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=-15.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 17284C04FF3 for ; Mon, 24 May 2021 05:59:47 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 74826610A6 for ; Mon, 24 May 2021 05:59:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 74826610A6 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 0239594004B; Mon, 24 May 2021 01:59:46 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id EEFBB940042; Mon, 24 May 2021 01:59:45 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D1AB494004B; Mon, 24 May 2021 01:59:45 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0251.hostedemail.com [216.40.44.251]) by kanga.kvack.org (Postfix) with ESMTP id 9BAB4940042 for ; Mon, 24 May 2021 01:59:45 -0400 (EDT) Received: from smtpin21.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 1405B8249980 for ; Mon, 24 May 2021 05:59:45 +0000 (UTC) X-FDA: 78175073130.21.D0D76F9 Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by imf22.hostedemail.com (Postfix) with ESMTP id 96B26C0042E1 for ; Mon, 24 May 2021 05:59:39 +0000 (UTC) IronPort-SDR: MjztQ/sfhOkj6+9IdMXaGxzMt6gyOH+VoyBO4SQDUGUJre3ybCtGPLXHy16ykaAsIJWXkVGG3i uH6f+sx5mJ3w== X-IronPort-AV: E=McAfee;i="6200,9189,9993"; a="223014075" X-IronPort-AV: E=Sophos;i="5.82,319,1613462400"; d="scan'208";a="223014075" Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 May 2021 22:59:43 -0700 IronPort-SDR: rB0cJg0zNoe7UcxKKtzFqnieMtgeEvNXAV1KYWXiZILMuNvfxJadrLmpqlhbLOo01pxRbRUcJ/ fh6vzNWcDGLg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.82,319,1613462400"; d="scan'208";a="545735360" Received: from shbuild999.sh.intel.com (HELO localhost) ([10.239.147.94]) by fmsmga001.fm.intel.com with ESMTP; 23 May 2021 22:59:39 -0700 Date: Mon, 24 May 2021 13:59:39 +0800 From: Feng Tang To: David Rientjes Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrew Morton , Michal Hocko , Andrea Arcangeli , Mel Gorman , Mike Kravetz , Randy Dunlap , Vlastimil Babka , Dave Hansen , Ben Widawsky , Andi Kleen , Dan Williams , ying.huang@intel.com Subject: Re: [RFC Patch v2 2/4] mm/mempolicy: unify the preprocessing for mbind and set_mempolicy Message-ID: <20210524055939.GB48704@shbuild999.sh.intel.com> References: <1621499404-67756-1-git-send-email-feng.tang@intel.com> <1621499404-67756-3-git-send-email-feng.tang@intel.com> <7a58082-eb68-744c-93b7-1a688b3b27a@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <7a58082-eb68-744c-93b7-1a688b3b27a@google.com> User-Agent: Mutt/1.5.24 (2015-08-30) Authentication-Results: imf22.hostedemail.com; dkim=none; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=intel.com (policy=none); spf=none (imf22.hostedemail.com: domain of feng.tang@intel.com has no SPF policy when checking 192.55.52.88) smtp.mailfrom=feng.tang@intel.com X-Stat-Signature: jd173yqkuai84weyg4rccbg46zm8eu7h X-Rspamd-Queue-Id: 96B26C0042E1 X-Rspamd-Server: rspam02 X-HE-Tag: 1621835979-615900 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 Sun, May 23, 2021 at 10:16:11PM -0700, David Rientjes wrote: > On Thu, 20 May 2021, Feng Tang wrote: > > > Currently the kernel_mbind() and kernel_set_mempolicy() do almost > > the same operation for parameter sanity check and preprocessing. > > > > Add a macro to unify the code to reduce the redundancy, and make > > it easier for changing the pre-processing code in future. > > > > Signed-off-by: Feng Tang > > --- > > mm/mempolicy.c | 46 +++++++++++++++++++--------------------------- > > 1 file changed, 19 insertions(+), 27 deletions(-) > > > > diff --git a/mm/mempolicy.c b/mm/mempolicy.c > > index 1964cca..0f5bf60 100644 > > --- a/mm/mempolicy.c > > +++ b/mm/mempolicy.c > > @@ -1460,25 +1460,29 @@ static int copy_nodes_to_user(unsigned long __user *mask, unsigned long maxnode, > > return copy_to_user(mask, nodes_addr(*nodes), copy) ? -EFAULT : 0; > > } > > > > +#define MPOL_PRE_PROCESS() \ > > This should be extracted to helper function returning bool, not a macro. Yes, initially I did try it with an inline function, but as a function it has quite several input parameters and several output parameters, which made the code still big and ugly. But if community think it's the right direction to go, I can change it. Thanks, Feng > > + \ > > + nodemask_t nodes; \ > > + int err; \ > > + unsigned short mode_flags; \ > > + mode_flags = mode & MPOL_MODE_FLAGS; \ > > + mode &= ~MPOL_MODE_FLAGS; \ > > + if (mode >= MPOL_MAX) \ > > + return -EINVAL; \ > > + if ((mode_flags & MPOL_F_STATIC_NODES) && \ > > + (mode_flags & MPOL_F_RELATIVE_NODES)) \ > > + return -EINVAL; \ > > + err = get_nodes(&nodes, nmask, maxnode); \ > > + if (err) \ > > + return err; > > + > > static long kernel_mbind(unsigned long start, unsigned long len, > > unsigned long mode, const unsigned long __user *nmask, > > unsigned long maxnode, unsigned int flags) > > { > > - nodemask_t nodes; > > - int err; > > - unsigned short mode_flags; > > + MPOL_PRE_PROCESS(); > > > > start = untagged_addr(start); > > - mode_flags = mode & MPOL_MODE_FLAGS; > > - mode &= ~MPOL_MODE_FLAGS; > > - if (mode >= MPOL_MAX) > > - return -EINVAL; > > - if ((mode_flags & MPOL_F_STATIC_NODES) && > > - (mode_flags & MPOL_F_RELATIVE_NODES)) > > - return -EINVAL; > > - err = get_nodes(&nodes, nmask, maxnode); > > - if (err) > > - return err; > > return do_mbind(start, len, mode, mode_flags, &nodes, flags); > > } > > > > @@ -1493,20 +1497,8 @@ SYSCALL_DEFINE6(mbind, unsigned long, start, unsigned long, len, > > static long kernel_set_mempolicy(int mode, const unsigned long __user *nmask, > > unsigned long maxnode) > > { > > - int err; > > - nodemask_t nodes; > > - unsigned short flags; > > - > > - flags = mode & MPOL_MODE_FLAGS; > > - mode &= ~MPOL_MODE_FLAGS; > > - if ((unsigned int)mode >= MPOL_MAX) > > - return -EINVAL; > > - if ((flags & MPOL_F_STATIC_NODES) && (flags & MPOL_F_RELATIVE_NODES)) > > - return -EINVAL; > > - err = get_nodes(&nodes, nmask, maxnode); > > - if (err) > > - return err; > > - return do_set_mempolicy(mode, flags, &nodes); > > + MPOL_PRE_PROCESS(); > > + return do_set_mempolicy(mode, mode_flags, &nodes); > > } > > > > SYSCALL_DEFINE3(set_mempolicy, int, mode, const unsigned long __user *, nmask, > > -- > > 2.7.4 > > > >