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=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 7427FC433E0 for ; Wed, 3 Jun 2020 04:59:47 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 4E8C1206C3 for ; Wed, 3 Jun 2020 04:59:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4E8C1206C3 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id D2EE080007; Wed, 3 Jun 2020 00:59:45 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id CB6798E0006; Wed, 3 Jun 2020 00:59:45 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id BA5BC80007; Wed, 3 Jun 2020 00:59:45 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0004.hostedemail.com [216.40.44.4]) by kanga.kvack.org (Postfix) with ESMTP id 9CDCC8E0006 for ; Wed, 3 Jun 2020 00:59:45 -0400 (EDT) Received: from smtpin02.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 4C73F181AEF15 for ; Wed, 3 Jun 2020 04:59:45 +0000 (UTC) X-FDA: 76886697930.02.spark84_37fe98b9d0316 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin02.hostedemail.com (Postfix) with ESMTP id 25078127C for ; Wed, 3 Jun 2020 04:59:45 +0000 (UTC) X-HE-Tag: spark84_37fe98b9d0316 X-Filterd-Recvd-Size: 2995 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf02.hostedemail.com (Postfix) with ESMTP for ; Wed, 3 Jun 2020 04:59:44 +0000 (UTC) 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 DB27155D; Tue, 2 Jun 2020 21:59:43 -0700 (PDT) Received: from [10.163.77.218] (unknown [10.163.77.218]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 1BC6C3F6CF; Tue, 2 Jun 2020 21:59:40 -0700 (PDT) Subject: Re: [PATCH] mm/vmstat: Add events for PMD based THP migration without split To: Matthew Wilcox Cc: linux-mm@kvack.org, hughd@google.com, Naoya Horiguchi , Zi Yan , John Hubbard , Andrew Morton , linux-kernel@vger.kernel.org References: <1590118444-21601-1-git-send-email-anshuman.khandual@arm.com> <20200602150141.GN19604@bombadil.infradead.org> <2d4634ce-9167-6ca6-fb91-f3c671fff672@arm.com> <20200603025729.GO19604@bombadil.infradead.org> From: Anshuman Khandual Message-ID: <280304c7-882b-cb2f-55bf-87b2e2f28711@arm.com> Date: Wed, 3 Jun 2020 10:28:41 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20200603025729.GO19604@bombadil.infradead.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 25078127C X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam02 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 06/03/2020 08:27 AM, Matthew Wilcox wrote: > On Wed, Jun 03, 2020 at 06:56:57AM +0530, Anshuman Khandual wrote: >> On 06/02/2020 08:31 PM, Matthew Wilcox wrote: >>> On Fri, May 22, 2020 at 09:04:04AM +0530, Anshuman Khandual wrote: >>>> This adds the following two new VM events which will help in validating PMD >>>> based THP migration without split. Statistics reported through these events >>>> will help in performance debugging. >>>> >>>> 1. THP_PMD_MIGRATION_SUCCESS >>>> 2. THP_PMD_MIGRATION_FAILURE >>> >>> There's nothing actually PMD specific about these events, is there? >>> If we have a THP of a non-PMD size, you'd want that reported through the >>> same statistic, wouldn't you? >> >> Yes, there is nothing PMD specific here and we would use the same statistics >> for non-PMD size THP migration (if any) as well. But is THP migration really >> supported for non-PMD sizes ? CONFIG_ARCH_ENABLE_THP_MIGRATION depends upon >> CONFIG_TRANSPARENT_HUGEPAGE without being specific or denying about possible >> PUD level support. Fair enough, will drop the PMD from the events and their >> functions. > > I guess you haven't read my large pages patchset? I believe you are referring this "[PATCH v5 00/39] Large pages in the page cache" (https://lkml.org/lkml/2020/5/28/1755). Unfortunately, I have not been following the series. But is there something else in particular that needs to be taken care of as well ?