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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 091E3C433EF for ; Tue, 11 Jan 2022 05:01:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232195AbiAKFBa (ORCPT ); Tue, 11 Jan 2022 00:01:30 -0500 Received: from foss.arm.com ([217.140.110.172]:41870 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229436AbiAKFBX (ORCPT ); Tue, 11 Jan 2022 00:01:23 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id D173D1FB; Mon, 10 Jan 2022 21:01:19 -0800 (PST) Received: from [10.163.72.245] (unknown [10.163.72.245]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id EDB923F774; Mon, 10 Jan 2022 21:01:16 -0800 (PST) Subject: Re: [PATCH] mm/migration: Add trace events for THP migrations To: Naoya Horiguchi Cc: linux-mm@kvack.org, Steven Rostedt , Ingo Molnar , Andrew Morton , Zi Yan , Naoya Horiguchi , John Hubbard , Matthew Wilcox , linux-kernel@vger.kernel.org References: <1641531575-28524-1-git-send-email-anshuman.khandual@arm.com> <20220111015822.GA799985@u2004> From: Anshuman Khandual Message-ID: Date: Tue, 11 Jan 2022 10:31:21 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20220111015822.GA799985@u2004> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 1/11/22 7:28 AM, Naoya Horiguchi wrote: > Hi Anshuman, > > On Fri, Jan 07, 2022 at 10:29:35AM +0530, Anshuman Khandual wrote: >> This adds two trace events for PMD based THP migration without split. These >> events closely follow the implementation details like setting and removing >> of PMD migration entries, which are essential operations for THP migration. > > I often want to check which individual pages are migrated to which places > (or not migrated) for testing, so these new tracepoints could help me. > Maybe these can be much greater if they can handle other types of page > migration for raw pages and hugetlb pages. Is it hard to cover all such > page migration events? Are you suggesting to cover all migration entry transitions for normal and HugeTLB pages as well ? migrate_pages() unmap_and_move_huge_page() try_to_migrate() make_writable_migration_entry() <--- make_readable_migration_entry() <--- remove_migration_ptes() <--- unmap_and_move() __unmap_and_move() try_to_migrate() make_writable_migration_entry() <--- make_readable_migration_entry() <--- remove_migration_ptes() <--- > > Thanks, > Naoya Horiguchi >