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=-9.6 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_GIT 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 7D442C4360C for ; Thu, 10 Oct 2019 13:41:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4FD352067B for ; Thu, 10 Oct 2019 13:41:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=shipmail.org header.i=@shipmail.org header.b="ijWXaZYo" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388236AbfJJNlX (ORCPT ); Thu, 10 Oct 2019 09:41:23 -0400 Received: from ste-pvt-msa1.bahnhof.se ([213.80.101.70]:23236 "EHLO ste-pvt-msa1.bahnhof.se" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728100AbfJJNlV (ORCPT ); Thu, 10 Oct 2019 09:41:21 -0400 Received: from localhost (localhost [127.0.0.1]) by ste-pvt-msa1.bahnhof.se (Postfix) with ESMTP id 5038F3F662; Thu, 10 Oct 2019 15:41:19 +0200 (CEST) Authentication-Results: ste-pvt-msa1.bahnhof.se; dkim=pass (1024-bit key; unprotected) header.d=shipmail.org header.i=@shipmail.org header.b=ijWXaZYo; dkim-atps=neutral X-Virus-Scanned: Debian amavisd-new at bahnhof.se Received: from ste-pvt-msa1.bahnhof.se ([127.0.0.1]) by localhost (ste-pvt-msa1.bahnhof.se [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id JuFPudYhk_3z; Thu, 10 Oct 2019 15:41:18 +0200 (CEST) Received: from mail1.shipmail.org (h-205-35.A357.priv.bahnhof.se [155.4.205.35]) (Authenticated sender: mb878879) by ste-pvt-msa1.bahnhof.se (Postfix) with ESMTPA id EBF0D3F247; Thu, 10 Oct 2019 15:41:17 +0200 (CEST) Received: from localhost.localdomain.localdomain (h-205-35.A357.priv.bahnhof.se [155.4.205.35]) by mail1.shipmail.org (Postfix) with ESMTPSA id 2C952360ED5; Thu, 10 Oct 2019 15:41:17 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=shipmail.org; s=mail; t=1570714877; bh=xEUu8V1jmdy0b1JnfsdE1ixgai5iPm/a0UL1Js6USpk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ijWXaZYo+2T/KF/TFThEJ4/Jb8vCSvNjD316eFCovtyF5dIhD6is1nn8Kn78Yp1wl 109pQPDHWw2KQATIc41ioJqlpOP16P7BQjGrKD72PtUYMLh1D9cydzTUygDh0D4Xbp cSmgxlrMIlSAK3nmcoPyIrQVjCSCd17RHCyvyuIs= From: =?UTF-8?q?Thomas=20Hellstr=C3=B6m=20=28VMware=29?= To: linux-kernel@vger.kernel.org, linux-mm@kvack.org, torvalds@linux-foundation.org, kirill@shutemov.name Cc: Thomas Hellstrom Subject: [RFC PATCH 1/4] mm: Have the mempolicy pagewalk to avoid positive callback return codes Date: Thu, 10 Oct 2019 15:40:55 +0200 Message-Id: <20191010134058.11949-2-thomas_os@shipmail.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20191010134058.11949-1-thomas_os@shipmail.org> References: <20191010134058.11949-1-thomas_os@shipmail.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Linus Torvalds The pagewalk code is being reworked to have positive callback return codes do walk control. Avoid using positive return codes: "1" is replaced by "-EBUSY". Co-developed-by: Thomas Hellstrom Signed-off-by: Thomas Hellstrom --- mm/mempolicy.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 4ae967bcf954..df34c7498c27 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -482,8 +482,8 @@ static int queue_pages_pmd(pmd_t *pmd, spinlock_t *ptl, unsigned long addr, * * queue_pages_pte_range() has three possible return values: * 0 - pages are placed on the right node or queued successfully. - * 1 - there is unmovable page, and MPOL_MF_MOVE* & MPOL_MF_STRICT were - * specified. + * -EBUSY - there is unmovable page, and MPOL_MF_MOVE* & MPOL_MF_STRICT were + * specified. * -EIO - only MPOL_MF_STRICT was specified and an existing page was already * on a node that does not follow the policy. */ @@ -503,7 +503,7 @@ static int queue_pages_pte_range(pmd_t *pmd, unsigned long addr, if (ptl) { ret = queue_pages_pmd(pmd, ptl, addr, end, walk); if (ret != 2) - return ret; + return (ret == 1) ? -EBUSY : ret; } /* THP was split, fall through to pte walk */ @@ -546,7 +546,7 @@ static int queue_pages_pte_range(pmd_t *pmd, unsigned long addr, cond_resched(); if (has_unmovable) - return 1; + return -EBUSY; return addr != end ? -EIO : 0; } @@ -669,9 +669,9 @@ static const struct mm_walk_ops queue_pages_walk_ops = { * passed via @private. * * queue_pages_range() has three possible return values: - * 1 - there is unmovable page, but MPOL_MF_MOVE* & MPOL_MF_STRICT were - * specified. * 0 - queue pages successfully or no misplaced page. + * -EBUSY - there is unmovable page, but MPOL_MF_MOVE* & MPOL_MF_STRICT were + * specified. * -EIO - there is misplaced page and only MPOL_MF_STRICT was specified. */ static int @@ -1285,7 +1285,7 @@ static long do_mbind(unsigned long start, unsigned long len, ret = queue_pages_range(mm, start, end, nmask, flags | MPOL_MF_INVERT, &pagelist); - if (ret < 0) { + if (ret < 0 && ret != -EBUSY) { err = -EIO; goto up_out; } @@ -1303,7 +1303,7 @@ static long do_mbind(unsigned long start, unsigned long len, putback_movable_pages(&pagelist); } - if ((ret > 0) || (nr_failed && (flags & MPOL_MF_STRICT))) + if ((ret < 0) || (nr_failed && (flags & MPOL_MF_STRICT))) err = -EIO; } else putback_movable_pages(&pagelist); -- 2.21.0