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=-7.1 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 2077BC433E9 for ; Thu, 3 Sep 2020 13:44:07 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 7E1FF2072A for ; Thu, 3 Sep 2020 13:44:06 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=soleen.com header.i=@soleen.com header.b="gT/XthbV" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7E1FF2072A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=soleen.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id DBCC26B0002; Thu, 3 Sep 2020 09:44:05 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id D6F1E6B0003; Thu, 3 Sep 2020 09:44:05 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C837F6B0037; Thu, 3 Sep 2020 09:44:05 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0232.hostedemail.com [216.40.44.232]) by kanga.kvack.org (Postfix) with ESMTP id AE3126B0002 for ; Thu, 3 Sep 2020 09:44:05 -0400 (EDT) Received: from smtpin30.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 5B07E362E for ; Thu, 3 Sep 2020 13:44:05 +0000 (UTC) X-FDA: 77221868850.30.train67_0316eb2270aa Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin30.hostedemail.com (Postfix) with ESMTP id 0CFB1180B3C8E for ; Thu, 3 Sep 2020 13:44:05 +0000 (UTC) X-HE-Tag: train67_0316eb2270aa X-Filterd-Recvd-Size: 4229 Received: from mail-ed1-f67.google.com (mail-ed1-f67.google.com [209.85.208.67]) by imf02.hostedemail.com (Postfix) with ESMTP for ; Thu, 3 Sep 2020 13:44:04 +0000 (UTC) Received: by mail-ed1-f67.google.com with SMTP id a12so2681495eds.13 for ; Thu, 03 Sep 2020 06:44:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=soleen.com; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=XsPnpLathKjXprbkqY+YKBNSJFUri0XqOdwMusVjvXU=; b=gT/XthbVd8CL1/XQCWf2oVysDBfnhEQ2b93QTis/AEooCJw9Ac3pkjj2Sl/rWyMgvZ 0Vyf1iHaeFVj7xVcqYSEEn8LH0GUDNm81bHwVAf011MvPvb34vUAm7476fTz41Ks6r4g c04+FoDx3Zi5UjAxseKWfeLBnfMFmr3gw5/4SIlQYeY1/oMpkdtEL+M1Btf6Plsp3xz0 SaSm3YxrDJPpuG8IwiX1Iw5nkerOknoezzUiLAPOLfCEm6WVBV5NvEvKIdmRFf709593 GlIt9Ut4aXS5TKdKulFyXU1mdTegLQQJc3JXQ4D/KkbT+LOw5OmA5y+BzIFClqeSZMK8 8ljQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=XsPnpLathKjXprbkqY+YKBNSJFUri0XqOdwMusVjvXU=; b=mjJBTVY06Vqgusvtd1iVjIx//Y0XpHR5JllRx3l2kUtyBDZIV8hBmsAuZ3c0xZ6tTL 8YRjoj1NE1yjTsqbCN99A4HW2U9hp12sh/i040EQBQtNHpoO3TkC1/3cKW1FkwKyqx3s Bl14KpD7IAXlLHk5jAe19+uLjd/vykcHPm2TiY5+FrNcRAGEuld6wDuZ3lzqwjEyEjHY 81eK226ru+lBGLyXXtcbTxJJuWsJ/nLtKxuXXwpQNnG59DFAusN8ZzrUPt89Q8NZopH+ AUEbPtJilXMWG9Oh4uvqrXId1lzMCQMlTeeO1PMQo6/gLVowMsJGNZQnwUzr6hwPjuNj yvtg== X-Gm-Message-State: AOAM533u0c2WLtDOfCrnNSdGkLZdcdqLBkZcVN+Pg4aIHJFgJqSZS6qc ew/4dYROjTzOnGas7YbwROIl3cUlLhM62PXKd384Cw== X-Google-Smtp-Source: ABdhPJwHLlMV4LeAnjwm5fA6g1O/lUEdcG7wQTFuZXrfgiz8luar5x9cBzY0V1waO35RDKFjCV2vi/FHzdtLgzYO5tg= X-Received: by 2002:a05:6402:1544:: with SMTP id p4mr2917778edx.346.1599140643210; Thu, 03 Sep 2020 06:44:03 -0700 (PDT) MIME-Version: 1.0 References: <20200901124615.137200-1-pasha.tatashin@soleen.com> <20200903070733.GO4617@dhcp22.suse.cz> In-Reply-To: <20200903070733.GO4617@dhcp22.suse.cz> From: Pavel Tatashin Date: Thu, 3 Sep 2020 09:43:27 -0400 Message-ID: Subject: Re: [PATCH] mm/memory_hotplug: drain per-cpu pages again during memory offline To: Michal Hocko Cc: LKML , Andrew Morton , linux-mm Content-Type: text/plain; charset="UTF-8" X-Rspamd-Queue-Id: 0CFB1180B3C8E X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam04 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: Thanks Michal, I will add your comments. Pasha On Thu, Sep 3, 2020 at 3:07 AM Michal Hocko wrote: > > On Tue 01-09-20 08:46:15, Pavel Tatashin wrote: > [...] > > diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c > > index e9d5ab5d3ca0..d6d54922bfce 100644 > > --- a/mm/memory_hotplug.c > > +++ b/mm/memory_hotplug.c > > @@ -1575,6 +1575,15 @@ static int __ref __offline_pages(unsigned long start_pfn, > > /* check again */ > > ret = walk_system_ram_range(start_pfn, end_pfn - start_pfn, > > NULL, check_pages_isolated_cb); > > + /* > > + * per-cpu pages are drained in start_isolate_page_range, but if > > + * there are still pages that are not free, make sure that we > > + * drain again, because when we isolated range we might > > + * have raced with another thread that was adding pages to > > + * pcp list. > > I would also add > * Forward progress should be still guaranteed because > * pages on the pcp list can only belong to MOVABLE_ZONE > * because has_unmovable_pages explicitly checks for > * PageBuddy on freed pages on other zones. > > + */ > > + if (ret) > > + drain_all_pages(zone); > > } while (ret); > > > > /* Ok, all of our target is isolated. > > -- > > 2.25.1 > > > > -- > Michal Hocko > SUSE Labs