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=-23.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_IN_DEF_DKIM_WL 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 9CF3CC47084 for ; Mon, 24 May 2021 05:17:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7022F60D07 for ; Mon, 24 May 2021 05:17:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232230AbhEXFRr (ORCPT ); Mon, 24 May 2021 01:17:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49032 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229564AbhEXFRo (ORCPT ); Mon, 24 May 2021 01:17:44 -0400 Received: from mail-pl1-x62f.google.com (mail-pl1-x62f.google.com [IPv6:2607:f8b0:4864:20::62f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A430CC061574 for ; Sun, 23 May 2021 22:16:14 -0700 (PDT) Received: by mail-pl1-x62f.google.com with SMTP id s4so12480223plg.12 for ; Sun, 23 May 2021 22:16:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:in-reply-to:message-id:references :mime-version; bh=rxCIp0pv5uzxsSEr1xQGI8fGMXNRFQKrxxPclrqJINI=; b=H3T5RdUbHndkki97jgA4nVhBjEEWQyyfl7aVBK/d6D/yOdmpLQF+fMLzYcO+qLubJ4 LEOkZQ92FgX5WhfORD6urCVyafvdN0YtcTpjWXXoHeHckZ1d1ieihz/t5B+IXf5oCa8b b9SwjEViYuvKfqPDPYIarML/8XnHzDHHEwgjncNAlyQQrBOVA3cv9bQAGwHO5zIiuEEJ YsnntP1oVrCMGURYe7nPaOM8bQ0n3fQ7yUya/rCt1p5HWIX3/aDWMV7gyknsWrSrKxxK 0oVsofKonccvP/w+iozzVOxYU16aPFAy2DoWL94W3Zm2dUzLsfmGr3+/0/eMkfhZ4AYo O5Ng== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:in-reply-to:message-id :references:mime-version; bh=rxCIp0pv5uzxsSEr1xQGI8fGMXNRFQKrxxPclrqJINI=; b=bUymnHwqO8Zy7Nd5LgNSTgrT80mTDEoh5TV1/B1rUeIJwzRF18pdV4sAFMuk7cZ5Q5 LdCh4w4xTup+pdzOLQGDN0+9MGFuQmAS24u1f5TNhq8iw5S8OZWEbNpIc/TWRqDR/yRf bB92CPBdVZstwGRGPMxyLNLMcEjh8hGHHh3bGwpssYijmI97opHk2d9xPwI7cC+bdND6 jaoplkxPtgMXo/UPDM4Iai8uvAhvIHiq6+jpQOglxM1CamG9kGFtCol3ndTBQYA3emvH k9h3sAbpz4WOlF2p0XNDF4LKgLL/dfNlLUnj49ULAbo4yllbAYCR/3rDhoK7AtCvfmLP ixrw== X-Gm-Message-State: AOAM532kLgqCNXCJRTT9Fw0Cbo3uxLnvOgmAdh2x3F/SJ3BnhJ6GY342 M/pJy7eq9ZzCLoobKa2Q+MSmvQ== X-Google-Smtp-Source: ABdhPJxRfVirUtpZaiSODig2PF5VCXVnshQE2jz+Nv61ptEy7AEI4urI1Zx8B1y7W0JFTBGptjsZQg== X-Received: by 2002:a17:90b:19d3:: with SMTP id nm19mr23271171pjb.215.1621833373231; Sun, 23 May 2021 22:16:13 -0700 (PDT) Received: from [2620:15c:17:3:9016:8a6d:7de4:aa23] ([2620:15c:17:3:9016:8a6d:7de4:aa23]) by smtp.gmail.com with ESMTPSA id x187sm4511284pfc.104.2021.05.23.22.16.12 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 23 May 2021 22:16:12 -0700 (PDT) Date: Sun, 23 May 2021 22:16:11 -0700 (PDT) From: David Rientjes To: Feng Tang 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 In-Reply-To: <1621499404-67756-3-git-send-email-feng.tang@intel.com> Message-ID: <7a58082-eb68-744c-93b7-1a688b3b27a@google.com> References: <1621499404-67756-1-git-send-email-feng.tang@intel.com> <1621499404-67756-3-git-send-email-feng.tang@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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. > + \ > + 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 > >