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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8D50FC433EF for ; Wed, 13 Apr 2022 15:13:47 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id A870C6B0073; Wed, 13 Apr 2022 11:13:46 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id A360D6B0074; Wed, 13 Apr 2022 11:13:46 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8B1C66B0075; Wed, 13 Apr 2022 11:13:46 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (relay.hostedemail.com [64.99.140.25]) by kanga.kvack.org (Postfix) with ESMTP id 7D7866B0073 for ; Wed, 13 Apr 2022 11:13:46 -0400 (EDT) Received: from smtpin16.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 536DA616E4 for ; Wed, 13 Apr 2022 15:13:46 +0000 (UTC) X-FDA: 79352200452.16.A003907 Received: from mail-lf1-f50.google.com (mail-lf1-f50.google.com [209.85.167.50]) by imf06.hostedemail.com (Postfix) with ESMTP id CC41118000C for ; Wed, 13 Apr 2022 15:13:45 +0000 (UTC) Received: by mail-lf1-f50.google.com with SMTP id b21so4141072lfb.5 for ; Wed, 13 Apr 2022 08:13:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=shutemov-name.20210112.gappssmtp.com; s=20210112; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=RAAc5fa4F90WsSmMhyXG1BxDYmJJkdC+jeev0xBh19I=; b=xX5d3iFAgBwcsG6s5J2C4/fLi6LlyCP196z7KBeTpn4ttNrT/0VeBmqpZrVANXjtIM c+eUxPnL6kXEYJbv4Wu711Aji9cUBck5mBk5FPqthYuLmchh9cr8gy0oZMXvZNReQYj1 BmLMVOWE8WynJFd75yYTUjAO/Z5R88LGTxqx1qVZW03UaLpsXNPqkOogT9Y2TBkZffCD kTujj7PajUDP5BlNSVjQYaWeEt4OYUyRNCaRGxL2QE+H9R4IxgqWYQ+E1oV5KFlds+wv /9WiANG5JdMNnpyoOWRq/uIjvdTdz6N+UOz8yvngBhyX3YddzCFyhpeCtSDAgX0tVIoE Upcg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=RAAc5fa4F90WsSmMhyXG1BxDYmJJkdC+jeev0xBh19I=; b=X6KN23Yiqg0BNq2IMYqkHNzRiGnMUhqNq+PxNju/LE9LPbsA5dxra76FXidVCoRU6J z8hdjEOHMT6GBQe5wIryF5Bk0KMahR36T8ojwOhsQYdMyT7j8Bqt+PHUrKe7+bcGxiBc zXOgZK5yXzvLT6/MtphWRwzuFd7Yc/YtrgqrhWAfkLflcPpWUIgguzBua88a9uuz/p0+ iYwRu78WkS8+lq3oVtP0E4Jm9mG/RYp3ys3kCnBEWTAXCQsodtF5qB6dPoVZ3gT8JV37 WEJwMoAPisuwgENArhFsnHJuoRvbux091xHu/oJstH8+LVlxMOvPqX96jkAWJXYDRHfp +XZw== X-Gm-Message-State: AOAM531+oRmCiLXh24zw3ltvAX7pJvPNNnlPKTlQjbjncy2aTj77MU6i LW98cpznz0e9+V6yFvRTa64UlQ== X-Google-Smtp-Source: ABdhPJzGMpUSiE9GVIjXl9oR+9/sm+CrqfOI2L7c3sX8hQf2neNKEahVQsBzUzo5C7G8Z/yzmwf7dQ== X-Received: by 2002:a19:da12:0:b0:46b:926f:d34b with SMTP id r18-20020a19da12000000b0046b926fd34bmr15227644lfg.646.1649862824074; Wed, 13 Apr 2022 08:13:44 -0700 (PDT) Received: from box.localdomain ([86.57.175.117]) by smtp.gmail.com with ESMTPSA id bj8-20020a2eaa88000000b0024b6abfc2ddsm741396ljb.114.2022.04.13.08.13.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 13 Apr 2022 08:13:43 -0700 (PDT) Received: by box.localdomain (Postfix, from userid 1000) id 0929910369B; Wed, 13 Apr 2022 18:15:17 +0300 (+03) Date: Wed, 13 Apr 2022 18:15:17 +0300 From: "Kirill A. Shutemov" To: Mike Rapoport Cc: Dave Hansen , "Kirill A. Shutemov" , Borislav Petkov , Andy Lutomirski , Sean Christopherson , Andrew Morton , Joerg Roedel , Ard Biesheuvel , Andi Kleen , Kuppuswamy Sathyanarayanan , David Rientjes , Vlastimil Babka , Tom Lendacky , Thomas Gleixner , Peter Zijlstra , Paolo Bonzini , Ingo Molnar , Varad Gautam , Dario Faggioli , Brijesh Singh , David Hildenbrand , x86@kernel.org, linux-mm@kvack.org, linux-coco@lists.linux.dev, linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org, Mike