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=-0.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY autolearn=ham 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 3F0C2C31E46 for ; Wed, 12 Jun 2019 17:20:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 134852175B for ; Wed, 12 Jun 2019 17:20:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729544AbfFLRU1 (ORCPT ); Wed, 12 Jun 2019 13:20:27 -0400 Received: from out30-56.freemail.mail.aliyun.com ([115.124.30.56]:39276 "EHLO out30-56.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726004AbfFLRU0 (ORCPT ); Wed, 12 Jun 2019 13:20:26 -0400 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R361e4;CH=green;DM=||false|;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04420;MF=yang.shi@linux.alibaba.com;NM=1;PH=DS;RN=11;SR=0;TI=SMTPD_---0TU.Zjat_1560360018; Received: from US-143344MP.local(mailfrom:yang.shi@linux.alibaba.com fp:SMTPD_---0TU.Zjat_1560360018) by smtp.aliyun-inc.com(127.0.0.1); Thu, 13 Jun 2019 01:20:22 +0800 Subject: Re: [PATCH 4/4] mm: shrinker: make shrinker not depend on memcg kmem To: "Kirill A. Shutemov" Cc: ktkhai@virtuozzo.com, kirill.shutemov@linux.intel.com, hannes@cmpxchg.org, mhocko@suse.com, hughd@google.com, shakeelb@google.com, rientjes@google.com, akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <1559887659-23121-1-git-send-email-yang.shi@linux.alibaba.com> <1559887659-23121-5-git-send-email-yang.shi@linux.alibaba.com> <20190612025257.7fv55qmx6p45hz7o@box> <20190612101104.7rmjzmfy5owhqcif@box> From: Yang Shi Message-ID: Date: Wed, 12 Jun 2019 10:20:15 -0700 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.12; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 MIME-Version: 1.0 In-Reply-To: <20190612101104.7rmjzmfy5owhqcif@box> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 6/12/19 3:11 AM, Kirill A. Shutemov wrote: > On Tue, Jun 11, 2019 at 10:07:54PM -0700, Yang Shi wrote: >> >> On 6/11/19 7:52 PM, Kirill A. Shutemov wrote: >>> On Fri, Jun 07, 2019 at 02:07:39PM +0800, Yang Shi wrote: >>>> Currently shrinker is just allocated and can work when memcg kmem is >>>> enabled. But, THP deferred split shrinker is not slab shrinker, it >>>> doesn't make too much sense to have such shrinker depend on memcg kmem. >>>> It should be able to reclaim THP even though memcg kmem is disabled. >>>> >>>> Introduce a new shrinker flag, SHRINKER_NONSLAB, for non-slab shrinker, >>>> i.e. THP deferred split shrinker. When memcg kmem is disabled, just >>>> such shrinkers can be called in shrinking memcg slab. >>> Looks like it breaks bisectability. It has to be done before makeing >>> shrinker memcg-aware, hasn't it? >> No, it doesn't break bisectability. But, THP shrinker just can be called >> with kmem charge enabled without this patch. > So, if kmem is disabled, it will not be called, right? Then it is > regression in my opinion. This patch has to go in before 2/4. I don't think this is a regression. "regression" should mean something used to work, but it is broken now. Actually, deferred split shrinker never works with memcg. Anyway, either before 2/4 or after 2/4 looks ok. >