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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS 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 EB4ECC43441 for ; Fri, 9 Nov 2018 11:33:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BBDB920883 for ; Fri, 9 Nov 2018 11:33:12 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BBDB920883 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728390AbeKIVNY (ORCPT ); Fri, 9 Nov 2018 16:13:24 -0500 Received: from foss.arm.com ([217.140.101.70]:57764 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727596AbeKIVNX (ORCPT ); Fri, 9 Nov 2018 16:13:23 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id B8B8480D; Fri, 9 Nov 2018 03:33:10 -0800 (PST) Received: from [10.162.0.72] (p8cg001049571a15.blr.arm.com [10.162.0.72]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 6747D3F718; Fri, 9 Nov 2018 03:33:08 -0800 (PST) Subject: Re: [RFC][PATCH v1 11/11] mm: hwpoison: introduce clear_hwpoison_free_buddy_page() To: Naoya Horiguchi , linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: Michal Hocko , Andrew Morton , Mike Kravetz , xishi.qiuxishi@alibaba-inc.com, Laurent Dufour References: <1541746035-13408-1-git-send-email-n-horiguchi@ah.jp.nec.com> <1541746035-13408-12-git-send-email-n-horiguchi@ah.jp.nec.com> From: Anshuman Khandual Message-ID: Date: Fri, 9 Nov 2018 17:03:06 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <1541746035-13408-12-git-send-email-n-horiguchi@ah.jp.nec.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/09/2018 12:17 PM, Naoya Horiguchi wrote: > The new function is a reverse operation of set_hwpoison_free_buddy_page() > to adjust unpoison_memory() to the new semantics. > > Signed-off-by: Naoya Horiguchi snip > + > +/* > + * Reverse operation of set_hwpoison_free_buddy_page(), which is expected > + * to work only on error pages isolated from buddy allocator. > + */ > +bool clear_hwpoison_free_buddy_page(struct page *page) > +{ > + struct zone *zone = page_zone(page); > + bool unpoisoned = false; > + > + spin_lock(&zone->lock); > + if (TestClearPageHWPoison(page)) { > + unsigned long pfn = page_to_pfn(page); > + int migratetype = get_pfnblock_migratetype(page, pfn); > + > + __free_one_page(page, pfn, zone, 0, migratetype); > + unpoisoned = true; > + } > + spin_unlock(&zone->lock); > + return unpoisoned; > +} > #endif > Though there are multiple page state checks in unpoison_memory() leading upto clearing HWPoison flag, the page must not be in buddy already if __free_one_page() would be called on it.