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]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id B1BFACAC5A5 for ; Wed, 24 Sep 2025 17:40:53 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 1AA638E0012; Wed, 24 Sep 2025 13:40:53 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 182888E0001; Wed, 24 Sep 2025 13:40:53 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 0BED38E0012; Wed, 24 Sep 2025 13:40:53 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id EE8988E0001 for ; Wed, 24 Sep 2025 13:40:52 -0400 (EDT) Received: from smtpin18.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay03.hostedemail.com (Postfix) with ESMTP id B8A53BC1B4 for ; Wed, 24 Sep 2025 17:40:52 +0000 (UTC) X-FDA: 83924859144.18.28B78CE Received: from fanzine2.igalia.com (fanzine2.igalia.com [213.97.179.56]) by imf11.hostedemail.com (Postfix) with ESMTP id 1F6364000A for ; Wed, 24 Sep 2025 17:40:50 +0000 (UTC) Authentication-Results: imf11.hostedemail.com; dkim=pass header.d=igalia.com header.s=20170329 header.b=poMllSFx; dmarc=pass (policy=none) header.from=igalia.com; spf=pass (imf11.hostedemail.com: domain of mfo@igalia.com designates 213.97.179.56 as permitted sender) smtp.mailfrom=mfo@igalia.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1758735651; a=rsa-sha256; cv=none; b=CwahBP42xJLV7akO4g/mIWpjZaUACWLrPy/ZGhKSRz/eB+zcf23WVSRTN99X/KWIEsmbQZ JJxtyM9PBCg31hj0kSPhe3yxs5EyHtTq0X8wK6XN2YzXRhOCo5Kp0AORAIUhsJ1CIa6Yrt bHvCjjHeMWMTG3kBr9oQUekkkAGhFQU= ARC-Authentication-Results: i=1; imf11.hostedemail.com; dkim=pass header.d=igalia.com header.s=20170329 header.b=poMllSFx; dmarc=pass (policy=none) header.from=igalia.com; spf=pass (imf11.hostedemail.com: domain of mfo@igalia.com designates 213.97.179.56 as permitted sender) smtp.mailfrom=mfo@igalia.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1758735651; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=WORvJmTYWvO70O+J4Bbi/mV+ttGZbGHrOxbkkudcayo=; b=qNkyqu4pK6KOJb25fhRrSXEbN2apxenJMPW2hfo6MoyNuo9vK2TYDOj5Z0PWY9j5TsohGt rDK399Thbe4dWx41ixYigqUk6Kjwh0XlnE5ZU0SdJvsoo0oO/qAk1Cq3+KFVm/v3fRigqy ZB2A51RSbZDRwSvmYEGPz34wMunIpBA= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=igalia.com; s=20170329; h=Content-Transfer-Encoding:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:Cc:To:From:Sender:Reply-To:Content-Type:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=WORvJmTYWvO70O+J4Bbi/mV+ttGZbGHrOxbkkudcayo=; b=poMllSFxyWwaxbRMnhIhvy/7gG Vv3kHUhfitXWX5+DCa587KuKpCGAEpvpIp0CidIGTkAPcc9ItXF0YLCIpn8/x4Bhv4m5aLfUdUFRv wcJT0kUPPM44BFEAVH18kJo3yMQMybzx0FpN7ETzRq5H/+p9V68me1CkULYvLi/zoUjsHfH9uVTUh Y/qu33VahXawv0QuQ6O4a5WSyOLCjckL/B0+MpF5u7oV1gFX8ZlgofNnDiGgzCZ1aj3HOp5+7XFhI KbZVf8SFjgdOSSkrN9mtcgSqCUD1DKlSotbEd6ohIRtHoWxq7gMy87EPIhxJ2SN+zqGlHsBTwCHUz Iyr2YFmg==; Received: from [179.159.118.139] (helo=localhost.localdomain) by fanzine2.igalia.com with esmtpsa (Cipher TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim) id 1v1TTx-00Gz9Z-Dh; Wed, 24 Sep 2025 19:40:46 +0200 From: Mauricio Faria de