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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,UNPARSEABLE_RELAY, URIBL_BLOCKED,USER_AGENT_GIT 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 CF33BC43381 for ; Wed, 20 Mar 2019 00:27:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A89432175B for ; Wed, 20 Mar 2019 00:27:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727274AbfCTA1w (ORCPT ); Tue, 19 Mar 2019 20:27:52 -0400 Received: from out30-42.freemail.mail.aliyun.com ([115.124.30.42]:42483 "EHLO out30-42.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726801AbfCTA1v (ORCPT ); Tue, 19 Mar 2019 20:27:51 -0400 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R561e4;CH=green;DM=||false|;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01f04452;MF=yang.shi@linux.alibaba.com;NM=1;PH=DS;RN=7;SR=0;TI=SMTPD_---0TN9thOz_1553041659; Received: from e19h19392.et15sqa.tbsite.net(mailfrom:yang.shi@linux.alibaba.com fp:SMTPD_---0TN9thOz_1553041659) by smtp.aliyun-inc.com(127.0.0.1); Wed, 20 Mar 2019 08:27:45 +0800 From: Yang Shi To: mgorman@techsingularity.net, mhocko@suse.com, vbabka@suse.cz, akpm@linux-foundation.org Cc: yang.shi@linux.alibaba.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [RFC PATCH] mm: mempolicy: remove MPOL_MF_LAZY Date: Wed, 20 Mar 2019 08:27:39 +0800 Message-Id: <1553041659-46787-1-git-send-email-yang.shi@linux.alibaba.com> X-Mailer: git-send-email 1.8.3.1 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org MPOL_MF_LAZY was added by commit b24f53a0bea3 ("mm: mempolicy: Add MPOL_MF_LAZY"), then it was disabled by commit a720094ded8c ("mm: mempolicy: Hide MPOL_NOOP and MPOL_MF_LAZY from userspace for now") right away in 2012. So, it is never ever exported to userspace. And, it looks nobody is interested in revisiting it since it was disabled 7 years ago. So, it sounds pointless to still keep it around. Cc: Mel Gorman Cc: Michal Hocko Cc: Vlastimil Babka Signed-off-by: Yang Shi --- Hi folks, I'm not sure if you still would like to revisit it later. And, I may be not the first one to try to remvoe it. IMHO, it sounds pointless to still keep it around if nobody is interested in it. include/uapi/linux/mempolicy.h | 3 +-- mm/mempolicy.c | 13 ------------- 2 files changed, 1 insertion(+), 15 deletions(-) diff --git a/include/uapi/linux/mempolicy.h b/include/uapi/linux/mempolicy.h index 3354774..eb52a7a 100644 --- a/include/uapi/linux/mempolicy.h +++ b/include/uapi/linux/mempolicy.h @@ -45,8 +45,7 @@ enum { #define MPOL_MF_MOVE (1<<1) /* Move pages owned by this process to conform to policy */ #define MPOL_MF_MOVE_ALL (1<<2) /* Move every page to conform to policy */ -#define MPOL_MF_LAZY (1<<3) /* Modifies '_MOVE: lazy migrate on fault */ -#define MPOL_MF_INTERNAL (1<<4) /* Internal flags start here */ +#define MPOL_MF_INTERNAL (1<<3) /* Internal flags start here */ #define MPOL_MF_VALID (MPOL_MF_STRICT | \ MPOL_MF_MOVE | \ diff --git a/mm/mempolicy.c b/mm/mempolicy.c index af171cc..67886f4 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -593,15 +593,6 @@ static int queue_pages_test_walk(unsigned long start, unsigned long end, qp->prev = vma; - if (flags & MPOL_MF_LAZY) { - /* Similar to task_numa_work, skip inaccessible VMAs */ - if (!is_vm_hugetlb_page(vma) && - (vma->vm_flags & (VM_READ | VM_EXEC | VM_WRITE)) && - !(vma->vm_flags & VM_MIXEDMAP)) - change_prot_numa(vma, start, endvma); - return 1; - } - /* queue pages from current vma */ if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) return 0; @@ -1181,9 +1172,6 @@ static long do_mbind(unsigned long start, unsigned long len, if (IS_ERR(new)) return PTR_ERR(new); - if (flags & MPOL_MF_LAZY) - new->flags |= MPOL_F_MOF; - /* * If we are using the default policy then operation * on discontinuous address spaces is okay after all @@ -1226,7 +1214,6 @@ static long do_mbind(unsigned long start, unsigned long len, int nr_failed = 0; if (!list_empty(&pagelist)) { - WARN_ON_ONCE(flags & MPOL_MF_LAZY); nr_failed = migrate_pages(&pagelist, new_page, NULL, start, MIGRATE_SYNC, MR_MEMPOLICY_MBIND); if (nr_failed) -- 1.8.3.1