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=-3.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS 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 3C507C433DF for ; Mon, 25 May 2020 14:56:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1380120890 for ; Mon, 25 May 2020 14:56:55 +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="rgBxhahP" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404030AbgEYO4y (ORCPT ); Mon, 25 May 2020 10:56:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50726 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390921AbgEYO4x (ORCPT ); Mon, 25 May 2020 10:56:53 -0400 Received: from mail-lj1-x241.google.com (mail-lj1-x241.google.com [IPv6:2a00:1450:4864:20::241]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6574EC061A0E for ; Mon, 25 May 2020 07:56:53 -0700 (PDT) Received: by mail-lj1-x241.google.com with SMTP id k5so21022668lji.11 for ; Mon, 25 May 2020 07:56:53 -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; bh=Yz/iCNo6m0AB4cxN2lhc/SEr0qpr3e5JTbSbJHnwVIU=; b=rgBxhahPLGexiDdGfj/1yCvH/idNIEtEz+uUoV+m0qvlWDSbpeOv0ru+XBlrhVs3Mo paASWIqprgWhFyEyiDQUQkMZw63B8KqNumeTRqC9NyezMGqG6coxs6jlPY3Y0gurO3ef xZDm5kNwe0l7jtr/+webOXClGwgRFq8+RNKp48u2yBbEk8VXMGz7H/cCdPeVszeSoJLO Y+2uSPZ33CmHwjGoln7AYyW5J6OTubZDqkRNWDAHNFMrVCDzSxgBuAaKkjxzfOHF+5H3 LlVfWEhgFAXjsouBqP6CgrZaZhJr3sJPLFpWTihk/wdddYr3owUyq4WBTPnJwV7S+/yY wiNQ== 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; bh=Yz/iCNo6m0AB4cxN2lhc/SEr0qpr3e5JTbSbJHnwVIU=; b=Exc59fAlPJeE5XWaLJV4Egl5ztRgzaMBBwYxIIZAF/hH8Jq6fnFp3XUFJ0NRKxBkys 0RHt8DYC5ro1v+gs7N9mATFn1N4zK3yOUAsp2tfQoyy9PRYpqnc+fLDYVTSisg47zd+C XjLA5RMs/rNcNX0UJME+OLw62cXxLT3nwAP+D9Yl/xDt/bJYjUvI0+p25p5tqPB7IGGz nCOVd3vcOCYsr2z2zU03uSNwaJMRuuAkyanPQkQizH9vhYAg676L16wuOdQxivwFg+32 qeNgzeaHKK1kj3sP7o47CcZdDKIBOqVfA89aimbLcCVKCcs3aaastViEIrhZPBadjhRa oxhg== X-Gm-Message-State: AOAM533iZuVxBCtWhs+CXUwpo8eFPDcKJ9vgZkqJcNqPSoS3FjAuLrqf R4Cy77S/0r1AgC2V8tfjJGgAPQ== X-Google-Smtp-Source: ABdhPJx4ytdRNFb6NqA5DIjE3V32k85IYdmOTRCMb5IaUCzSBBAku30pQ6a6xJNGZNCFUIRc9k3qjg== X-Received: by 2002:a2e:8956:: with SMTP id b22mr15057648ljk.16.1590418611930; Mon, 25 May 2020 07:56:51 -0700 (PDT) Received: from box.localdomain ([86.57.175.117]) by smtp.gmail.com with ESMTPSA id v22sm643925ljj.75.2020.05.25.07.56.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 25 May 2020 07:56:51 -0700 (PDT) Received: by box.localdomain (Postfix, from userid 1000) id 56AC310230F; Mon, 25 May 2020 17:56:52 +0300 (+03) Date: Mon, 25 May 2020 17:56:52 +0300 From: "Kirill A. Shutemov" To: Konstantin Khlebnikov Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrew Morton , Vlastimil Babka , "Kirill A. Shutemov" Subject: Re: [PATCH] mm: dump_page: add debugfs file for dumping page state by pfn Message-ID: <20200525145652.u3xnom5fyuxvn7p4@box> References: <159041635119.987025.7321864888027213705.stgit@buzz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <159041635119.987025.7321864888027213705.stgit@buzz> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, May 25, 2020 at 05:19:11PM +0300, Konstantin Khlebnikov wrote: > Tool 'page-types' could list pages mapped by process or file cache pages, > but it shows only limited amount of state exported via procfs. > > Let's employ existing helper dump_page() to reach remaining information: > writing pfn into /sys/kernel/debug/dump_page dumps state into kernel log. > > # echo 0x37c43c > /sys/kernel/debug/dump_page > # dmesg | tail -6 > page:ffffcb0b0df10f00 refcount:1 mapcount:0 mapping:000000007755d3d9 index:0x30 > 0xffffffffae4239e0 name:"libGeoIP.so.1.6.9" > flags: 0x200000000020014(uptodate|lru|mappedtodisk) > raw: 0200000000020014 ffffcb0b187fd288 ffffcb0b189e6248 ffff9528a04afe10 > raw: 0000000000000030 0000000000000000 00000001ffffffff 0000000000000000 > page dumped because: debugfs request > > With CONFIG_PAGE_OWNER=y shows also stacks for last page alloc and free: > > page:ffffea0018fff480 refcount:1 mapcount:1 mapping:0000000000000000 index:0x7f9f28f62 > anon flags: 0x100000000080034(uptodate|lru|active|swapbacked) > raw: 0100000000080034 ffffea00184140c8 ffffea0018517d88 ffff8886076ba161 > raw: 00000007f9f28f62 0000000000000000 0000000100000000 ffff888bfc79f000 > page dumped because: debugfs request > page->mem_cgroup:ffff888bfc79f000 > page_owner tracks the page as allocated > page last allocated via order 0, migratetype Movable, gfp_mask 0x100dca(GFP_HIGHUSER_MOVABLE|__GFP_ZERO) > prep_new_page+0x139/0x1a0 > get_page_from_freelist+0xde9/0x14e0 > __alloc_pages_nodemask+0x18b/0x360 > alloc_pages_vma+0x7c/0x270 > __handle_mm_fault+0xd40/0x12b0 > handle_mm_fault+0xe7/0x1e0 > do_page_fault+0x2d5/0x610 > page_fault+0x2f/0x40 > page last free stack trace: > free_pcp_prepare+0x11e/0x1c0 > free_unref_page_list+0x71/0x180 > release_pages+0x31e/0x480 > tlb_flush_mmu+0x44/0x150 > tlb_finish_mmu+0x3d/0x70 > exit_mmap+0xdd/0x1a0 > mmput+0x70/0x140 > do_exit+0x33f/0xc40 > do_group_exit+0x3a/0xa0 > __x64_sys_exit_group+0x14/0x20 > do_syscall_64+0x48/0x130 > entry_SYSCALL_64_after_hwframe+0x44/0xa9 > > Signed-off-by: Konstantin Khlebnikov Looks useful to me: Acked-by: Kirill A. Shutemov -- Kirill A. Shutemov