_alias *alias; > + > + for (alias = &sysctl_aliases[0]; alias->kernel_param != NULL; alias++) { > + if (strcmp(alias->kernel_param, param) == 0) > + return alias->sysctl_param; > + } > + > + return NULL; > +} > + > /* Set sysctl value passed on kernel command line. */ > int process_sysctl_arg(char *param, char *val, > const char *unused, void *arg) > @@ -1990,10 +2018,13 @@ int process_sysctl_arg(char *param, char *val, > loff_t ppos = 0; > struct ctl_table *ctl, *found = NULL; > > - if (strncmp(param, "sysctl.", sizeof("sysctl.") - 1)) > - return 0; > - > - param += sizeof("sysctl.") - 1; > + if (strncmp(param, "sysctl.", sizeof("sysctl.") - 1) == 0) { > + param += sizeof("sysctl.") - 1; > + } else { > + param = sysctl_find_alias(param); > + if (!param) > + return 0; > + } > > remaining = param; > ctl = &sysctl_base_table[0]; > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index 3c4eb750a199..de7a134b1b8a 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -5460,15 +5460,6 @@ static int __parse_numa_zonelist_order(char *s) > return 0; > } > > -static __init int setup_numa_zonelist_order(char *s) > -{ > - if (!s) > - return 0; > - > - return __parse_numa_zonelist_order(s); > -} > -early_param("numa_zonelist_order", setup_numa_zonelist_order); > - > char numa_zonelist_order[] = "Node"; > > /* > -- > 2.25.1 >