Oliveira To: Andrew Morton , Vlastimil Babka Cc: Oscar Salvador , Suren Baghdasaryan , Michal Hocko , Brendan Jackman , Johannes Weiner , Zi Yan , linux-mm@kvack.org, linux-kernel@vger.kernel.org, kernel-dev@igalia.com Subject: [PATCH 3/3] mm/page_owner: update Documentation with 'print_handle' and 'print_stack' Date: Wed, 24 Sep 2025 14:40:23 -0300 Message-ID: <20250924174023.261125-4-mfo@igalia.com> X-Mailer: git-send-email 2.48.1 In-Reply-To: <20250924174023.261125-1-mfo@igalia.com> References: <20250924174023.261125-1-mfo@igalia.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: 1F6364000A X-Stat-Signature: 1zwxyuk8mpyge3jqxsbfjuq3rpg9oud3 X-Rspam-User: X-HE-Tag: 1758735650-229084 X-HE-Meta: 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 9VuvS49d MRmhNoDv7v6wumQRM8l+l68DsZ5+2rhGtlIS2X9KDfmZz4VOelZocDSOgaGGok4OD5WQOsDXmnf6wrQTPeygSRRDMF0NZgdA0ehQnsUGXaa+QCWqVwVEJuXa8y1J2wuX8hgRlS7pDfsvPrGYmJfn5iCVbFBviJ/ASjNDdywKkUdbHBvBKiwRwy5Bb9JncMhiliwLugnfATuWpaeI2e7X1Uo1Cs8+d+GTmaPIzooggMGpdzz0gEQ72lh1xzaJf/skLbZOuz8EwPDdMG7DX1OKGlzB/mUhXpt64besflqi63StYNw/GhF/xROMFpw5Nt9yPo+vb 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: List-Subscribe: List-Unsubscribe: Describe and provide examples for 'print_handle' and 'print_stack'. Signed-off-by: Mauricio Faria de Oliveira --- Documentation/mm/page_owner.rst | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/Documentation/mm/page_owner.rst b/Documentation/mm/page_owner.rst index 3a45a20fc05a..fac14ff2e4a5 100644 --- a/Documentation/mm/page_owner.rst +++ b/Documentation/mm/page_owner.rst @@ -27,7 +27,10 @@ enabled. Other usages are more than welcome. It can also be used to show all the stacks and their current number of allocated base pages, which gives us a quick overview of where the memory is going without the need to screen through all the pages and match the -allocation and free operation. +allocation and free operation. It's also possible to show only a numeric +identifier of all the stacks (without stack traces) and their number of +allocated base pages (faster to read and parse, eg, for monitoring) that +can be matched with stacks later (options print_handle and print_stack). page owner is disabled by default. So, if you'd like to use it, you need to add "page_owner=on" to your boot cmdline. If the kernel is built @@ -95,6 +98,7 @@ Usage ... ... echo 7000 > /sys/kernel/debug/page_owner_stacks/count_threshold + echo 1 > /sys/kernel/debug/page_owner_stacks/print_handle cat /sys/kernel/debug/page_owner_stacks/show_stacks> stacks_7000.txt cat stacks_7000.txt post_alloc_hook+0x177/0x1a0 @@ -113,6 +117,15 @@ Usage __do_sys_finit_module+0x381/0x730 do_syscall_64+0x8d/0x150 entry_SYSCALL_64_after_hwframe+0x62/0x6a + handle: 42 + nr_base_pages: 20824 + ... + + echo 1 > /sys/kernel/debug/page_owner_stacks/print_handle + echo 0 > /sys/kernel/debug/page_owner_stacks/print_stack + cat /sys/kernel/debug/page_owner_stacks/show_stacks > handles_7000.txt + cat handles_7000.txt + handle: 42 nr_base_pages: 20824 ... -- 2.48.1