Rapoport Subject: Re: [PATCHv4 1/8] mm: Add support for unaccepted memory Message-ID: <20220413151517.tzd76kzja3424lqu@box.shutemov.name> References: <20220405234343.74045-1-kirill.shutemov@linux.intel.com> <20220405234343.74045-2-kirill.shutemov@linux.intel.com> <767c2100-c171-1fd3-6a92-0af2e4bf3067@intel.com> <20220409155423.iv2arckmvavvpegt@box.shutemov.name> <6c976344-fdd6-95cd-2cb0-b0e817bf0392@intel.com> <20220413114001.wdsi2xrm4btrghms@box.shutemov.name> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Server: rspam09 X-Rspam-User: X-Stat-Signature: tmdqyjdcinf6h37gje7dooxp1ydh9oad Authentication-Results: imf06.hostedemail.com; dkim=pass header.d=shutemov-name.20210112.gappssmtp.com header.s=20210112 header.b=xX5d3iFA; dmarc=none; spf=none (imf06.hostedemail.com: domain of kirill@shutemov.name has no SPF policy when checking 209.85.167.50) smtp.mailfrom=kirill@shutemov.name X-Rspamd-Queue-Id: CC41118000C X-HE-Tag: 1649862825-790034 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: On Wed, Apr 13, 2022 at 05:48:09PM +0300, Mike Rapoport wrote: > On Wed, Apr 13, 2022 at 02:40:01PM +0300, Kirill A. Shutemov wrote: > > On Mon, Apr 11, 2022 at 01:07:29PM +0300, Mike Rapoport wrote: > > > On Sun, Apr 10, 2022 at 11:38:08PM -0700, Dave Hansen wrote: > > > > On 4/9/22 08:54, Kirill A. Shutemov wrote: > > > > > On Fri, Apr 08, 2022 at 11:55:43AM -0700, Dave Hansen wrote: > > > > > > > > >>> if (fpi_flags & FPI_TO_TAIL) > > > > >>> to_tail = true; > > > > >>> else if (is_shuffle_order(order)) > > > > >>> @@ -1149,7 +1192,8 @@ static inline void __free_one_page(struct page *page, > > > > >>> static inline bool page_expected_state(struct page *page, > > > > >>> unsigned long check_flags) > > > > >>> { > > > > >>> - if (unlikely(atomic_read(&page->_mapcount) != -1)) > > > > >>> + if (unlikely(atomic_read(&page->_mapcount) != -1) && > > > > >>> + !PageUnaccepted(page)) > > > > >>> return false; > > > > >> > > > > >> That probably deserves a comment, and maybe its own if() statement. > > > > > > > > > > Own if does not work. PageUnaccepted() is encoded in _mapcount. > > > > > > > > > > What about this: > > > > > > > > > > /* > > > > > * page->_mapcount is expected to be -1. > > > > > * > > > > > * There is an exception for PageUnaccepted(). The page type can be set > > > > > * for pages on free list. Page types are encoded in _mapcount. > > > > > * > > > > > * PageUnaccepted() will get cleared in post_alloc_hook(). > > > > > */ > > > > > if (unlikely((atomic_read(&page->_mapcount) | PG_unaccepted) != -1)) > > > > > > Maybe I'm missing something, but isn't this true for any PageType? > > > > PG_buddy gets clear on remove from the free list, before the chec. > > > > PG_offline and PG_table pages are never on free lists. > > Right, this will work 'cause PageType is inverted. I still think this > condition is hard to parse and I liked the old variant with > !PageUnaccepted() better. Well the old way to deal with PageUnaccepted() had a flaw: if the page is PageUnaccepted() it will allow any other page types to pass here. Like PG_unaccepted + PG_buddy will slide here. > Maybe if we wrap the whole construct in a helper it will be less eye > hurting. Hm. Any suggestion how such helper could look like? Cannot think of anything sane. -- Kirill A. Shutemov