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=-2.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 6B2A7C3A5A3 for ; Thu, 22 Aug 2019 15:49:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 39CB023400 for ; Thu, 22 Aug 2019 15:49:19 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=shutemov-name.20150623.gappssmtp.com header.i=@shutemov-name.20150623.gappssmtp.com header.b="L8WPD7dT" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389596AbfHVPtR (ORCPT ); Thu, 22 Aug 2019 11:49:17 -0400 Received: from mail-ed1-f68.google.com ([209.85.208.68]:38560 "EHLO mail-ed1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726387AbfHVPtR (ORCPT ); Thu, 22 Aug 2019 11:49:17 -0400 Received: by mail-ed1-f68.google.com with SMTP id r12so8610882edo.5 for ; Thu, 22 Aug 2019 08:49:16 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=shutemov-name.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=DJ/eC3LGuOL6//+DGNThc9YJfZBuiT1PO54o1KGcu30=; b=L8WPD7dTrU3n/Wq91GZgxnLyJoEfJzls7dAI7jRFPS2OQUmzaI3fJOHoWKcsrFZaVP RvSdHC7FZ1z0sOk8IdvvB29K2NqNten9KEG0gvLCmSqtQFfFJ5uMgD4v43b36IcAv9bX KTtYiU4ADpMXlaL5IafhA5DT+coI1u60NzoVzh5Rw8mz0K07RDv2bxZ/AeulQBVIFehw kEYLsFZGGD1vqAftG2zGF3XUbDDqHOCP29WxaNddvB8HHtjCJm1SU7vcdk5mJlPG0h9V x9uHHr9bupiR3K6DrnD2mLXjtMpcO3ASDogaK2ABY0czTEVx4Z8FVuvhwL6Xr5eg/0q4 gRHw== 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:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=DJ/eC3LGuOL6//+DGNThc9YJfZBuiT1PO54o1KGcu30=; b=ZU5PMRhGYBoyBYIVZvUWgNMM9Uh6dPxtYEtmb9K5EmdJQ6mKDkzFd7riayFsNt1fu/ YQ9UcWK3ktuavCcCI7ypf6Ck+up4ldIh7grAKddN2JMP16bVPQG5jEkME7GLlzsCjuvZ 808cYwTHqXzcsTzO7XEaEj/c9a2wVMy56NCaCXTATtO8PFtKlnk+kgnYWwnPgUSXukod 2NIgSG2zCKZ7yyOjuecLzMjqR3UBk4217fj946xymq26AT3SmETKI7pQIHZd8CYH6arS FIJRNdtRQk2EhmNKvcw1FETpmtYM/1+L6kLI6Ry0py2IgE8UkbFrZn1+q01UoACXLtlV DphA== X-Gm-Message-State: APjAAAU5ly7Llqh9OlQPS+VEEB0cItYrxdvVVfo7Xs1CNY6r9lOGzCrV ZjAj+TEWvFRBbq+4UkEvZFsh2g== X-Google-Smtp-Source: APXvYqzD5H/EuYEoQQqsHvjG6zA2nUnP7NlXkdSM5hi9Tt50tWsVXfctor7rYt6YdvlbkGgeWIoYpQ== X-Received: by 2002:a05:6402:50a:: with SMTP id m10mr21388362edv.173.1566488955883; Thu, 22 Aug 2019 08:49:15 -0700 (PDT) Received: from box.localdomain ([86.57.175.117]) by smtp.gmail.com with ESMTPSA id p20sm3710384eja.59.2019.08.22.08.49.15 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 22 Aug 2019 08:49:15 -0700 (PDT) Received: by box.localdomain (Postfix, from userid 1000) id 7225D100853; Thu, 22 Aug 2019 18:49:14 +0300 (+03) Date: Thu, 22 Aug 2019 18:49:14 +0300 From: "Kirill A. Shutemov" To: Vlastimil Babka Cc: Michal Hocko , kirill.shutemov@linux.intel.com, Yang Shi , hannes@cmpxchg.org, rientjes@google.com, akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [v2 PATCH -mm] mm: account deferred split THPs into MemAvailable Message-ID: <20190822154914.gb5clks2tzziobfx@box> References: <1566410125-66011-1-git-send-email-yang.shi@linux.alibaba.com> <20190822080434.GF12785@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: NeoMutt/20180716 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Aug 22, 2019 at 02:56:56PM +0200, Vlastimil Babka wrote: > >> @@ -2816,11 +2821,14 @@ void free_transhuge_page(struct page *page) > >> ds_queue->split_queue_len--; > >> list_del(page_deferred_list(page)); > >> } > >> + __mod_node_page_state(page_pgdat(page), NR_KERNEL_MISC_RECLAIMABLE, > >> + -page[2].nr_freeable); > >> + page[2].nr_freeable = 0; > > Wouldn't it be safer to fully tie the nr_freeable use to adding the page to the > deffered list? So here the code would be in the if (!list_empty()) { } part above. > > >> spin_unlock_irqrestore(&ds_queue->split_queue_lock, flags); > >> free_compound_page(page); > >> } > >> > >> -void deferred_split_huge_page(struct page *page) > >> +void deferred_split_huge_page(struct page *page, unsigned int nr) > >> { > >> struct deferred_split *ds_queue = get_deferred_split_queue(page); > >> #ifdef CONFIG_MEMCG > >> @@ -2844,6 +2852,9 @@ void deferred_split_huge_page(struct page *page) > >> return; > >> > >> spin_lock_irqsave(&ds_queue->split_queue_lock, flags); > >> + page[2].nr_freeable += nr; > >> + __mod_node_page_state(page_pgdat(page), NR_KERNEL_MISC_RECLAIMABLE, > >> + nr); > > Same here, only do this when adding to the list, below? Or we might perhaps > account base pages multiple times? No, it cannot be under list_empty() check. Consider the case when a THP got unmapped 4k a time. You need to put it on the list once, but account it every time. -- Kirill A. Shutemov